hey hows it going i was reading this post to see if it would relate to my prob it all started when i put on a new intake manifold, it all ready had the bbk cai and 75mm pleum. but when i am diving the car would act like it was running out of gas so i would push on the gas and nothing would happen i could hear the intak suck but on go power and the car is still running so i pull over and idle for a bit push on the gas the motor would rap up so i put in to gear the car would stumble like out of gas but then it takes of like nothing had happend. so i changed the fuel filter out and cleand the maf senser and still does it. so what do u guys think. 02 gt with 45k
Its your cops or injectors. Is not your IAC but if you clean it you will get a better start when cold or warm. Check all main connections to make sure they are all the way in. If your car does not have cats in the exhaust it will seem like the IAC is bad but may not be. Oh check if each COIL has sparks. You can do that just by taking it of the plug one at a time turn the car on and you will here that spark. Don't tuch that spark it hurts lol...
hey i have a '98 GT convertible and it's idleing too high. It normally idles at about 700rpms but now sometimes it idles at about 1000 or 1050. I replaced the IAC valve, nothing. I put in some fuel system cleaner thinking maybe the injectors were clogged and it worked for about half a day. If i rev the engine it'll rev high and take a while to come back down. it's really starting to bug the crap outta me. any ideas?
Check your pvc valve on the passenger side of the head. Maybe be you left some thing wrong. Is where it intakes all the fumes from the inside of the ingine to burn it. Some thing might be open and is getting more air. Check lines or replace pvc valve. I usually have customized that part on my 00 gt I have and oppening that I can open when I want to race. It acts and souns like a hot rod engine and it gives me about .2 to .4 seconds faster at the 1/4 mile its a quick trick. Its like putting a bigger air mass meter.
i've been reading through this thread and my car has some of these symptoms:
i just got it out last week (it was stored all winter and fall - about 6 months) i ran it a few times in between and i put stabilizer in it when i first put it away. It runs perfectly fine when i start up and run it for a while, but once it gets warmed up it seems to have an idling problem. If im stopped for any reason(light, parked, etc) the idle likes to jog up and down. Does this sound like IAC ?? could i just unplug the neg terminal for 20 mins ?
There should be a hose behind the plemun the intake part. That could be torn check it it makes the rpm to dance. Is kind of hard to see it. If not check all hoses among vacum.
nice thread. I have an'01 GT with 95K miles with a bad idle/stumble, like its about to die when it's in drive sometimes. I have cleaned the throttle body, MAF wires, K & N filter, and IAC. The problems were better for a while but have started up again. I am about to reset the base idle and set the TPS voltage. I have not changed the plugs or wires which may very well be the problem. Does anyone know anything I may be missing. I miss the old performance of my car. everything is still stock by the way.
My 2000 GT started having trouble starting 2 summers ago, it would turn over just fine and would rev up to about 1,200 rpm as usual, but then it would quickly die right back down past the normal idle of 500- 600 rpm and stall out unless I kept it alive with some throttle. Half the time this would work and the stang would finally regulate itself in a minute or two, and half the time it would not stay running for anything. A good friend of mine suggested cleaning out the throttle body with throttle body cleaner, as a few of you on this tread have said and it worked fine. ( By the way, there was quite a bit a build up in the throttle body, and there is every time I clean it ) I have had to repeat this process every 2 - 6 months to keep the stang starting the way it should. I agree that this is an effective band-aid treatment, and other wise the car runs wonderfully, but I am wondering why myself and so many other mustang owners face this problem? Also I am wondering if anyone could tell me if it would be worth me replacing the IAC? And if I replace the IAC, would I still have to clean out the throttle body, sometimes as frequently as every two months?
( By the way, I keep the MAF sensor clean, so I doubt that is the problem, but I am open to any help I can get! )
Any suggestions would be greatly appreciated!
My only suggestion would be this - if you are having trouble with Mustang stalling out shortly starting, try cleaning the throttle body with throttle body cleaner, wipe it out well, then start your Mustang and drive it for 10 - 15 mins to get rid of excess cleaner!
warsumm, not to sound like a smarty pants, but I don't think you have spark plug wires, if those are the wires you are talking about. Your coil should sit/ cover and connect to your plug. That is, if you have the stock motor in your 2001 GT. Is your check engine light on? If it is, that would allow you to get some codes from a code reader, and that would tell you if you have a cylinder misfire : ie: a faulty sparkplug and or coil.
I really feel your pain bro, I kinda have the same issue with the rough idle, and cleaning my MAF sensor and Throttle Body ( use throttle body cleaner, and get all around and behind the butterfly valve! ) usually gets me right back on the road, with a smooth idle.
Except for right now, as I have a misfire in the #8 cylinder, so I am going to change the plugs in the morning, and hopefully I will be running smoothly by lunch time tomorrow. ( knock on wood )
Good Luck to Everyone with these idle issues.
Happy Holidays to All
LOL! yeah, I didn't think there were wires there just the plugs. Ive just started to DIY stuff on my '01 due to the rough idle and slower-than-used-to-be performance. No check engine light currently, although after a rain sometimes, it'll have a terrible stumble/idle, at which point the light will go on, and at which point I will disconnect the neg- from the battery to reset and engine light goes off. I initially cleaned the MAF, throttle body, K & N filter and IAC, and like i said, everything was fine, for a week or so, not perfect, it still lacked its old performance. But, since that time, I have re-cleaned everything to not much avail. It has never stalled but sometimes sounds like its going to once I initially give it some gas, especially if Im trying to get traction on a bit of snow or ice. Its just frustrating not knowing exactly what the problem is and I'm not bringing it to a shop or especially a dealer because i will get robbed. A high-performance step-by-step tune-up is next on the list. If anyone has a link to a good one(with images and instructions) that would be very helpful to myself as well as to the majority of people experiencing the same problems. I found one decent one, but it didnt have pics and some of the terms and steps were obscure to me. ok thats it for now.
Hey warsumm,
Have you by chance, taken your car by an autoparts store that will hook up a code reader to your ride, or a store that will let you use their "code reader" in the parking lot? I am pretty sure that if your check engine light is on it will give an error code to the "code reader" . If you can get your ride by a parts store when your CEL is on, and scan it with the code reader, it may help you pinpoint the problem. In my case mentioned in the previous reply to yours, it helped me to pinpoint the misfire in my #8
cylinder, which I fixed 2 days ago with a simple spark plug change.
I just thought I would ask.
Also, if the parts store you go to will not check your ride for codes, but will let you take the code reader to the parking lot to use it, take them up on it. It is easy to do yourself. The code reader plugs into the wire harness under the dash, towards the middle of the car with nothing plugged into it. It is the same harness that most states plug into when testing your emissions.
hey, thanks man. yeah. it rode terribly yesterday, stepping on the gas all the way and watching the rpms slooooowwwllly move up, felt like there was no gas in the car. But yeah, ive been waiting for the check engine light to go back on, ironically, so I can get it tested.It was flashing yesterday but never leveled off and stayed on. Once it does though, I plan on taking it by a Murray's and getting it tested. by the way, any ideas on how to actually trip the engine light to come on? Thanks for all your help, hef,and everyone else. i will def keep everyone updated.
ok, well I took the plug out from the iac in order to reset the base idle and the car wont even turn over. Is this the correct plug?The only other one i see is the plug going into the TPS. thanks for any help!
well, the check engine light went on, i read it at the auto parts store as "idle air circuit", bought a new IAC for 50 bucks, installed it , and there is absolutely no change to the performance/idle. It almost dies at idle which is something it hasnt done in weeks past. The acceleration is in the toilet, I feel like Im driving a freakin' go-cart except the go-cart is in better shape than my stang. back to the drawing board I guess.
Ok, well, I am almost 100% positive , although i havent cleaned/replaced it yet, that my problem is the EGR valve. I do have a "pinging" sound when I accelerate, acceleration is very very poor and it has an awful idle, almost to the point of stalling. I will clean it and replace at least the gasket first thing in the morning and give updates. I hope this works!!!!!
umm, well I removed the 2 bolts that attach the egr to the throttle body and took off the small hose located on top of the egr, but the valve is still connected to a very large pipe and Im unsure how to remove the egr valve from this pipe. I have 2001 GT if anyone know how to take the valve off this last part i would appreciate it. I dont want to break the pipe or anything. thanks for any help!!
well, cleaned the EGR valve, had a lot of crap in it, yet there is no change in the performance. Im probably gonna have to take it in as Im running out of options.
don' waste your time 
