The ongoing struggle for 3.2 smoothness

Kurt S · Kurt S's Garage

Being close to my wit's end over the tendency of my car to run perfectly 90% of the time and practically leave me stranded due to bucking, backfiring, hesitation and inability to accelerate the other 10%, I've been scouring previous posts for possible answers. Whatever my problem is it is slowly getting worse.

Today the car decided out of the blue to not respond to the accelerator for a bit, as it has been in the habit of doing lately. I'd back out of the gas, coasting toward traffic or a stop light and when I'd ease back into the throttle, nothing, it was like the car was out of gas. Then with a lurch or a buck or two it would come to life and roar away. Then when I'd come to a stop and try to accelerate again the engine wouldn't even rev. Only judicious pumping of the accelerator (what that's doing I have no idea) would make the car backfire, buck some more and roar back to life.

This happened for about 5 miles today and I was almost forced to the side of the road many times. I was driving near one of the local shops and limped onto their street with a car I was sure would die at any second. Then, as luck would have it something suddenly fixed itself and the car ran flawlessly the rest of the way to their shop and all during the 10 minute test drive they took it for. Grrrrr.....

I've changed the CHT sensor and DME relay. The car had a major tune and service 5000 miles ago. After reading some posts and just for grins I discovered that my air flow meter's flapper valve is not sticking, that my throttle butterfly is not opening all the way and that my full throttle switch is opening at about 3/4 throttle.

Possible ideas suggested to me have been a coil that is going out or a bad fuel pump.

Those will be checked shortly but I just thought I'd re-check with you experts one more time to see if anyone has any further ideas.

This is driving me crazy.

Thanks

Kurt S

marcesq · marcesq's Garage

Kurt:

I hate to beat a dead horse but have you tryed unhooking the O2 connector??

Solved all of my rough running and bucking problems. Popped in a new O2 sensor and haven't looked back.

FWIW.

Kurt S · Kurt S's Garage

Thanks for the suggestion. No, I haven't unhooked it or tried a new one. Guess it wouldn't hurt to give it a try.

Kurt

jtratza · 10-02-2002, 07:29 PM

A lot of people seem to be suggesting the replacement of the DME relay when getting a problem like this. I thought the relay fails 100% and shouldn't be the cause of the stuttering or a intermitant problem.

I replaced mine and the problem continued until I and the local shop finally decided the only thing left was the connection on the mass flow sensor. By the way a few months later the DME relay did quite which was no big deal since I already had a spare.

jlex · jlex's Garage

Sounds like an identical problem I had back in the '70's with my 914. Was out in the middle of nowhere at night when the same problems arose. Popped open the hood to see if anything obvious was amiss... with engine at idle, it started up again & because of the dark, I was able to spot some electrical arcing from some kind of component to the tin work. A bit of electrical tape cured the problem, but I know I could never have found it if I hadn't been looking for it in the dark. Try looking for arcing at night. Good luck
regards,
jlex.

DJB · 10-03-2002, 04:36 AM

Have you checked the fuel filter or for crap in the fuel tank that may occassionally block pick up?

Tim L · 10-03-2002, 04:37 AM

I had a similar problem with a non p car it turned out to be the throttle position sensor. But I don't know if the 3.2 has one just a thought.

Tim

BGCarrera32 · 10-03-2002, 05:33 AM

Stupid question but...do you feel any odd feedback in the accelerator pedal? Do you push the pedal down...have a delay sometimes...then "whammo" the fuel comes on??

I noticed when underneath my '84 how "crude" the throttle linkage is and all the points it could get gummed up. Check the linkage near the transmisson fill bolt area, etc. I'm not sure how your 87 is setup but I am assuming it is not a cable secanrio...might as well start with the easy stuff here.

I would think if the bucking and backfiring is as violent as you describe, it wouldn't be a coil, unless it was a loose or shorting coil wire. A failed/weak coil in my opinion would feel more like the car is running on 1/2 the cylinders.

Good luck...!!!

Kurt S · Kurt S's Garage

Thanks for the suggestions, I'm still hangin in there, ain't givin up yet.

It's gotta be caused by something.

Kurt