Well I have a vibration in my 302 at idle in park and it gets worse when I race the engine. I've done nothing to the engine or tranny,other than adding power disc brakes, so I added a vacuum hose. Other than that, nothing. Things I've done to try and correct it are New harmonic balance New tranny mount New motor mounts Oh yea, I did put a new starter on it to. I haven't checked the flywheel or the torque converter yet. If I have to go that far I'm going to be looking to put an AOD tranny in it. Any advice would be greatly appreciated.
It seems to be running smooth. It does it a good bit when I put it in gear and hold the brake. Then when I go back to park it smooths out.
Well, hopefuly it is only under a load and that could mean ignition system. Cap, rotor, wires etc.. I once had one that had a slight miss at idle, got worse as the RPMs increased under a load, smoothed out when let off. It was a burnt valve. I would start with the ignition system and check things off.
Here's an idea that costs nothing but time. Have the engine running in a dark dark location where you can stare at the engine for a few minutes. Concentrate on the spark plug wires and the ends, cap and plugs. After your eyes adjust to the darkness you should be able to see any sparks that are shorting. This is mostly for a kinda cheap way to get started before doing any actual testing. I would give it 5-10 minutes for the eyes to adjust to the darkness.
Well I did the test with the wires and didn't see anything arcing out, I even pull on the wires to see if one might be laying on my headers and causing it to short, nothing.
Alot of times you can still see the electricity running through the system. Did you see anything at all?
What I am trying to find is the miss and then start pulling the plug wires to see which cylinder it is.. Obviously you don't want to touch or pull any wires without the use of insulation like plug wire pullers.
