[MoneyMike02GT]

i need help or advice because my car is lagging bad. its a 2000 GT, whenever i get on the gas my car will stutter and will barely pick up from start off to around 5000-5500 rpm and then does the same thing after i switch gears. the car runs fine whenever i first start it up in the morning and take it down the road though. if i let it set overnight it runs fine for the first 5 minutes or so and then goes back to the stuttering. i cleaned my iac the day before this started happening. but i dont think i messed anything up because it ran fine for the next few hours. but after i let it set over the night it started acting up the next morning. so if any of you have heard of one doing this let me know something. thanks.

[vettekiller]

Did you say the problem occured after you took off the iac.If you did,did you replace the gasket and what did you clean it with?If you used carb cleaner that will cause it to stick.Also it possibly be o2 sensor.it sounds like it is happening whe the car goes into closed loop.Give me some more info and i can help you.

[MoneyMike02GT]

yeah it occured after i cleaned it. i was on another forum and a guy told me to use ether on it so thats what i used. and no i didnt replace the gasket because it was in good shape.

[MoneyMike02GT]

but sometimes after i run the car when i have to stop at a redlight or stop sign the car will almost quit when it goes to idle.

[MoneyMike02GT]

like i said before, i dunno what happens when the engine is cold but it runs perfect until about 3 or 4 minutes of running it and then it goes back to stuttering around and jerking when i get on the gas

[Skidmark]

Sounds like it has a lean mixture issue, try checking the MAF sensor and see if it needs cleaned. The computer while the engine is cold will run it rich until the sensor tells it that it's warm. So it's after this point that your having the problem. Could be something as simple as a vaccum leak. So i'd tend to start looking in that direction.

[97_4.6L_Stang]

plugs maybe. take it to a goodyear or somewhere with a good diagnostic tool. not the autozone thing. it will monitor the cylinders for missfire. and will monitor fuel to see if its lean

[White99stang]

i think it might be a 02 senser issue also, the question is when you actually floor it does it run fine cause thats when it goes into open loop and then when you are just driving normal it studders, cause mine is doing the same thing now and i need to get underthere and see if i burnt one of my 02 sensors on my headers.

[MoneyMike02GT]

even when i do floor mine it still stutters its like it isnt getting enough gas or something.

[MoneyMike02GT]

but my check engine light isnt on or anything

[White99stang]

i say check your plugs first, i am guessing you don't have a cowl hood, cause water would get it my engine bay when i rained and get down inside my cop and cause a misfire till it dried out

[vettekiller]

When the car is warm take the iac off and see if it is opening.You should not use ether to clean any parts on the intake they are coated and the ether strips it off.Use 3m throttle cleaner it cleans and lubricates and doesn't harm the coating.What happens is the carbon was cleaned off and when it heated up it crusted the iac closed enough to have a good idle when cold as it warms up it doesn't have enough air to breath.Replace the iac and gasket clean the intake side and throttle with 3m throttle cleaner only!

[DanishStallion]

how many miles?

if 50k+ and you never changed your coil pack.


then thats your most likely answer

[SWEET2KSTANG]

i have 85k with stock coils. i agree with the ether and coating issue, but another thing i would look at is the fuel filter.

[MoneyMike02GT]

ok i replaced my iac and gasket but the problem is still there. now my engine sounds really loud, louder than usual and my exhaust tone has changed drastically. my exhaust sounds crackling and my engine just gets really loud and shitty sounding. any ideas on what that could be?

[MoneyMike02GT]

and when i give it gas it sounds like it just revs really high and get really loud but my clutch isnt slipping or anything. i cant figure it out at all.

[Casper98GT]

Maybe you threw a rocker