TPIguy87

Hey guys, I'm new to the forum but not new to third gens. Lately my 87 GTA has been experiencing some problems as follows:

1. On moderate to heavy acceleration it bucks and hesitates a little bit, some days it's worse than others and its just getting annoying, not sure what's wrong with it, tranny fluids are good and not black and don't smell burnt. Any ideas what my issue could be?

2. When I set cruise control at 60 mph it has a slight shudder, I was thinking maybe torque converter issues? But then I think it may directly relate to the hesitation on acceleration. If you guys have any ideas it would be greatly appreciated!

Thanks

Ozz1967

iTrader: (4)

Welcome to TGO!

Is your car thowing any codes?

When was the last time you had your wheels balanced?

When was the last time you changed your plugs/plug wires?

What was it doing before it started shaking? Were you working on it and then it started doing it or did it just start doing it on it's own?

TPIguy87

Haven't checked for codes yet, just had new tires put on it about 3 months ago but my problem start about a month ago. I haven't recently changed plugs or wires but i did notice a spot on my #5 plug wire that has a burn on it from sotting in the header, could that possibly be arcing on to the block? The only thing that confuses me is that the car sat for 2 weeks and ran fine for a day but the next day problems started again. I also thought it could have been a charging issue, but kind of ruled that out, im out of ideas as of right mow

Ozz1967

iTrader: (4)

If you have a missing cylinder due to a burnt plug wire, that would cause a shuddering that gets worse under load. I found this out when I melted my #8 cylider wire but couldn't see it because fo where it was melted at. It still looked connected. Change that wire and see if your symptions go away.

TPIguy87

I will try the plug wire and see if that will fix my issue. I haven't been able to find a place where I can just buy one plug wire I have to buy the whole set, so I talked to a guy at my local auto parts store and he told me to silicone the burn and wrap it in a heat resistant tape. Does this sound like a good idea? Or should I buy a cheap set of wires and replace the one to just to see if that's my issue? Here's a picture of my plug wire

ASE doc

Your problem sounds like typical ignition misfire under load. Plug wires cause this. The wire in the photo looks newer. How old are the plugs and wires? How about your cap and rotor. Also, look for any KV leak around the coil wire connection at the coil. Any place where high voltage can leak, like plug boots or the coil or dist cap, can cause the symptoms you're experiencing. A misfire will be more pronounced with the converter locked up, like when cruising.

TPIguy87

My plugs and wires haven't been replaced since I bought the car in June of this year, so I couldn't tell you how old they are, I did replace the cap and rotor last month and it didn't make any different in my issue, where are the coils located on these cars and when I find it what should I be looking for for a culprit?

TPIguy87

Ok guys, did new plugs and wires last night and it appears to have fixed my issue, there were burn marks on cylinder plug wires 4, and 6. Must have been arcing onto the block, all plugs fouled and very full of build up, runs better than when I bought it this summer, thanks for all the help!