Engine suddenly won't run above 2,500 RPM
 

I have a 2004 with 13,900 miles. Yesterday went to start it and it
struggled to start. The idle was fluctuating, all of the dash lights were on
and when I increadsed the throttle it ran rough at 2,500.
It even smelled a little funny when hot.

ECU bad?

Thanks

did you install anything on your car and did you try to start it again?

You can check the MAF sensor. If it is unplugged or damage it can cause similar symptoms. GL

Yea sounds like a maf problem

No, I have just strated and driven it every weekend since 2004.
Drove it last weekend. Then after sitting a week it just wont run above 2,500 rpm now.
The Check Engine soon light is on.

Get it scanned for codes and see what you get and then go from there

I recently came across this problem. But for me, everything was goin well till I ran over a little pothole then I noticed my car bogs out at 2k rpm feels almost like the rev limiter. So I take a look around and I find my oil is low and the leak is coming fro
my (looks like a valve cover). I'm now tryin to find out how to change my valve cover gasket. Does anyone know if backyard mechanic skills is enough skills to replace a valve cover gasket? Or might it be best for me to have a shop do it? By the way, where is this maf sensor located? I might want to scope that out cause it was after I hit the pothole when all my problems occured.

Thanks for the help :)

Disconnect the neg. cable on the battery. let sit for 2 min and reconnect. start the car and test. Mine did the same thing when I went through a car wash and drenched my air filter with water.

It almost sounds like a MAF sensor problem - but IIRC Safe Mode is 1500rpm max. Sounds like something else to me.

I know this is an old thread but wanted to convey what happened to me as it may be a help for others.

Came out of car wash w/ my '08 G35, car stalled, engine would barely start, really rough 500 rpm. Giving it gas didn't do anything. Opening the hood saw that water had definitely got in the engine bay. Buildup of leaves may have made it worse. I left the car for about 1 hour with the hood up. Got car to start but was in that limp mode & would only go 2500 rpms. After leaving it for another 2 hours, it was ok again. Also put some HEET in it to be sure. May save other folks from a tow & expensive mechanic visit.