My car wont rev above 2500 rpms. I tried the idle relearn procedure but it didnt seem to work. I now have disconnected the battery and Im letting it set so the engine can cool a bit so the engine fans dont activate. Anyone else have this problem?

When doing the relearn procedure, I unplug the TPS and my rpms bounce between 1200 and 1500. Is this normal? I know by doing this (supposedly) its supposed to reset the idle to 700-800 so this seems a little counter intuitive.

I started the day by replacing the IACV, then left it unplugged and drove to the Nissan dealership and had the replacement ECM reprogrammed. Without the IACV plugged in it seemingly ran fine with a Drive idle around 800 and a Neutral/Park idle around 1100. Drove to the local Home Depot to plug the IACV in after I noticed the 2500 rpm limit. When I first plugged it in the idle was excessively low, around 200 rpms and the engine would obviously die at this speed. I went into home depot to get some wire and started it again when I came back. Now it idles at the fore mentioned and doesnt die, but still doesnt rev above 2500 without falling on its face.

Any advice/ tips would be greatly appreciated.

 

plug your MAF back in

 

I never unplugged it to begin with :S

 

YOU may not have, but not revving past 2500 is CLASSIC MAF ...humor me.

 

^ Correct the engine is going into limp mode and almost always is the MAF or MAF wiring causing the issue.

http://forums.maxima.org/5th-generat...2500-rpms.html

Are there any current check engine light codes?

 

ROFL

I do understand the MAF problem but Ive never had any issues before today. I pulled the codes the other day and had the usual IACV and catalyst bank 1 and 2 codes but nothing along the lines of MAF. When I drove to the dealership I didnt have any problems either. I was driving well above 2500 rpm for sure. It wasnt until after the ecm reprogram that I noticed this problem, so this would lead me to lean towards something that needs to be reset.

 

I guess I can always "limp" my way to advance to be certain.

 

Car was running fine for the most part, then after the dealer it doesn't...why did you even go anywehre else, honestly? I think the dealer unplugged the MAF and forgot to plug it back in.

 

I was driving it easy on a crowded highway. I couldnt get enough speed to tell otherwise until I tried to do a U turn. Thats when I stopped and thought plugging the IACV back in would solve the problem. Somehow went from "operational" idle, to really low, back to "operational" on its own though. Maybe Im just and idiot.. I did look pretty closely at the MAF and it seems to be just as I'd left it before going to the dealership. Maybe my TPS is bad?

 

why did the thing leave the dealer with the TPS unplugged?

 

It's usually the MAF that won't let you pass 2500 rpms. Plug all the things back in or tell the dealership they need to plug all the connectors back in.

 

That was my mistake, I meant IACV. But to answer your quesiton, It drove fine on the way there without it, and it seemingly drove fine when I left.

I went to advance and pulled codes p0505 and p0403. I cleared them and the whole drive back the SES light didnt come back on.. Usually it comes on right away for the p0403. Ill drive it again later, to see if it comes on.

When it gets to 2500 it stutters as if the TB were fluttering between opened and closed, gaining a little bit of momentum then cutting out entirely, and shaking the engine pretty hard. I did manage to get it to 2700 without any problems though


Also I remembered the code I usually get is actually P0430 not P0403. So maybe this new code will point me in the right direction.

 

sounds like classic MAF though... take some CRC brand MAF cleaner and spray it, careful not to touch the element with your fingers

 

From what Ive read the 2001 does not have an EGR valve and the 2000 does. I guess I got a 2000 ECM and since I DONT HAVE AN EGR its throwing this code, possibly causing my problems. I guess maybe theres a possibility for something else, but it seems unlikely. I could either make an EGR emulator and figure out how to wire it up or try my old computer until I get a replacement. I KNOW my old ecu is toast because I could smell it when it happened. I'm sort of cornered on this one.


Im considering just sending my old computer off for repair. Even with all Ive spent, and would spend on that, it's still less than half of what it would cost at a dealership.

 

where did you get your replacement ECM? afaik they HAVE TO MATCH with your current vehicle. Regardless, the dealership should have noticed the replacement is not an exact match...

 

my car did the same exact thing when i had the 2001 max which burned out and i got a 2000 max ecu for replacement. Car did not go above 200 rpm which i figured was due to the maf, i replaced it but it did not fix the problem.

After pulling the codes p0403 for EGR, I realized that the 2001 maxima does not have the egr but the ecu was looking for it (since it was a 2000 ecu), by not finding the egr, i sent the car into limp mode.

I ended up getting a 2001 ecu that fixed all my problems but if you want to mess with it, i remember reading about a guy on here wiring a resistor in place of the egr to fool the computer.

G/L

 

I dont think the tech had ever worked with a computer on a 5th gen. He didnt even know where the computer was I had to explain it to him

I just bought it off ebay, I hadnt seen any issues with the egr when I researched using a used ecm. The most I saw were people concerned over cali/fed spec, tcs, adjustable suspension, etc.

 

Thats the guy I need to find lol. It seems almost more hassle free just to spend the 100 bucks to repair my old one..