Garth S

I too am still leaning towards a failed mount either front or rear - which is allowing the exhaust system to beat up on the chassis: also, check all exhaust hangers. Be prepared to drop the bellhousing ....
If none of that pans out, look for issues that cause intermittent heart beats in the engine. For eg., pull & read the plugs - then replace if suspect. Look inside the coil tower for green crud - and clean the dist cap & rotor contacts.
When you stethoscope the drive line, also do each injector - each should make the same sound. Similarly, put a timing light on each wire if the vibration persists - and look for intermittent or weak ignition pulses
Going further out in left field, place a sensitive finger on relays XVI and XVII ( fuel injection and fuel pump) when the vibration occurs - you are looking for a weak relay 'chattering'' .....

tommytomaso

Well looks like i finaly may have found my vibration problem,
........It was the DAMM CAT!!!!
been working at getting the body issues fixed for paint and tinkering around with the exhaust when i desided to bash out the cats guts......one and a half hrs later and i come to find out a good size peice of cat material was stuck in the out pipe. (last year i changed out the cat with the 79' to see if that was my problem and thier was no change...but i took it off because it was way to rusted out) So it looks and feels that the cat was about 90% of the problem
and if i use that as the starting culprit: it shook under load snapping the air tube that clanked loudly and started to send vibrations threw the rest of the exhaust..causing the exhaust to fall off. Im sure i still have other things that may have allready been vibrating like TT and bad mounts but i did change the tranny mnts, and still have to change the MM... drivers side shows a tear but the motor dosnt rock much at all so id say thats not a big deal.
So long story made short....things look way beter.
And now that i own this shark (bought if from my nephue) all the beter.
And she should be getting painted in 2 weeks

morganabowen

I admire your intestinal fortitude, and sounds like you may have made lemonade out of lemons Pleeze post some pics when your done

tommytomaso

I love lemonade!!!!!!
removing the whole exhaust and replacing it with one from my parts car should of told me were the problem was...but it didnt.
still havnt taken it for a good ride....that shall be its true test, but i did take it around the block at 11pm last nite!!! no hood, no lens, covers just the fog lights : )

majhopper

For the Win...over one year ago.

What happened in between? Your nephew sold you the car, which I assume was still shaking, but you were getting it ready for paint?

We seem to be missing ACT III here.

animal8526

oh man man. loooong story. short version...

car was a-shaken still when I sold it to him. I could no longer put money into after buying the euro, but with the high amount of money I had already spent on it, the price was good even with an uncertain mechanical condition. the car has been being prepped for paint more or less for about a year, but my uncle got into it seriously after I sold him the car, and he found a good source to paint it for an awesome price.

see, the key thing in understanding all of this is the fact that it has always sorta been half his car anywho. garaged at his house in the winter, he took care of it while I was away, and he has done, or helped me do, alot of work on it. on top of buying it with me to begin with.

as far as the cat goes, he had reason for not thinking that was the issue... he had replaced the exhaust with the one off the parts car shortly after the issue came up. still had symptoms. we now believe that cat may have been fried too.

tommytomaso

Also....i did find that one MM on the drivers side is torn (not compressed) so knowing that i was pretty sure that was my big problem, and may still be a small contributer, so i decided to finish the body work and tackle the MM (still dredding) later. In doing prep work for working on the MM i decided to cut off the bolts that were rusted on the cat and put all new bolts on the exhaust so later it would be easy to remove. having the cat out and it was rattling i chose to bash out it inards, thats when i found a lrg peice that was blocking the exit!
So cleaned out the cat reinstaled and and WoW.......almost all the vibration gone...
Now the MM IS STILL AN ISSUE but i feel way beter now about the whole thing.

animal8526

MM shouldnt be that harsh. I can help... There are plenty of writeups, we just need to follow them. and remember, engine rocking when revved IS a good thing. if it doesnt rock, mounts are kaput.

majhopper

A nightmare scenario for those of us who like to systematically eliminate possible causes by cutting problems in half. Actually had this happen to me on a very expensive Heathkit audio amp when I worked as a bench tech there. Between one day and the next, my "test" capacitors went bad...

Glad you guys figured it out. Should be a very well gone over car by now.

tommytomaso

So true Maj, and sometimes its beter not to know ''all'' thats wrong with ones car.