stumbles

[timbo]

Ive a1991 festy 5 speed gl injected ....starts find idles but on accelation will go then stumble like keys off then resumes depending on the trottle position up at cruise with a stedy pedal it will go but a noticeable on off hesitation / help please!

[timbo]

? thanks for any help?

[1988redfordfestiva]

my 90 does this swapping out injector to see if that may be the issue tho gona try fitting some 89 pontiac gp ones in will let u know if they work

[Tim]

I had the same issue with a '93L I owned. Turned out to be the distributor.


-Tim

[JohnGunn]

You didn't give us any information about the history of how this problem first presented itself, but my normal advice when faced with "any" drivability problem is the same. Here it is.

Unless you have replaced the spark plugs since this problem first presented itself, do the following.
1. Buy a set of NGK V-Power plugs for around $10.
2. Carefully gap them to 0.044" using a wire gauge so that the resistance felt when drawing the gauge through the gap feels "exactly" the same for every plug. Take your time. Do not rush through this part. I call it going into my Zen mode.
3. Apply a thin coat of anti-seize compound to the threads of all plugs.
4. Torque the plugs into place one at a time.
5. After installing each new plug, start the car and notice any change in the performance of the car.
6. If replacing all the plugs does not cause any noticeable improvement in the drivability problem, take them out and save them for your next tune up.
7. If there is some improvement, but not a complete fix, leave the new plugs in.
8. Figure out the next most likely cause of your problem and address that.

I know you think your plugs are OK. Everyone does. Maybe you're right, and you will have wasted an hour or so of your time. But if you are wrong, (Welcome to the club.), and you move on to replacing expensive and little understood emission control modules you are committed to a path fraught with confusion, squandered money, wasted time, and certain disappointment. Don't make me tell you how I discovered this.

John Gunn
Coronado, CA

[miami man]

i had two festivas and both had corrosion in the coil wire tower of the distributer cap that caused problems.

[mattswabb]

Check your wire, cap and rotor.

[1988redfordfestiva]

well the pontiac injectors fit big difference in performance the engine idles perfect but next is plugs these have never been changed i got buy the same ones i did for the 88 the acdelco ones i've had better luck with these
there's champions in the 90 and they suck plus there alot of rust and debris over them plus i gotta do the wires but i saw a gapping of 0.044 my car says 0.045 ?

[miami man]

on a humid day one of my festivas stumbled and died about six houses from my house to i walk back home and got a distributer cap out of storage and put it on and it fired back up and ran smooth. i have started to carry extra wires and a cap in the trunk in case it happens again.