Engine stalling
 

I have an 04 6spd coupe all stock. The other night I was driving home from work and I pulled out from a stop light and had absolutely no power. Pedal to the floor and the car was barely moving (acted like I was taking off in 6th gear). Did this for a few minutes and then all was fine again by time I reached the next stop light. It hasn't lost power like that since then, but as of the next day the engine stalls on a regular basis at idle. The frustrating thing is there is no codes or SES light.
So far I have tried the idle relearn and I did pull the MAF but it looked spot less so I didn't mess with cleaning it.
Also, the car was fueled up a few days before, and was almost empty. The car had been driven at least 100miles after fueling before any of this happened though.

Anyone have any ideas? They would be much appreciated :biggthumpup:

Might be the first signs of a camshaft position sensor or crankcase position sensor going out. Keep an eye on the car and if it happens again take it to an AutoZone or other auto parts store and have the OBDII port read. You might throw a code before you see the SES light come on.

Thanks for the response. I actually drove the car last night and kept checking for codes and at one point got the code P0175, running rich in bank 2, but I kept checking and the code was gone. Think they are related?

*UPDATE*

So today...
Cleaned the TB- No luck, actually made things worse.
Replaced the spark plugs-Made a big difference, but the car still wanted to stall.
Crawled under the car and gave the cats a few solid taps with a mallet-Stalling is gone but there is an occasionally sputter.
So I am assuming the cats are blocked. I dont have the equipment to do a pressure test, but it gives me a good excuse to replace them with some high flow ones as soon as I can come up with the $$$

One more thing after driving the car about 10miles after all of this I got the P0175 code again(still no SES light though). Maybe from the back up of exhaust gases giving the O2 sensors a false reading for high amounts of fuel in the exhaust?

You might be onto something with the cats. Here are other possible causes of the P0175 code:

- Faulty front heated oxygen sensor
- Ignition misfiring
- Faulty fuel injectors
- Exhaust gas leaks
- Incorrect fuel pressure
- Faulty Mass Air Flow (MAF) sensor


Do you run an oiled air filter? If so your MAF might be dirty, super easy to clean. If not you might have an issue in the fuel delivery system somewhere, but I wouldn't think your issue is that severe based on the progress you've made on it so far. Is it possible you switched a couple of coil packs when you replaced your plugs? Definitely something to check out I would think.

Let us know what the issue was if you find it.

The air filter is dry, but I did pull the MAF when it started since that seemed to be the common culprit. It looked brand new and no sign of dirt at all so I ignored it. The coil packs and plugs were pulled one at a time and replaced so no chance of mixing them up.
Wouldn't a majority of these issues trigger other codes and cause the SES light to turn on though? O2 sensor was my original guess, but I didn't have a code for it so I didn't think it could be the problem.

So here is an update. Its been a month now without any real stalling problems. Not sure what happened in the first place, but could have been a number of things. But regardless of what happened it seemed to stop after I got under there and gave the cats a couple hits. The idle does seems to bounce around slightly though. So I finally picked up a pair of fast intentions HFCS. The throttle response is notably improved, but nothing else seems to be drastically different. Its a little early to tell from only about 15mins of driving but seems like gas mileage may have improved also. The idle still bounces around slightly(between 700-775rpm). Sorry for those with similar problems that are coming to this thread looking for an answer. I still don't have one and probably won't.:dunno:

I was having something similar issue like 2 days ago, I had to try like 4 times to start the engine and it was on low rpms when engine was warm, just cleaning the throttle body fixed my problem. just my 2 cents.

Edit: I see that didn't fixed your problem, sorry buddy! keep looking for a fix.

hi I having the same problems, how to I clean and reset the MAF

Anybody's 2 cents is well appreciated :biggthumpup: Glad that fixed your problem!

I actually didn't clean mine since it didn't appear to need any cleaning, but from what i read you carefully remove the MAF sensor and spray it with MAF cleaner from any auto parts store and allow to dry. Then reinstall. Thats what I have read but search the forum a bit more and I am sure you can find a write up on it. I just can't seem to find it now, but heres one for a lexus should be pretty similar.

http://www.clublexus.com/forums/gs-s...and-gs430.html

Hope you find a solution!