Check Engine Light Clearing..

[nuQ]

Undertook cleaning the entire engine of my new M45, which wasn't horrible to begin with, but looks a million times better. Got real inspired and took apart the entire air intake including the MAF and throttle body, and cleaned that out too. Well, did a real bonehead thing and put it all back together and started it up, and only then realized I forgot to hook up the plug to the MAF. Re-installed, but of course the check engine light was lit up. Drove it for a couple days, but it would not clear.

I took it to my independent tech and he hooked it up to the computer and cleared the computer. Drove it for a few hours (turned it on and off a couple times) but the check engine came back on. Took it back the same day and he cleared it again, but it is back on now. Is there something I'm missing, or is this a dealer issue at this point? Thanks

[SteveTheTech]

Did you have the code read or just cleared?

You might as well combine trips with this and the TPM problem you are having.

If it is related to your maintenance, I would suspect you have a Idle Air Control code after cleaning the gunk off of the throttle or left some gunk on the MAF hot wire. That would come with a driveability problem more likely than not.

[nuQ]

Yes, the code was for the idle air, I believe, and possibly the MAF too..? I do remember him saying the idle was showing, which would make sense with cleaning the MAF and throttle body. Obviously it was very noticeable that the plug was not attached when I initially started it up, but after connecting the plug, it has run fine since. Other than the check engine light, it seems 100%.... I think I will have to combine visits to the dealer to have both cleared, and/or repaired...

[svard75]

Perform the Ecu reset the idle relearn tb relearn reset and see if it clears for good. The instructions are in the following post throttle-response-t580046.html

[nuQ]

msvara-----thanks so much for the link.....and I will perform and let you know how that turns out. I saw in the link, someone discussing a transmission issue where the shift points do not seem to be where they should. Is this an issue for the 2003 transmission, as sometimes my shifts also seem to be slow, with a hesitation when the downshift should be quicker..? Wondering if this might be more a throttle position issue, or a trans issue.

Would it make sense to ask the dealer for any reprogramming of the transmission, or is that a non-issue? When going over the Carfax, I did not see anything indicating this was done under warranty....

[svard75]

I had no problems with my 06 car and the transmission shifted like an old lady with a walker. I then had a uprev tuner play with my torque management tables in the ECU and tweaked the shifting. It now shifts depending on how I drive it. If it's normal, it shifts normally. If I drive spirited the transmission shifts so hard and so fast it feels like a kick in the butt.

[nuQ]

I had no problems with my 06 car and the transmission shifted like an old lady with a walker. I then had a uprev tuner play with my torque management tables in the ECU and tweaked the shifting. It now shifts depending on how I drive it. If it's normal, it shifts normally. If I drive spirited the transmission shifts so hard and so fast it feels like a kick in the butt.

An "uprev tuner"? Is that something the dealer can do, or does it need to go somewhere else??

[svard75]

Seymore4 on this site could get you hooked up.

[nuQ]

Thanks, I will look up "Seymore4". I did the procedure for clearing the ECU last night, and the first step went well and I have the 'check engine light' turned off (for now....), but I'm not sure if the other steps were successful. When I got to the last step I could not get any indication that the ECU or Check Engine Light was acknowledging the procedure. But, at least the problem is cleared for now, so I'll keep everyone posted...And I will definitely look in the transmission, too.

[svard75]

Is the car idling better and quieter?

[nuQ]

The idle, and drivability is absolutely fine, and really has been as soon as I first re-hooked up the MAF plug. I have cleared the CEL (using the above linked method) about 3 or 4 times in the last couple days, and it will stay off for a couple start-ups, or (today) about a 15 minute drive, and then it lights back up.....again, noticing no difference in the engine at all when it happens.

I'm wondering if it's possible that something either in the MAF or the throttle body is off from the cleaning. With the MAF, everything was taken apart, and MAF cleaner was sprayed in and allowed to dry. For the throttle body, I simply used a rag and throttle body cleaner to wipe the plate and as far as I could reach my fingers in to clean. It wasn't really that dirty (either), so I'm not thinking that any larger pieces of dirt, grease, carbon, etc. got lodged in anything. Just strange that it clears everytime, and then will come back on in around the same time frame....15 to 20 minutes later, or a couple start ups later (if they are quick trips)??

[svard75]

Sounds like you have a bad part. I did this once and as with my older cars left the tv connected while I moved the butterfly to clean it out. They had to replace my tb.

[The00Dustin]

Perform the Ecu reset the idle relearn tb relearn reset and see if it clears for good. The instructions are in the following post throttle-response-t580046.html

Are these the same for the 03-04? I'm wondering if he can only get the ECU reset to work because the others are different.

Seymore4 on this site could get you hooked up.

I also thought Uprev wasn't able to reflash the 03-04. I guess Seymore4 can confirm that one when contacted, though.

[nuQ]

Perform the Ecu reset the idle relearn tb relearn reset and see if it clears for good. The instructions are in the following post throttle-response-t580046.html

Are these the same for the 03-04? I'm wondering if he can only get the ECU reset to work because the others are different.

Seymore4 on this site could get you hooked up.

I also thought Uprev wasn't able to reflash the 03-04. I guess Seymore4 can confirm that one when contacted, though.

This would make sense, since I could only perform the ECU reset (1st instruction on list), which did clear the CEL for a short time. I could not get confirmation (either from listening or from the CEL) for any of the other steps...

[atlM35]

Can you list the specific trouble codes?

[nuQ]

I think I will go to Advance tonight and see if they can read off the exact code that is showing. As I said, the M appears to be running fine, and the CEL will clear each time, but then comes back on within 15-20 minutes, or after 2-3 start ups.... I'll post what they find

[nuQ]

Ok,,,had the exact code read tonight, and it is ----PO507-Idle Air Control System Revolutions Per Minute Higher Than Expected . Took it to Advance Auto to have the code read. I did a quick search on the net and it seems everyone that attempted to clean out the throttle body/plate by opening it manually had this pop up (and some posters above). If I had known, I would not have cleaned it that way, unfortunately, I did that method many times with my Q45 and had no issues, but I'm guessing it's not the same TB setup (or OBDII, since it's a 1990). I did see that I should probably do the manual re-setting again as it did not register when I tried it, but according to some of the responses I saw, it is IMPERATIVE that the timing be spot on (i.e, I will use a watch with a second hand).

I am still waiting for my extended warranty paperwork to come in the mail, that was transferrable from the previous owner. I believe it is a powertrain plus type warranty, so I wonder if the TB would be covered...?? Otherwise, any suggestions are appreciated, as I would like to do what I can before heading into the dealer. Thanks!

[atlM35]

Something free to try out first: Make sure all of the hoses and hose clamps are snug. A vacuum leak can also cause problems with the idle.

[nuQ]

Thanks atlM35....I did a quick 'look-see' and everything seemed to be ok....maybe I'll take apart all the hoses off the intake (like before) and re-attach everything, just to be 100% sure...

[The00Dustin]

Ok,,,had the exact code read tonight, and it is ----PO507-Idle Air Control System Revolutions Per Minute Higher Than Expected . Took it to Advance Auto to have the code read. I did a quick search on the net and it seems everyone that attempted to clean out the throttle body/plate by opening it manually had this pop up (and some posters above). If I had known, I would not have cleaned it that way, unfortunately, I did that method many times with my Q45 and had no issues, but I'm guessing it's not the same TB setup (or OBDII, since it's a 1990). I did see that I should probably do the manual re-setting again as it did not register when I tried it, but according to some of the responses I saw, it is IMPERATIVE that the timing be spot on (i.e, I will use a watch with a second hand).

I am still waiting for my extended warranty paperwork to come in the mail, that was transferrable from the previous owner. I believe it is a powertrain plus type warranty, so I wonder if the TB would be covered...?? Otherwise, any suggestions are appreciated, as I would like to do what I can before heading into the dealer. Thanks!

Ouch, I've seen several people have the problem where the opened the throttle body manually in this forum, but I thought that only applied to 06+ models, so I didn't bring it up. Since I still may be right, I'd definitely say try hte manual resetting again with a second-hand, but again, the steps you are using might be specifically for 06+, so if the resets don't happen, try searching the web for other methods for the 03-04, just in case they are out there somewhere. Beyond that, if you're still having trouble, hopefully the warranty covers it.

[nuQ]

Well, it looks like to the dealer I will have to go.... I pulled the battery overnight to see if it would clear and good for a few start ups then back on, and then did the full procedure (again) for clearing the CEL, and then resetting the accelerator and idle air, and yesterday seemed to be staying clear much longer than previous attempts. We drove to a wedding last night (after multiple start ups and the second day of the re-learn) which was around a 40 minute drive and was super happy to see the light still staying off. But...pulled up to the parking spot, put it in park, and presto, CEL back on. Noticed too that the idle was between 1000-1100 RPM's and I believe the CEL will respond if 200RPM's over factory setting? I did notice that the last time I did the full "driveway" reset of the ECU, the RPM's were around 700-800 RPM's, so it seems obvious that they are working their way back up, so just clearing and resetting will only work so long, before they creep up again.

Can the dealer reset this, or is this an indication that the throttle body (or something else) is broken just from the cleaning? I am waiting for the paperwork for my transferrable warranty to be sent. The previous owner purchased a Royal Administration Services, Inc (PVP) contract that I'm told is the "PVP Premier" package. This includes full powertrain plus electrical, so I'm hoping that the throttle body and related items might be included. Any thoughts would be appreciated.

[goldenchild7801]

nuQ did you find out what the problem was?

[nuQ]

Well, as far as the CEL, it will need to go into the dealer and have them reset it. I stopped in to talk to them about it, and they seemed to know just what to do, but would have to use the Infiniti software to reset to factory levels. For me, it's not a big deal since I live in a county that does not do emission testing, so inspection is not an issue. Plus, the RPM's are only 100-200 over factory and that's only when it's in PARK...not in drive/gear. When I have extra $$$ I will set up an appointment.

As for the tire pressure monitoring, I will also have them check that out while it's in.

[Costee]

NuQ since it's been a while that you had this high idle it ought to have normalized by now. Why don't you try unplugging the battery overnight and see how that turns out. If the issue remains, it just might be that you need a new TB/TPS.

[nuQ]

I have done the battery unplug over night,,,,and was good for about a half-hour, but went back when put in park. The Infiniti tech seemed very sure that it could be fixed at the dealer and without replacing parts....he said he has done many before. I did ask if the TB could have been harmed beyond reprogramming, and he said he highly doubted it...

Are you thinking I should do the battery unplug again?

[Costee]

Are you thinking I should do the battery unplug again?

No harm in trying.

[Double E]

I’m also interested in the solution. I cleaned mine and got the code ...but the driveway re-learn procedure fixed mine.

If I do mine again this year, I’ll want to know what the solution ended up being…

[idiom]

Any good mechanics in Fairfax area ? Need some help with 13 g37