MSP Help! Rough idle and loss of power

Do you think it would also have to do with my maf being on my cai and not off the intercooler. Pipe because I still have the stock one?
 
it shouldn't matter, mine is on my CAI, unless you put it on backwards, can you please clarify exactly what is the car doing again and when?
 
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The car fluctuates in idle between 5k - 6k when completely stopped and will drop lower sometimes almost to 1k. No vacumm leaks. The exhaust sounds like its sputterying in a way once warm and idling low. When I'm driving once car is completly warm it Acts like it can't accelerate untill you hit a certain rpm when the pedal is slammed. Its like something is closing before it should not sure but this doesn't happen when the car is cold. I'm cleaning my egr today after work to see if it helps at all.
 
The car fluctuates in idle between 5k - 6k when completely stopped and will drop lower sometimes almost to 1k. No vacumm leaks. The exhaust sounds like its sputterying in a way once warm and idling low. When I'm driving once car is completly warm it Acts like it can't accelerate untill you hit a certain rpm when the pedal is slammed. Its like something is closing before it should not sure but this doesn't happen when the car is cold. I'm cleaning my egr today after work to see if it helps at all.
i'm not understanding the between 4-6k, you mean 500 to 600 rpm? when the car is warm try unplugging your first oxygen sensor and see how it drives
 
it ran worse. and i cleaned the egr and it is still doing the same thing and idling rough its very frustrating because nothing is working. ive checked my hoses a million time and checked my filter on my cai and everything is fine. When my car idles rough the lights dim and such but i had the battery and alternator checked and they said they were both fine. im not sure what's wrong with my car at this point. its a mystery as to whats really wrong with this car.
 
Dammit , I was hoping we could find a solution to this. Can't you just go get ur car tuned at a performance shop and that should eliminate a problem right?
 
how warm is it out by you? mine feels doggy as hell when its warm out (just reached 75 today and felt sooo slow) nice and spunky when its cold out.

I also have felt the entirely fast car when its cold, and then nothin when it warms up, I tryed to reason it with open/closed loop... but i think it may have to do with the ignition mapping at various temps... although i have not confirmed this yet. (this is why I think some people luv the ecu reflash?)

I'd rather not just throw coils nd plugs at it like i have read many times... i did the resistance checks on my igniton, and only the #3 high tension lead was slightly out of spec.. w/ new plugs also.

Anyone know a lot about the stock ecu want to weigh in? like timing degrees at certain temps? etc. (IAT and ECT temps?)
 
that would make sense i think it has to do with the stock ecu not compensating for certain things. i feel like my car hesitates when spooling because the car is trying to bring it back down under the certain psi and its messing it up and hesitating but not sure. but i defiantly feel way more power when my car is cold. it was almost 80 today but my car was running alright until i stop and it wants to stall. still hesitated under acceleration whether its cold or hot.
 
do you own a mutimeter? if not get one from auto parts store for like 20 bucks and measure resistance of your coolant temperature sensor when car is full cold (let me know outside temp) and then measure it when car is full hot. let me know what you find i got a chart i can compare it too and see if its reading right, cause if its reading to low or high when car is actually fully warmed up it will cause havoc on everything other sensor in the car due to fuel/ignition maps.... let me know what you find.
 
Mustard, seems like you know the sensors pretty well, do the IAT and ECT sensors have the same resistance values per temp? aka BlknYellow should check when the car is cold: 1.) outside temp, 2) IAT resistance and 3) ECT resistance, 4) and also the ECT resistance once warmed up?

From my limited understanding, the ECT and IAT resistances should be very close before the car is turned on in the morning etc.
 
I didnt read through all of this so I'll just ask.

You said you changed your coils, but did you change and properly gap your spark plugs?
 
I also did not read the whole thread, but have you tried checking the intake manifold gasket??? Very common on the FS motor....the intake gasket cracks and creates a vacuum leak right at the cylinder head.

Get yourself a can of carb clean and spray where the intake mani meets the head. If your rough idle smooths out, replace your gasket :)
 
Yes gapping correct. I drove the car today and it was extremlu laggy today not accelerating untill after 4 rpms. Its really frustrating because the car spools but no power untill after 4k rpms. There's a lot of build up and its like something isn't opening.
 
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