Help! About 1 month ago, for no apparent reason, my 99 GT (manual trans) started shaking during acceleration for no apparent reason. When I give it some gas, the whole car tends to shake. It seems worse at lower RPM's. I thought it might be some bad gas, but it's been happening for over a month now. I took it to a mechanic and he had no clue what was wrong with it. It seems as though the engine is misfiring. This only happens when the engine's running cold. Once warmed up, it tends to go away.

I've tried changing the fuel filter, got a tune-up, and decarbonated the intakes and fuel injectors, but nothing has solved the problem. Anyone experienced anything like this before? Please let me know!


:bang:

 

a few people on the forum have had their ignition coil go bad. that wuld cause the engine to mis. try taking it to like advance auto and let them pull the trouble codes. hope this helps, oh yeah and welcome!

 

Yeah, I had a bad ignition coil on my car last month which caused a cylinder misfire. Is your check engine light on? If so, definitely get it checked. If it is a cylinder misfire, then it could very well be a bad ignition coil and a new one costs only about $40.00. However when I fixed mine it ran perfect, however now every once a while under WOT the car kind of shakes but not anywhere near as noticeably as before. Next weekend when I get my cold air intake in I am going to change, the oil, clean the maf, and change the fuel filter and see if that changes anything.

 

Thanks for the info. Only thing is, my engine light never came on. Will a place like autozone still be able to tell me which ignition coil is? Otherwise, I might just take it to a dealer.

 

Well without knowing which cylinder is misfiring you might have to take it somewhere else to find out which one it is. When I got my check engine light checked it said cylinder 6 misfire, so I knew immediately that that was which one it was. So your best bet would be to take it to a dealer. Good luck!

 

I hope this solves the problem. Spring is right around the corner and there's nothing I want more than to have my stang running smoothly.

Thanks for all the incite and suggestions! I'm taking my car to the dealer this week and have them replace an ignition coil.

 

Well my car has been doing the same thing for over a month now. It has been into Ford service 2 times already. Luckily it is still under warranty. So far they have replaced the feul pump and filter. Then they replaced coils # 1-5-6-8 and then replaced spark plugs #1-2-4-5. then replaced feul rail pressure sensor. Twice they have told me it was fixed and both times as I drive it off the lot, it is still driving horribly. So we will see how try #3 goes today. hopefully they can cough up a rental car so I can get to work.

 

too much torque

seriosuly though, where is the problem coming from? just the motor?

 

Swish,
Your post makes me nervous. Today, 3/7, I took the car to the dealer and got coils #1 and #5 replaced along with the spark plugs. I have not driven it around long enough yet to notice a difference. The fact that you replaced as much as you did and still have the problem makes me worried. I hope I do not have the same problem as mine is a 99GT, not under warrenty. If the problem persists, I'm going to make the dealer repair it at low cost as its already cost me a fortune. Once you finally find out what the problem was, please post here as it sounds like there's alot of Mustang owners that have this problem. :bang:

 

Well I got a call from my service advisor today. He said that the feul rail sensor was not working again and that they traced it back to the Pcm. so they have a new pcm on overnight and we will see tomorrow I guess. Maybe this time when they tell me its fixed, it might actually be fixed. Until then I will keep driving the beautiful Chevy aveo... :bang: that they are letting me use..I'll let ya know more tomorrow

 

yuck chevy aveo, they should pay u to drive that thing, lol

 

You say your car shakes during acceleration but you do not mention that the engine stumbles hesitates or backfires, does it ?
Could be the driveshaft universal joints are bad, I had a similar shaking problem during hard acceleration, had the joints replaced, problem solved!

 

The car would shake during acceleration because of the engine hesitating and misfiring. The engine seemed to 'surge'. The problem was most noticeable at lower RMP's in 4th and 5th gears. The dealer replaced ignition coils (and spark plugs) #1 and #5. It's only day 2, but I have not noticed my car shaking anymore. I'm not ready to declare victory just yet. Need a couple more weeks before I'm comfortable that the problem is solved.

 

mine shakes at braking tho. yeah at low speeds its worst... almost at a dead stop?? could it be that too??

 

It could possibly be your wheel bearings. I had mine replaced 3 weeks ago because they were making loud humming and road noises. My stang only had 57,000 miles on it. Perhaps you need new brakes?

 

i had the brakes done abot 15,000 miles ago. come to think of it... when you are goin about 30mph... windows down... you hear this like rotating squeak... high pitched... not incredibly loud. it does it at about idle when you are just cruising not accelerating. wheel bearing??? is that expensive? car has is daily driven V6 with 62k miles.