00 Q45 Quirks or Problems Help Please!

[JohnCampbell08]

Hello everybody, I have a 00 Q45 145k with a few small issues (hopefully small).

The car runs perfectly at times, and then all of a sudden, it feels like a misfire. There is a pretty serious studder when accelerating, and the idle is rough with small amount of jerking. The wife said that the traction control light and slip light came on once before, but did not come on since I cleared the codes the first time. And the second time it was running bad like this, the lights did not come on.

I pulled 4 codes :

P0340 Cam Position sensor
P1320 Ignition system or misfire
P0400 EGR Valve
P0325 Knock Sensor 1

My research has shown me that the CPS is pretty serious, and can be causing these problems. But I cannot find a DIY yet...I will keep looking.

I was reading that the ignition system code could be related to a coil, but how can I narrow down the search? I don't want to overhaul every single coil, esp if my problem happens to be due to the CPS or other.

The EGR valve is mainly for emissions....for the sake of this thread, we can ignore this issue for now, since all I care about is having the car running right, and then I can chase down the gremlins.

I have been reading that the knock sensors are very common issues with these cars, and I am sure mine could be due for them. Could the other problems such as the misfire throw the code for the knock sensor though? So in other words, my knocks could be working fine since they are reading that the car is misfiring?



Since I have not worked on Infiniti before, I would usually start with trying to correct the CPS first. Hopefully this could be causing my misfire, bad idle, and sluggish acceleration? Could it also be causing the ignition code and the knock code?

Car recently drove on a long road trip with no issues. Back in town for about 2 weeks, and then this happens.

LAST THING, this temperature sensor is driving me crazy. The needle jumps up and down with every gas pedal movement, sporadically, with no rhyme or reason. Are these common issues with these cars?

Thanks for everything in advance!

[lamsv]

Knock sensors usually don't cause those symptoms. When they fail, the ECU gets conservative with the ignition timing, as it can't get an accurate read on the quality of the combustion. I would replace those, as they will restore the "peppy" fell of the car (changing mine did at least). It is NOT an easy job though. Removal of the intake manifold is the recommended method (though, I was able to replace them by just removing a few items from the front of the motor, and patiently snaking my hands under the intake manifold).

P1320 and the CPS are related. I was throwing a P1320. Everybody told me it was a faulty ignition coil pack. But, from all the tech's I talked to, usually the ECU will throw a code locating the specific coil pack that is bad. Mine wasn't. The only information on the CPS that I could find was a thread concerning a rough running engine in a Maxima. The owner replaced the sensor, eliminating all problems he was having (rough idle, stumble when pressing the gas, engine dying immediately upon starting). I was having all the same issues. The cam sensor is located on the driver's side cylinder head, at the very front (just behind the radiator). In my case, a leaking valve cover gasket had leaked oil all over the sensor. Remove the intake tubing first. Then remove two bolts that hold the sensor in place on the cylinder head, Pull and turn the sensor to remove it from the cylinder head. I removed the plastic sensor housing, gently cleaned the internals, applied a new gasket, carefully cleaned the tip of the sensor, and reinstalled it. 2 months have gone by with out the P1320 code coming back (knock on wood). I would first remove the sensor and clean it. That is not a permanent fix (I would just bite the bullet and buy a new one at some point soon), but if cleaning it fixes the major problems, then you know that is the issue and plan accordingly to buy a new one.

Hope this helps!

[JohnCampbell08]

Huge help! I forgot to mention that I think the valve cover gasket is leaking too, so this would make all the sense in the world!

Glad to hear it could possibly be a very easy and possibly free fix, at least for now, until I tackle all the maintenance at once

[maxnix]

You will need to read paranoidjack's KS replacement thread.

[bruce2]

Before or after you have done everything mentioned above, if it still happens, you may want to try an different gas station. My '92 starts having the same symptoms as yours since I came to this name brand station. But I was not 100% sure because it is not the first time pumping there, however, I figure it could have been some contaminants settle on the bottom of the underground tank since the station was there for a long time. So I went fill up at the newest and busiest station, the big W store, near by and the problem went away. From then on I pump from there for all my cars. This could have been a coincident but worth to try.

[JohnCampbell08]

I cleaned off the sensor today...I wonder if it will do anything different.

It looks like in order to replace the Knocks and clean/replace the EGR, the manifolds have to come off. And then I might as well do the valve cover gaskets...looks like a lot of work.

When I pulled codes today, only the knock and Ingition misfire codes came up. Could the knock sensor also make the misfire code pop up?

[maxnix]

Could the knock sensor also make the misfire code pop up?

Not that I have seen, but I haven't seen that many codes, but I have seen KS and cylinder specific mis-fire codes and they were unrelated.

[JohnCampbell08]

Ok, thanks.

Well the wife was driving to work and it went crazy again. The check engine, slip and misc lights came on at the same time and the car ran rough...

So cleaning the sensor didn't do anything different...and since the CPS code didn't come back, the rough driving is due to something else.

My #1 priority is now fixing whatever is causing the bad accelerating/idle/lights. Should I chase down the misfire or the knock sensors first?

Thanks again for all the help so far, I really do appreciate it

[JohnCampbell08]

I tried messing with the CPS again by reading the FSM.

I checked for continuity on the plug, and if I checked correctly, the two wires to the right did show volts going through.

When I left the plug completely unplugged from the CPS, it would not start. As soon as I plug it back in, it started over.

So does this mean it's a coil issue? Why would my CPS trigger a check engine light if it seems like it is working?

[JohnCampbell08]

Just checked all the coils. I am pulling around 1.0X on all the coils, so judging by the FSM, all my coils should be good?

I am pulling my hair out trying to figure this out.

My research has shown me that the KNOCK sensors COULD throw the slip and traction light, but they all said that the car would run almost normally. Might lose mpg or the idle might be off, but mine is running like a misfire and seems more serious than the knock sensor alone.

BUT, the car doesn't ALWAYS run bad. Most of time it runs smooth. And I was getting 22mpg average

Plus I do have the P1320 and the previous CPS code, making me think the knock cannot be the only issue, but no idea on what to try next

EDIT, just pulled the codes, CPS is back. Probably from me starting it without the cps plughed in, but not sure. Maybe I should just change the CPS anyways

[JohnCampbell08]

Well today the car isn't starting at all. I'd imagine if a coil went bad, it would start and run bad all the time. Now it's not turning over at all.

I'm going to buy a CPS and see if it takes care of my problem.

Is it realistic to suspect that the CPS was on its way out, threw the CPS code, and ran rough for a few days until it completely gave out?

[VA99Q45]

You don't need to remove the manifold to clean/replace the EGR. You can do simple test to see if the EGR is holding the pressure. If it does and the temperature sensor is OK, then it may be the EGR solenoid is bad. To replace the EGR solenoid, you need to remove the manifolds.

Some of your problem maybe a bad coilpack. When I had 1 bad coilpack in my car. It idle rough and it stumble with quick acceleration. But I did not have the skid light. You can buy 1 good coilpack ($75) and start swapping 1 cylinder at a time to see if some of your problem go away.

I cleaned off the sensor today...I wonder if it will do anything different.

It looks like in order to replace the Knocks and clean/replace the EGR, the manifolds have to come off. And then I might as well do the valve cover gaskets...looks like a lot of work.

When I pulled codes today, only the knock and Ingition misfire codes came up. Could the knock sensor also make the misfire code pop up?

[TommyTank]

Similar situation. My valve covers started leaking at about 130k, I did not feel like doing it myself and had the gaskets along with the spark plugs done by an independent shop, good referrals and all. When I got the car back I noticed the occasional bump when stopped at a traffic signal especially with the AC on and a drop in mileage. I took it back, they drove it ~20 miles said nothing was wrong, no CEL.. so nothing they could do. At least the gaskets don't leak!

On older cars a misfire at low idle was usually a vacuum leak someplace, so I painstakingly went through them and found 2 miss routed hoses and multiple clamps not in place... I got mileage back to normal, but no real change in the occasional bump at idle. After going through articles in this, and other, forums I cleaned the MAF Sensor, put it back together with dielectric on the connector. No change.

The car has no codes stored and runs fine other than the misses at low RPM. I'm not certain but they seem to increase on hot days and when it's raining. I'm not going to mess with finding the coil pack, so I just ordered 8 and will swap them out next weekend. Over the counter I could not find the OEM Hitachi's for less than $89.00 and on-line I found them for $60. I'm also going to pull the plugs to see if they point to anything, and to ensure they were actually changed. I'll post my findings.

Other notes - I did get a traction/sport indication once a few years ago when I was between DFW and Houston and ran into a rain storm, but I figured it was the abrupt change in weather.

[paranoidjack]

where did you find them for $60?

[JohnCampbell08]

My CPS should be arriving any minute now. I'll update the thread once I see what happens...*crossing fingers

[bullittandy]

Can I complain for a moment? The purpose of an online forum is to share knowledge so why this new guy is getting roundabout answers is beyond me.
-knock sensor-search site for my write up about replacing without removing plenum. removing plenum is a HUGE job. done this job twice.
-EGR code-almost certainly a split rubber vaccum hose running to it. I made this repair for the 3rd time (on three cars) 3 days ago.
-misfire-its a coil, known weakspot on these cars, replace all 8 coils and be done with it. done this job twice
-valve cover gaskets, passenger is easy, drivers requires removing plenum or cutting a intake bracket off, 8 hours or 8 minutes-your call. again, done this job twice

good luck

[JohnCampbell08]

^thank you for the advice.

So I changed out the CPS...nothing changed.

Car still won't start....just turns and turns.

I double checked that all coils were within the ohm resistance, so if I did it correctly, the coils should be fine? Also, even if a coil went bad, wouldn't it start and run like crap, or at least hesitate when it's trying to start?

I pulled one of the coils out, stuck a screw driver in it, and placed it near metal to see if it would spark/arc. This is how I did it on my older cars....but I saw nothing. Should I try the other coils or is there something that gives power to the coils that could have went bad? So far I checked two and didn't see anything. Not sure if it's because I am getting no spark to any of the cylinders or maybe I am doing it wrong

[TommyTank]

where did you find them for $60?

PartsGeek... never used them before so fingers crossed.

[Skibane]

Also, even if a coil went bad, wouldn't it start and run like crap, or at least hesitate when it's trying to start?

Yep. Even if only one of the coils was still good, you'd still notice the engine attempting to start every time that coil fired. Something else is disabling the coils.

The fact that you saw a lot of other trouble lights on the dashboard - problems that wouldn't normally be related to engine misfire or no-start - is a clue. My guess is that a harness connector somewhere is loose.

Do you have a factory service manual? It would be very helpful in telling you which harness carries wires for all those functions - and which connector to check.

Knock sensors and O2 sensors are common failure items - One of them may actually be bad, and may not be related to the the other symptoms you're seeing.

[JohnCampbell08]

I have used the FSM link of the board a few times, but I don't own any manual.

But even if my knock sensors, o2s, and 1-2 coils went bad overnight, it still would TRY to start, and most likely start and run like crap...

My car never had issues before, then all of a sudden threw the codes above, and then it stopped starting...not sure if it is the same problem or different one

[Skibane]

Either download a copy of the FSM, or buy a $5 copy of it on CD-ROM on ebay, Amazon, etc.

Attempting to keep your Q running without it is a HUGE handicap - Basically, you're reduced to guessing and swapping out parts until you stumble on the real problem.

Aside from a bad harness connector, a broken or missing chassis ground connection is another good prospect. Without a decent ground, the ECM thinks those sensors are sending gibberish. For example, if anyone has done any body repair or major engine parts-swapping on the vehicle, it's quite possible that a ground bolt was omitted afterwards.

Again, the FSM will tell where each and every ground point is located on the vehicle, and which sensors are connected to each of them.

[JohnCampbell08]

I have been using the FSM on this site...

I double cHecked the grounds that are in the front of the engine, but I'll keep looking for others.

Just weird that it would all of a sudden go bad...if it was a ground, it was working fine for years presumably

[paranoidjack]

Have you checked all fuses for continuity with a multimeter? It's not the most comfortable placement and I found excuses to avoid checking it, but have had a few fuse issues with mine.

[JohnCampbell08]

I checked most of the fuses when I was searching for the fuel pump fuse to double check that was still ok...EDIT, I've checked all fuses under dash and under hood, all checked out ok

What gives spark to the coils?

My friend mentioned two things, an ignition control module and a relay for the ECM....not sure if these are relevant to our problem here, but I have been searching and searching and can't find anything.

I will continue looking in the FSM

[JohnCampbell08]

So I checked for voltage going through the power wire (red/green) wire going into the CPS (I checked on the wire before the clip) and I was not coming with any voltage...


CPS Harness by akureikami77, on Flickr

It looks like I may have a break in the wire somehow? Gotta figure out how to check the wire going from the ECCS relay and the ECM, even though I don't know where the relay is

[TommyTank]

Coils came in, put them in tonight.... before the replacement I was getting a more consistent miss at idle with it disappearing after the engine got above ~1200 RPM. Seems to have fixed it smooth idle no misses. Went for a test drive for about 20 minutes and idled in gear with AC on, no misses.. calling it done for now.

[willko1]

Can I complain for a moment? The purpose of an online forum is to share knowledge so why this new guy is getting roundabout answers is beyond me.
-knock sensor-search site for my write up about replacing without removing plenum. removing plenum is a HUGE job. done this job twice.
-EGR code-almost certainly a split rubber vaccum hose running to it. I made this repair for the 3rd time (on three cars) 3 days ago.
-misfire-its a coil, known weakspot on these cars, replace all 8 coils and be done with it. done this job twice
-valve cover gaskets, passenger is easy, drivers requires removing plenum or cutting a intake bracket off, 8 hours or 8 minutes-your call. again, done this job twice

good luck

Tell me more about this intake bracket? i need to do my valve covers and would not like to spend all weekend doing it. (2000 q45 110k) also have you had to replace your fan clutch at the same time for the cracked blade issues?