Check engine light cause repaired, but won’t stay off

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98_Q45
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…And this is also a precaution that, sometimes you have to be mindful who you take such cars to for complex electrical issues. Too many places charge for stuff and fix nothing. And with many techs these days upping their service prices, I can’t afford to pay for repairs that aren’t done right. They want $100+tax just to remove a couple bolts sometimes.

In my case, my rear 02 sensor wires were mixed with aftermarket sensor when I brought it. Idk why the previous owners attempted this or why it was needed. Probably a desperate attempt to fix a check engine light to pass California quality smog test (won’t pass if check engine light is on). Regardless, light stayed on, code never went away for years. I paid to replace both sensors with new aftermarket. $250 later, nothing.

However, my bad fuel mileage has been becoming a financial issue. Especially at the $3+ a gallon it’s been AND using premium.

Anyhow, I was getting all kind of weird codes for rear oxygen sensor, and either a flat 0 on one side and a flat 1.28 or something. No movement at all. Front o2 were okay and also replaced with original harness so no issue there.

Previous shop wanted to replace o2 sensor again, but I decided to do a little research myself: both rear sensors had mixed up wiring. I even replaced one at a time, that was showing the Fault. It started responding, but then was saying the other bank was at 0. So next day I re-wired the other one, using the service manual here for color codes along with Bosch color codes for wires.

Now both rear sensors are functioning and fluctuating as they should on the data chart (and I’m not very versed in interpreting data but, I have the little Bluetooth thing on my phone that I can plug in to the OBD and read). The issue with my car bogging and gas usage I’ve not yet confirmed solved only driving 5 miles around town but, so far it’s not occurring. I’ll have to drive it longer to ensure.

So yeah, that’s a big step so far. Now on to the airbag light, which I might have to go to the dealer for a proper read lol. I have a different GM car, and the airbag light came on the other day. Luckily it self diagnoses so I just found a connection under the seat must have gotten disturbed when I was detailing the other day. Now the light is off.

Moral of story: sometimes it takes some hardcore service manual reading to get rid of these codes. Even if you don’t understand the technicalities of it, just getting the fundamental answers is all you need (I didn’t do any testing or poking wires, just looked at the color diagram and matched it to Bosch oxygen sensor color diagram which is VERY different). Screw pre-cut aftermarket oxygen sensors. Far too easy to get mixed up.
Last edited by Rogue One on Fri May 03, 2024 6:37 am, edited 1 time in total.
Reason: Revise Title


98_Q45
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Update; might have spoke too soon:

Light stayed off after a few on/off starts. However seems like the same codes for knock sensor and heater oxygen sensor have come back, however at least the oxygen sensors are responding. So far they flat 0.14 when idle, but move as I’m driving. Before, they were both flat lines doing absolutely nothing (mind you I’m talking only rear o2).

I’m almost wondering if a bad o2 connection could trip the knock sensor, as engine bogging is still there. Aye.

I’m going to check drivers side connections again since I did that before I fully figured out the wiring diagram colors.

I brought a o2 harness 4 wire from Amazon, it didn’t fit the OE type sensor and the colors were different. I’ll need to double check that I matched them up correctly, but I only did one side with that. But that was the only thing I could find closest to a connector.

Will re-update with findings.

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VStar650CL
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The ECM monitors current through the O2 heater elements to determine if they're working. Because they're generally controlled from the low side, it's possible for miswiring to create a short circuit from power and blow the ECM output. For the same reason, it's impossible for the ECM to diagnose whether a no-current situation is from an open sensor, open wire, shorted wire, blown fuse, or blown output. It only knows there's no current flowing.

Check voltage on the heater wires with the engine at warm idle, you should see battery voltage on the plus wire and half a volt or less on the minus wire. If the plus wire reads zero then either the fuse is blown or the power wire is open. If the minus wire reads near battery voltage, either the signal wire is open or the ECM output is blown open. If that all checks good, raise the RPM's to about 4K, you should see the minus wire go to near battery voltage. If it remains near 0V then either the signal wire is shorted to ground or the ECM output is blown short.

98_Q45
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Thanks,

I’m going to recheck the wires again just to be sure. I might have gotten it mixed up with the new harness that didn’t really match. I just had a hard time initially reading what the colors on the harness were supposed to be for. But I’ll check the fuse again too

But like I said before, previous mechanic worked on it seemed to be taking a wild guess and only thing that was right was one heater wire.

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VStar650CL
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98_Q45 wrote:
Wed May 01, 2024 9:47 pm
But like I said before, previous mechanic worked on it seemed to be taking a wild guess and only thing that was right was one heater wire.
That's why I'm a little worried about your ECM. The heater drivers are just big transistors, and it is possible for a "wild guess" to blow them up. I'll cross my fingers for you.

98_Q45
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Well I went back thru and rechecked the wires, they were good but I ended up cutting the tape and kinda re-doing the connectors a bit. But overall: this is what I’m getting on the scanner. The bogging issue I’m starting to now wonder if it may be due to something with the evap system. Seems turning on/off the engine or opening cap for refueling either triggers or makes it go away.

But so far, the CEL has stayed off for the day after a few on/off and driving 60 miles. But once that bogging issue occurs, usually it triggers knock sensor code. This time nothing:

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VStar650CL
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If taking the cap off helps, then you might have a flooded canister or stuck vent valve which is preventing the purge system from working properly. Try pinching off the purge line at the manifold, loosen the cap, and take it for a drive. If that helps, then there's a blockage someplace in the vent path.

98_Q45
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That’s what I’m starting to wonder, however I did do the cleaning awhile back of the line of the charcoal canister from under the muffler (California emissions) to the engine. I aired out a lot of charcoal stuff and changed the canister, not sure I recall changing the vent on it. The one in the engine there’s a couple, but it’s not telling me which one it could be.

Also if it makes any difference, engine starts rapidly for a couple hours, after being run at operating temperature. Last time I had a similar issue, it would start in one click when cold, but then crank Extended when hot. When you say pinch off the line, which do you refer? The main coming from the canister, adjacent vent valve?

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VStar650CL
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Depends if your car is Cali or Fed. For Cali, it looks easiest to pinch off the big line from the tank to the Purge Volume Valve. For Fed, find the line connecting the canister to both the Purge/EGR Solenoid and the EGRC-BPT and pinch it off at the canister. With the cap loose and the main purge pinched off, basically all the evap plumbing is excluded. In both cases, if that makes her run better then you know it's an evap problem.

By the way, if it's a Cali car and you had a busted charcoal bag, did you change out the Purge Volume Control Valve? They usually get clogged solid with crap and blowing them clean doesn't usually work. They're stepper-driven and charcoal always gets trapped behind the plunger. The FSM shows the Fed models not having one, so no worries if that's the case.

98_Q45
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Well I checked out and cleaned the purge valves under engine, not getting codes for any and they didn’t have any traces of carbon or sounds. So probably not going to fuss with it much more than that.

From more research I’ve done, it seems to be I’m running lean and since my oxygen sensors are fluctuating after the converter, it might actually be bad cats after all. Is anyone here willing to see what their post cats are doing in comparison to mine? Looks like I’m below 0.4 volts.

Regardless, this sucks. I’m maxing out on possibilities and it’s just becoming too time consuming to keep chasing this issue. At this point if I get this fixed, I’m basically driving a new car lol, but issue still seems to come and go…however it’s been most persistent over the past 6 months to where it’s hardly fun to drive anymore, and gas mileage sucks.

I feel like one of those Craigslist sellers who be like: “it has a problem but idk what it is and don’t want to put anymore money into it” lol. But at least I’m checking off boxes for stuff that should have been replaced anyway. Fixing any “rigged” components and letting the computer read properly. Mind you, this is after driving off the highway and engine moving. At idle it is the flat

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And here’s just idle with occasional fluctuation:

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Guess my oil smoking maybe ruined my cats. Will try another cat cleaner, but I’m getting no codes for cat efficiency hmm…

Also the oxygen sensor heater code is back to stay. I know I wired it right but maybe the incorrect wiring messed up the sensors’s heaters. Idk.

98_Q45
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Well just another update, issue didn’t seem to get resolved as I thought. Took for spin today, and with temps near 90 and testing in mild stop and go traffic (nothing too major but just driving down a long stretch of boulevard with multiple stop lights), engine got really hot today while steady bogging, almost went past the line that gets into the H section. And that’s with the a/c off. If I was running the a/c it probably would have boiled over.

I’m starting to be convinced it’s the torque converter or catalytic converter. Either one. But the only code that stays persistent is the knock sensor, but I just can’t imagine knock sensor would be causing that much of an issue. I think the engine feels the dragging and knock sensor triggers. I’m almost flooring it just to pull off from a stop light, then the RPMs slowly go to 3,000 before it’ll shift back down. And doing that every half mile or so, really seems to run the engine hot and suck up s*** load of gas.

I just need to find some place that can properly diagnose it. Seems relying on codes to figure this out just isn’t working. What sucks worse is the issue randomly comes and goes…but lately it’s been persistent almost every time I drive, which means the malfunction has to be progressing. But with the age/mileage, the suggested solution seems to be new vehicle versus figuring it out. Other than this, it rides and starts beautifully.

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VStar650CL
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If you think it's the cats, you can do one of two things. If you can get at them, pop out the front O2's and see if the power comes back. It will be loud of course, but if it has good power, that's a smoking gun for an exhaust blockage. The other way is to buy a cheap vacuum gauge. Manifold vacuum should read 18~20" Hg at idle, and it should drop momentarily and then recover when you raise and hold the RPM's. If instead it gradually drops way off, that's a smoking gun for a blockage. Either way, at least you'll know for certain whether the cats are causing your issue.

98_Q45
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VStar650CL wrote:
Mon May 20, 2024 5:49 am
If you think it's the cats, you can do one of two things. If you can get at them, pop out the front O2's and see if the power comes back. It will be loud of course, but if it has good power, that's a smoking gun for an exhaust blockage. The other way is to buy a cheap vacuum gauge. Manifold vacuum should read 18~20" Hg at idle, and it should drop momentarily and then recover when you raise and hold the RPM's. If instead it gradually drops way off, that's a smoking gun for a blockage. Either way, at least you'll know for certain whether the cats are causing your issue.

I can get to the rear cat02 but, the pre cat02 are hard to reach. I had those done by a shop last year or so.

But I’m still leaning towards something with transmission and made an appointment this week. I can’t imagine it’s exhaust related simply because the engine has no issue with idle or starting. It’s just once the drive is engaged and hits operating temperature, it drags and the engine fan is whirring but the car barely wants to move.

But the catalytic probably is dead anyway, I just don’t think it’s the cause of the issue. Thought I could be wrong. Rather be wrong because a catalytic converter sounds easier than a torque converter lol. Plus I’m not getting any transmission codes at all. I’m just stumped.

There’s no big coolant loss or leaks either, just a little topping off every so often. At this point now I’m done trying to figure it out, I just need a shop to give me an accurate diagnostic. Torque converter not too expensive but I’m uncertain what the labor may be.

I need like $5,000 right now to get both my vehicles in tip top. I’m losing grip on the older car fight lol.

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VStar650CL
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Most cars with cloggo cats don't have any problem at all with starting and idling, because it's rare for a cat to be completely blocked. Usually they'll stop it from breathing at 2K RPM's and up, depending how bad the restriction is. The vacuum test is conclusive, although it won't tell you anything about the location of the blockage, just that you have one.
https://www.harborfreight.com/search?q=vacuum%20gauge

98_Q45
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VStar650CL wrote:
Tue May 21, 2024 6:14 am
Most cars with cloggo cats don't have any problem at all with starting and idling, because it's rare for a cat to be completely blocked. Usually they'll stop it from breathing at 2K RPM's and up, depending how bad the restriction is. The vacuum test is conclusive, although it won't tell you anything about the location of the blockage, just that you have one.
https://www.harborfreight.com/search?q=vacuum%20gauge
Okay, makes sense. Well I’ll report back hopefully with some findings.

98_Q45
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So I took it in today for a diagnostic but, still doesn’t seem to be any certain issue determined yet. Tech does believe it’s the transmission though. However not sure why it’s not giving off any transmission codes. Just the knock sensor and oxygen sensor heater wires for the post cats. Also suggested maybe thermostat or radiator may be plugged up due to the temp gauge going up after driving in hot weather and then idling with the a/c on. But I’ve changed those 2 things already.

I’m wondering if it’s related to some coolant stop leak I used awhile back that kinda clogged my reservoir tank. That’s when I thought it was head gasket instead of the leaking heater core hose. But since then I’ve replaced radiator, thermostat and heater core. Both electric cooling fans are working properly too.

I’ve read elsewhere on another forum for newer Infinitis that maybe the fan clutch can bind and cause similiar issues. I’d be hard pressed if it’s something as simple as that (it would be 2nd time replacing considering the last one I brought started binding too).

98_Q45
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Does anyone have a suggestion at this point? I don’t feel like I should be talked into a new transmission (which at this point not sure actually exists) without any codes. I would be hard pressed to have that done and the problem still persists, so I don’t think I can even remotely consider it.

It still seems like 0.14 volts might be too low for rear oxygen sensor. But not sure if that means the cats are clogged.

98_Q45
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And the other too: the issue is the one thing, but not being able to get a proper diagnostic is the other. I’ve been to 3 local shops and nobody seems to have a for sure answer what’s going on. I keep hearing theories but not actual, “this is what’s happening”. Not to mention, 3 places have claimed to not be able to get into the ECU to communicate. Whereas 1 shop and my own $5 Bluetooth connector and phone is able to plug in and read consistently. But oddly enough, I can only “clear” the codes on my android phone (which I originally used to do screen mirroring on the aftermarket dvd player), but not the iPhone. But it’s definitely not anything wrong with the ECU not connecting.

The whole thing is just upsetting. I would hate to just “throw it away” because I know, it knows what’s wrong with it. I’m just more annoyed I can’t find real knowledgeable mechanics. Like they know, but they don’t know THIS particular model.

Anyhow, think I’m going to get a 2nd opinion from an exhaust shop and see. However I’m not trying to spend $1,500 on both exhaust lines. I’d be more willing to throw 2 aftermarket cats or a section and see what it do. I just don’t believe the ECU would lie and not give codes for the transmission at all.

fontana dan
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Have you tried driving it with the front o2s removed, to see if it eliminates the problem? Buying the hardware to do an exhaust back pressure test would be a lot cheaper than throwing cats at it.
I don't think a clogged cat would give an intermittent symptom anyway, but who knows. I think a transmission problem would also be unlikely but not impossible. To diagnose that would probably take a very meticulous and logical approach. Have you paid attention if the problem shows itself in a particular gear, or with the torque converter locked or unlocked?
FYI the transmission in the Y33 is basically lifted out of a Frontier. Of course it has unique implements for the Q45, but the internals are not an uncommon at all.

98_Q45
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fontana dan wrote:
Mon May 27, 2024 4:04 pm
Have you tried driving it with the front o2s removed, to see if it eliminates the problem? Buying the hardware to do an exhaust back pressure test would be a lot cheaper than throwing cats at it.
I don't think a clogged cat would give an intermittent symptom anyway, but who knows. I think a transmission problem would also be unlikely but not impossible. To diagnose that would probably take a very meticulous and logical approach. Have you paid attention if the problem shows itself in a particular gear, or with the torque converter locked or unlocked?
FYI the transmission in the Y33 is basically lifted out of a Frontier. Of course it has unique implements for the Q45, but the internals are not an uncommon at all.
Just seeing this now…

Like I mentioned, I don’t have the tool to remove the front oxygen sensors. But it’s on the way, so I can take the rear ones off because I think they were rewired wrong for so long, the heater circuit isn’t working anymore.

At this point, the problem persists regularly. It went from an occasional thing to now an all the time issue.

It always seems to occur once the engine reaches its exact operating temperature. The car can be running fine for a couple minutes, then begin feeling like I’m towing a trailer the next minute. There’s no particular time it happens, other than once engine reaches operating temp. I’ve done thermostat and water pump before, and being it’s such a messy job to do both, I don’t want to go that route.

I’ve never had this issue with a vehicle before, so it’s very frustrating. I’m also having a hard time finding mechanics who can diagnose it. I just drove it today for first time in a week with the new fan clutch (which is giving me a new headache because the belt has been all squeals first thing in morning startup but, I think that’s moreso due to some coolant spilling on the belt…and I had to clean it and adjust belt tension). But the issue hasn’t gone away. Still struggling to accelerate, and running hot.

I’m going to do these oxygen sensors on the rear and also check for a ground strap that might have been broken. As for exhaust blockage: can’t I check that by using the voltage readings on the rear oxygen sensors?

On top of that, I’m not getting a whole lot of emotional support with this lol. Mechanics in my area are more 70s pickup truck guys. They keep throwing out the idea of getting another car or that it’s too high on miles, all I need is the issue figured out. I’d hate to even sell it to someone with this issue, because I wouldn’t want to buy something with an undiagnosed issue.

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VStar650CL
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Issues with the O2 sensors often show up only when the engine reaches temperature. When the engine is cold the ECM runs the injectors "open loop" and isn't looking at the cats or sensors, it's using a map in memory. Once the temp comes up it will attempt to run "closed loop" using the front O2's for mixture guidance. If those aren't working right, the car will poop out or misbehave as soon as it reaches temperature.

98_Q45
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VStar650CL wrote:
Sat Jun 01, 2024 5:17 am
Issues with the O2 sensors often show up only when the engine reaches temperature. When the engine is cold the ECM runs the injectors "open loop" and isn't looking at the cats or sensors, it's using a map in memory. Once the temp comes up it will attempt to run "closed loop" using the front O2's for mixture guidance. If those aren't working right, the car will poop out or misbehave as soon as it reaches temperature.

Ah, makes sense. Sounds like you have a bit more knowledge of this than what I’ve had so far lol.

I’m going to see what properly replacing and wiring the rear 02 sensors changes. The front o2 sensors aren’t throwing any codes though.

Will keep updated. Issue seems pretty persistent. Like f***, this sucks. If this issue weren’t going on, the car would be in such great shape. I’ve replaced so much and all I need is a paint job and to figure out why it doesn’t want to move when I press the gas lol.

The transmission or catalytic does seem to be a culprit. When it’s misbehaving, the RPMs go up slowly and then DROP back down. And I can feel a hard shift accompany it. But of course, symptoms aren’t always a diagnosis. And I’ve changed fluid and filter, all looks good. I do have a minor transmission fluid seep around some electrical sensors halfway underneath the vehicle. Idk if that’s something adding to it, but again: no transmission codes at all.

I’m just over it, after this oxygen sensor and ground strap look over: if it’s not working right I’m just going to drop it off to Infiniti and tell them I don’t want it back until they figure out what’s wrong lol.

The problem with that is, the bill may come out to $1,000 and then if I can’t pay it I’m f***. That’s why I haven’t been too adamant about having the dealer figure it out (and I’ve learned they aren’t necessarily better than any other shop. They just get the “license” to sell Infiniti, they aren’t actually the Infiniti makers themselves). Diagnostic work is not cheap, and I know if they have to really do some digging: it might cost more than I expect. Had the same issue with my Cadillac: a simple diagnostic turned into $1,000 and the problem still wasn’t fixed. Gotta take it to them again this week.

So I’m trying to be conservative lol.

fontana dan
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I would think that simply unplugging the front o2 sensors then driving the car would keep it from going into closed loop, thus giving you some insight possibly...
Logging the data from them would be easier. My 1997 had a dead rear o2 sensor and it did not affect drivability whatsoever.
I have noticed that the engine in my car seems to get kind of "hung up" around 2100 rpm when accelerating in 3rd gear. Its like a dead spot where the throttle response just goes away, but as soon as it hits 2300 rpm it takes off.

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VStar650CL
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We have a saying in the business, "the front O2's are for the engine, the rear O2's are for the government." Except as a cross-check for the front sensors, the only thing the rears do is monitor the health of the cats. So no surprise that your dead rear caused no performance issues.

Pulling the fronts will cause constant open loop, but it may also put the car in a reduced power mode. So it may or may not prove something. it may at least prove the problem is related to closed loop if there's no behavior change when warm with the fronts disconnected.

98_Q45
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Thanks for the inputs. I just now got an oxygen sensor socket, but that’s going to be for the rears just to get those put in new and properly working, that way when I go to another diagnostic, they won’t talk me into changing out the rear oxygen sensor just because it shows a code.

And I damn sure don’t want to get talked into changing knock sensors. All I think it’s doing is detecting knock, from somewhere.

New fan clutch and lower temperature thermostat on, will drive around in the heat and see how it holds up. However the “Hangup” issue when giving it any gas so far, still seems present soon as I hit operating temperature. Not sure if it’ll continue to run hot though.

I got it to go away before, but I can’t recall exactly what it may have been. I think throttle body cleaning seemed to help last time. I might have to revisit the air intake and maf sensor area. But again, no codes for that.

98_Q45
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Well I think I finally made a breakthrough today. Reading into the FSM again, I came across timing adjustment procedure and looked into a few articles on that.

Turns out, my camshaft sensor was way off center. I actually removed that in the past because it was leaking oil from a cracked gasket (I had a feeling it would cause trouble removing it) but I didn’t realize it had to be adjusted similar to the throttle position sensor. So I had just bolted it back on, but it should have been lined up in the middle. However, I don’t necessarily recall it giving me trouble at that time. But I had some other things going on so perhaps didn’t notice.

I think I either had the timing too advanced, or too “retarded”. I didn’t have the money or time to buy a timing light or find someplace to check it…but I did play with it a bit using the FSM procedure, while reading live data on the advance timing.

I suppose you can’t tell what the timing is using the scanner, but the ecm shows a bit of change when slightly moving.

Took for a drive after a couple on/off cycles and it seems to finally be working like a charm. Just sucks that I couldn’t find the right place to go to, who could check and adjust the timing. Cleared codes but will see which ones pop back up.

Also went to replace rear oxygen sensors just to try and clear heater circuit malfunction: but I can’t get those damn things to budge. Caused me the same issue last time I tried. I can’t get enough leverage, and the only way is using an offset attachment. I brought a big 1/2” drive socket online, but it doesn’t fit with the transmission pan in the way.

But if this ignition timing adjustment fixes the issue: I’m not worried about anything else. I need a break from DIY lol, I’m tired and fatigued. But I had a feeling this was a simple issue that simply went overlooked.

Will see though if it the problem STAYS away lol. It has a way of coming back around but, this time I think it’s resolved.

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:dblthumb:

Ryantzer
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I think the rear O2 sensors are not related to your issue, since all they do is monitor the functionality of the cats and have nothing to do with how the ECU controls the engine. Knock sensors are a common issue on the Q45s so if you're getting that code again it's probably likely they need to be replaced. if you're concerned about the cats being clogged or non-functional try a product called CataClean - I'm a long way from being a fan of the 'fix in a bottle' products as 99% of them are snake oil, but I've used CataClean successfully on two different vehicles that were throwing low-efficiency catalyst codes.

Do you have a copy of the factory service manual for your car? It contains diagnostic procedures for every code you'll ever encounter, and was written by the same people who designed and built your car, so it's an invaluable resource for maintenance and repair info.

98_Q45
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Ryantzer wrote:
Tue Jun 11, 2024 11:39 am
I think the rear O2 sensors are not related to your issue, since all they do is monitor the functionality of the cats and have nothing to do with how the ECU controls the engine. Knock sensors are a common issue on the Q45s so if you're getting that code again it's probably likely they need to be replaced. if you're concerned about the cats being clogged or non-functional try a product called CataClean - I'm a long way from being a fan of the 'fix in a bottle' products as 99% of them are snake oil, but I've used CataClean successfully on two different vehicles that were throwing low-efficiency catalyst codes.

Do you have a copy of the factory service manual for your car? It contains diagnostic procedures for every code you'll ever encounter, and was written by the same people who designed and built your car, so it's an invaluable resource for maintenance and repair info.
I’ve tried every damn bottle of catalytic converters cleaner lol. Probably went thru about 4-5 now over the last couple years.

However like I mentioned in previous post, I don’t think the cat is bad at all. Maybe it is old, but not clogged. I never got any codes for efficiency of catalytic though.

I rewired my oxygen sensors, couple years ago I had them replaced at a shop and the guy completely had them all mixed up (not really his fault since the previous owners must have cut the connectors instead of just buying one with them on). But it was like that for years before I finally decided to just do it myself (and I was charged $127 for that work that wasn’t even done right. But the guy who did it doesn’t work there anymore, another issue with where I live: mechanics come and go)

I have the FSM that I download and can read on here. That’s how I was able to figure out the oxygen sensors wiring colors were off. So for the longest time I had steady 0 volts on one, and 1.28 volts on another. Now I have proper readings of them, and I added a connector from eBay just to get it off hard wiring. The front’s were fine, I had those replaced around the same time, and they had original harnesses.

But like I said, a simply adjustment of the camshaft sensor to get my timing right seems to have been the problem all this time. However I’m still getting codes for knock sensor and heater circuit on rear oxygen sensor. I don’t live in an emissions state anyway so not worried about it.

I replaced a bad knock sensor on my maxima awhile back, it didn’t do anything special for performance but clear the code and maybe a couple extra miles to the gallon. Which isn’t bad but, the work to do it especially on the Q: not worth it. However those are the only 2 check engine codes left. If I got those two out the way, I would be check engine free. But I have 2 other vehicles, trying to chase a check engine light is: tedious, especially when it doesn’t always fix the actual issue.

Now, hopefully on to alignment and paint job lol.

fontana dan
Posts: 279
Joined: Tue Jun 21, 2022 11:10 pm
Car: 1997 Infiniti Q45
Location: Tennessee, USA

Post

I'm glad you finally got to the bottom of your problem. These cars are too much fun to drive, to be chasing stupid problems like that!


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