Multi Cylinder Misfire Code - could it be the transmission

[renkema]

There is a more detailed thread I started about 1 &1/2 ago on getting knock sensor and multi cylinder misfire codes. After multiple responses (and even purchasing new plugs and knock sensors which I have not installed), I'm still not quite sure what the issue is.

I decided to continue to drive it as was and although I was not getting the SES light I was occasionally getting a jerky motion as I went uphill or down which was identical to the symptoms that caused the aforementioned codes registered before. Given the responses to my earlier post that there are a lot of things that can cause the Knock sensor and multi misfire codes, I started wondering if the problem was not the engine, but the transmission.

To retrace my steps, I did not have this issue until I took it to the dealer for other service and they said the transmission needed flushing and refill. Today, I drove the car with the O/D off and the periodical jerking went away. It was replaced by the smell of hot transmission fluid, so I decided to look at the fluid for color and amount.

The fluid look as any transmission fluid should (not brown in any way). However, I did notice that the fluid appeared to be drastically overfilled. With the dipstick cleaned, fully inserted, and then withdrawn, I register the level to be about 1 & 1/2 inches above the top of the hot mark. Note that the previous sentence says "fully inserted". I noted that there is a hold down clasp that has to be pulled back in order to fully insert.

1st question: to test the trans fluid level, should the stick be fully inserted or should it rest on the clasp.

2nd question: will an overfilled transmission caused hunting or shifting problems

I could not see any reference in the FSM to do anything but insert it all the way. I did see that it cautions to "not overfill" on page 20 of FSM section MA.

Any thoughts????

[renkema]

Follow-up: Problem apparently solved

Recap: The KS (P0325 &P0330) and and Multi-Cyl (P0300) SES codes occurred after throttle body cleaning service by the dealer. I was getting a jerking motion that I thought was related to the Misfire codes. It turns out that the jerking motion was NOT the engine misfire, but the tranmission. The problem was the throttle position switch/sensor (see FSM page AT-99) which plays a role in governing the gear changes. The dealer identified that they had not set it correctly (not sure whether they adjusted the switch or sensor) when they did the throttle body cleaning and that was causing the "hunting". They reset it and I drove home with NO issues. The transmission fluid level was fine as I misread the amount (needs to be running AND hot).

The dealer still thinks there is a coil issue, but said they cannot determine which one. They think all should be replaced to properly fix. They do NOT think there is a KS issue although the codes are registering. The P0300 is not registering currently and the SES light is not illuminated.

I'm going to do nothing for a while and see what happens, if anything.

Thanks to all for their input and comment on my other post as that helped me avoid much time and expense (although I did buy the complete knock sensor setup and new plugs which are now sitting in my personal inventory)

As with all high end autos, "in for a penny, in for a pound".

[Q45tech]

Multicylinder misfire is guessed by ecu by looking at the O2 sensor switching or the lack thereof at the appropriate time.

A misfire is a misfire usually defective coil/coils from abuse [during spark plug change] or oil in plug well or just a failure from natural causes.

[maxnix]

To retrace my steps, I did not have this issue until I took it to the dealer for other service and they said the transmission needed flushing and refill. Today, I drove the car with the O/D off and the periodical jerking went away. It was replaced by the smell of hot transmission fluid, so I decided to look at the fluid for color and amount.

The fluid look as any transmission fluid should (not brown in any way). However, I did notice that the fluid appeared to be drastically overfilled. With the dipstick cleaned, fully inserted, and then withdrawn, I register the level to be about 1 & 1/2 inches above the top of the hot mark. Note that the previous sentence says "fully inserted". I noted that there is a hold down clasp that has to be pulled back in order to fully insert.

1st question: to test the trans fluid level, should the stick be fully inserted or should it rest on the clasp.

2nd question: will an overfilled transmission caused hunting or shifting problems

Be sure of what constitutes a fluid exchange in the dealer's mind. Drain and refill won't do it. Pandrop, clean filter and one time use bolt replacement mandatory. If the fluid is not pinkish bright red, serious deterioration has occurred. Brown fluid is expired fluid and accellerated wear and damage has occurred.

[renkema]

A misfire is a misfire usually defective coil/coils from abuse [during spark plug change] or oil in plug well or just a failure from natural causes.[/QUOTE]

So I need to go the new pack route. You may be right as later today, the missing/jerking sensation returned intermittently. I guess I need to find a thread on changing the packs and/or consult my FSM.

If it is the coils all along, I'm happy to eat crow as long as the $1500 in coils makes it work properly.

It's still a little difficult to accept that with all the power of the ECM, the offending coil/coils could not be i.d. by the dealer (even with a Consult).

[maxnix]

1.) So I need to go the new pack route. I guess I need to find a thread on changing the packs and/or consult my FSM. If it is the coils all along, I'm happy to eat crow as long as the $1500 in coils makes it work properly.

2.) It's still a little difficult to accept that with all the power of the ECM, the offending coil/coils could not be i.d. by the dealer (even with a Consult).

1.) Not necessarily, and most certainly not for all of them. There is a thread on changing them, but it is quite easy.

2.) A real ODB II diagnostic tool will tell you which cylinder is misfiring, then you can interchange the coilpack to see if the fault moves or not. Too much effort and time for a $125/hour dealer. Did the dealer's Senior Technician look at it, or do they even have one?

Fix the known issues (valve cover gasket) first.

[renkema]

2.) A real ODB II diagnostic tool will tell you which cylinder is misfiring, then you can interchange the coilpack to see if the fault moves or not. Too much effort and time for a $125/hour dealer. Did the dealer's Senior Technician look at it, or do they even have one?

Fix the known issues (valve cover gasket) first.[/QUOTE]

The senior tech looked at it as I specficially asked to be introduced to him. I have an Toptak ODBII tool (I think it qualifies as real). I can't imagine that I would be able to i.d. the offending cylinder with that and the tech could not with the Consult. My tool currently is NOT registering ANY codes (the SES is light is not illuminated as well). The Misfire (MM), Fuel Sys (FS), Comprehensive Component (CC), catalyst (CM), Ox Sensor Heater (OH) monitors are all registering as supported and complete. The Ox Sensor (OS) and (EGR) monitor indicators on the OBDII are flashing. Per the tool, this indicates that the monitor category is supported but not complete. Not sure what that means. I'm not sure that my tool gives me much to work with unless the OS and EGR flashing is an indication of an issue. The car passed emissions inspection 3 weeks ago and I would think that since they use the OBDII sys that they would have kicked it if an issue was being broadcast by the ECM.

I'm assuming I could drive around with the OBDII attached and read it when I feel the car jerk as before and see if anything registers as I think the ECM will hold a fault for a period of time and then release it depending on the type of fault. Is that correct?

I agree that I would only get probably 2 coils (in case it is more than one) and go thru elimination as you suggest.

Valve Cover Gasket? that's a new one. Are you suggesting that may be the culprit?

Lastly, I could not find the coil replacement link and do not see the procedure in the FSM (probably too basic to print). I can probably figure it out but if you could point me to the thread, I might save some time. Thanks

[infiniti97_owner]

Hello Folks,I have a 97 Infiniti Q45 with 95K miles on it. Recently changed the spark plugs on it at firestone ( I know ... Big mistake). They used Bosch Platinum Plugs...I had originally started a thread for my issue but someone suggested that I search for this thread, and the symptoms described by Renkema pretty much mirror what I'm expreriencing.I started having the problems after driving for 500 miles on the new spark plugs.... So it wasn’t instantaneous.I have taken it to Autozone couple of times, the first time they diagnosed the following codes

P0300 Random Misfire P0325 Knock Sensor, Bank 1 P0330 Knock Sensor, Bank 2

So I took the car back to Firestone and asked them to check it out... They said the problems were not related to spark plugs - they performed their diagnostics and said everything looked fine.... So they disabled the codes and charged me $85 . This was about 2 weeks back... But I still continued to experience the symptoms- surprisingly Firestone tech's could not see the same ???Since the check engine light was not coming on I neglected the symptoms and drove, but few Days back the Check engine light came back on so I took it to Autozone again- this time the following codes showed up in their Diagnostics.

P0110 IAT Sensor P0325 Knock Sensor, Bank 1 P0330 Knock Sensor, Bank 2

So I went back to Firestone one more time.... They said that they would charge me $85 one more time to perform a diagnostic AND IF the problem was not related to Spark plugs work that they had done. I decided not to get the diagnostics done until I had a better understanding of this issue, hence I'm here asking for your help and suggestions.

I also read in Renkema's post that his problem started after throttle body cleaning service by the dealer- but I have no knowledge of this service being performed by firestone.My question is 1. Could this be a problem related to the spark plugs that I got changed, if so is there a way to convince to firestone about it ?2. If not, any suggestions/ideas/direction of why the car is experiencing this problem ?

TIAMK

[renkema]

[QUOTE=infiniti97_owner]Hello Folks,I have a 97 Infiniti Q45 with 95K miles on it. Recently changed the spark plugs on it at firestone ( I know ... Big mistake). They used Bosch Platinum Plugs...

P0110 IAT Sensor P0325 Knock Sensor, Bank 1 P0330 Knock Sensor, Bank 2

There's ample opinion on this forum that only the NGKs should be used. Period.

Now you're getting 110. I would be suspicious that they/someone did not re-hook up the Air temp sensor on the air intake (next to the air filter) and that's why you are getting that code.

I do not feel any closer to resolving my issue than I did a month ago. Unfortunately, I am starting to smell trans fluid when I get out of the car after a drive. The transmission may be leaving the station.

Sorry I could not be of more assisitance other than to say the jerking/missing apparently weighs on the transmission. My time spent trying to self diagnose, may have cost me a transmission (I only have 90k on mine).

[maxnix]

I have a 97 Infiniti Q45 with 95K miles on it. Recently changed the spark plugs on it at firestone ( I know ... Big mistake). They used Bosch Platinum Plugs...

.....

My question is 1. Could this be a problem related to the spark plugs that I got changed, if so is there a way to convince to firestone about it ?

Rip them out immediately and replace with the correct OEM recommended NGK. You have a valid issue with Firestone as they installed the incorrect plug. But I would cut them free before they do any further damage to your car and gouge you for it.

Spark plugs could be the problem, but even if they are not, they have proven to be fatal to VH series engines. Search and read.

[renkema]

[QUOTE=maxnix]Be sure of what constitutes a fluid exchange in the dealer's mind. Drain and refill won't do it. Pandrop, clean filter and one time use bolt replacement mandatory.

After the tweaking of the throttle position switch/sensor 3 days ago, I have not had the jerking/missing. I do have a transmission fluid smell, but the color looks fine. No codes in ECM while engine off.

In reference to your comment above, I called the dealer and they said they only did a drain and fill and that opening the transmission up to clean the "screen" would cost "hundreds and hundreds" of dollars. So now I'm left with thinking that the 2 months of jerking that had occurred until now may have damaged the fluid and I need to exchange it, but my dealer doesn't appear to be the place to go.

I see the plug on Joe's site but no reference to the filter/screen. I'm assuming that is a reuseable item.

The transmission fluid posts seem to recommend a "BG" flush and replace with synthetic M1, but I'm assuming I would need to clean the screen/filter myself prior to such a procedure. I guess while I'm at it, I've seen refernece to an in-line cooler that I did not see on Joe's site. What would you do in my case?

[Q45tech]

The screen filter is not reuseable due to metal getting wedged where you cannot see it..................cheap to replace.

The pan drop is to clean the magnet and wipe the pan clean, while I'm in there I use spray brake cleaner IF I SEE any varnish on the valve body, etc.

These things need to be done when the transmission is 2 years old [30k] to materially extend life waiting too long allows too much damage to occur and nothing will repair gaskets and clutches and worn tolerances except replacement.

[maxnix]

In short, read all of Q45tech's previous posts, including the links.

Dealer's are not motivated to maintain a car for the long haul. If it passes the OEM or extended warranty period, they are like Pontius Pilate and wash their hands of it.

Let me give you a really good hint. You are not that far from T-3. Ditch your dumb dealer.

[renkema]

Q45tech: "These things need to be done when the transmission is 2 years old [30k] to materially extend life waiting too long allows too much damage to occur and nothing will repair gaskets and clutches and worn tolerances except replacement."

Thanks Guys, No argument on the dealer at this point as I have had NO more jerking since the TPS was adjusted. I'm now convinced that the throttle body cleaning was a sloppy job and upset the setting. T3 is a 5 hour drive. Maybe that's where I'll go when the transmission leaves the station.

But until then, Q45tech, are you saying that the pan drop and clean is futile if this was not done at the 30k (I bought it with 45k on it) or are you saying do it yearly after the 30 k (hopefully the later). I would like to think I can have the screen replaced and service done as you suggest (just not by the dealer for "hundreds and hundreds of dollars") and see some benefit in prolonged performance. I'm assuming this is something I could only do with a lift and hence should have it done by a shop (maybe T3). If I could do the work (I have ramps and jacks), please direct me to a post detailing the procedure if one exists. I will go through your posts myself as Brian suggests.

On the bright side, I did not spend $2000 in parts at the dealer on coils (although I am the proud owner of new uninstalled KS & harness and a full set of NGKs).

Thanks for all the help!!!

[maxnix]

Dropping the pan, cleaning it and replacing the filter is a 30 min - 45 min job at worst after it is on the lift.

http://www.bgfindashop.com

After the transmission is toast, it will be a lot more expensive to get the car to Atlanta.

[infiniti97_owner]

Hi Brian,Since i spent about 200$ already on the spark plugs, could i replace the Bosch plugs myself using the right NGK plugs, if so, is there any useful site or manual that shows a do it yourself type of directions.My Neighbor changes the spark plugs on his camry's and has offered to help me out, but need a little direction on how to do it.Appreciate your help.

MK

[96Qowner]

Try here:

zerothread?id=117157

[goody90q45]

....could i replace the Bosch plugs myself using the right NGK plugs, if so, is there any useful site or manual that shows a do it yourself type of directions.

Not sure if you've got a copy of the Factory Service Manual but it should be of some help:

http://phatg20.net/modules.php...id=62

[maxnix]

Easy with an accurate torque wrench and some high temperature lubrication. Dont get any dirt down the spark plug hole while the plug is out. Be careful undoing the coilpack connectors.

Don't force, overtorque, or crossthread anything into aluminum. Go slow and do it correctly.

[infiniti97_owner]

Hello Folks,As suggested by Brian got the Spark Plugs changed to the NGK's. However, the check engine light still shows....again went back to AutoZone to diagnose. These are the following codes that show up now.

P1110 - IAT Sensor (D/C) Open/ShortP0400 - a malfunction exists in the exhaust gas re-circulation flowP0325- malfunction exists in the electrical circuit for knock sensor 1P0330 malfunction exists in the electrical circuit for knock sensor 2.

Since i don't know much about these codes or how much it is going to cost to get it repaired, was wondering if the folks here have any suggestions or direction.Appreciate your help!MK

[renkema]

update- 2 weeks later and still no jerking/lurching or SES light, so the TPS must have been the culprit.

Unfortunately, I'm smelling transmission fluid. None on the floor and the fluid on the stick is not hot and is pink (doesn't appear burned), so I'm stumped. There's even the smell of transmission fluid when I turn the car on (coming thru the vents).

The dealer at their suggestion did a "flush and replace" back when this whole supposed problem with the KS and coils started. Any thoughts on trouble shooting a bad transmission service (fluid only).

Althought the car's running perfect now, I feel I'm on the verge of a big problem if I can't figure out what's causing the smell. Any thoughts?

[maxnix]

Check your valve cover gaskets all the way around each one.

[renkema]

update-still no more missing/lurching, so the TPS must have been it.

I continue to get the smell of AT fluid. The fluid is still bright pink, but the hot evel has gone from the top mark to the bottom mark in about 4 weeks time.

To recount, the dealer did the TB cleaing and screwed up the TPS. They also did a flush/replace on the AT fluid. I'm thinking there must be loose connections somewhere in the AT fluid flow, but I do not know where to look and feel like I probably need to have it running AND elevated to pinpoint any leak.

Brian suggested looking at the valve cover gasket, but I'm not sure how that could be the issue unless like coolant the AT fluid courses through the block. Maybe he was refering to another gasket.

If I can get through this, I intend to part ways with my dealer and and drop it off to Q45tech and T3 when I have a trip through Atlanta later this spring as I know it needs better care than my dealer can provide.

Any thoughts on the AT fluid leak so I can be knowledgeable when I approach the dealer on this issue??

[maxnix]

There is one hose to the tank in the radiator and one back. Don't think there is any intervening filter.

Not exactly rocket science either way.

[renkema]

I've installed an AT on an late 80's accord and that's exactly what I remember. Other than pan/bolt/gasket issues, drain plug, radiator hoses, or fill tube, I would not know where else to look. I'll check those. Thanks

[renkema]

Found the leak.

The send or return hose bolt (not sure which one) at the transmission has a leak. The other send/return is bone dry as are the connections at the radiator.

Now the problem. This bolt seems TIGHT! Moreover, it's in an impossible spot to get to. I can get a 3/4" around it but there's minimal room to move without taking off the transmission mount.

I'm assuming when I get it loose that I need to replace the copper washers. Does the bolt have loc-tite applied. What's the proper way to get this bolt tight?

Brian, you were also right about other leaks. I found small oil leaks on the lower side of each head gasket. If memory serves, I can't simply tighten the mounts but have to get new gaskets. I'll send you some pics as I do not know how to post them here.

[maxnix]

Definitely don't over torque into an aluminum head!

You'll be sorry.