Hello, So I have bought my 82 vette a while back and when I first bought it, it ran decent, with a few things that needed to be done to it such as the fuel filter and a new fuel pump since it was lagging slightly. Well, the car has always had this problem, but it has gotten worse over the time I have owned it. It does this weird thing where, in high gear like 3rd or 4th and at about 900-1000 rpm, it shakes quite heavily and there is this vibration almost and is persistent in most city driving, and it is almost like the car is skipping a little bit or disengaging. It also does take a little longer to engage and sometimes feels as though the clutch is not engaging all the way. This problem however is not at low gears such as 1-2 or at least not noticeable and off the line it does awesome. At high rpm and at high speeds, the car runs awesome and gives me no problems. I had a friend of mine say it was the torque converter and another says it is the ignition system and I am still not sure.

Would anyone know if there is a way to test what it could be or if it is something I need to look at? I personally think it may be the distributor or something with the ignition system. But the trans being a 700r4, could have a need of new clutches.


If you need any more info, I can provide the best I can.


P.S. Also, I forgot to mention, When the car is in neutral and I press on the gas a little, it will climb steadily but then bog down back down to 14 then jump up to 16, all while keeping the same throttle position. I have replaced the sensor and did nothing to it. Also, it tends to try and stall when I press on the pedal and must quickly release and put on the brake. These may be unrelated issues but, they may tie in somehow.

 

Call me and we can talk about your issues. PM sent

 

Sound like maybe you have too much timing in the engine when loafing along with high vacuum. This is called "trailer hitching" where it seems like it's bucking back and forth.
The quick way to diagnose it is to warm the car up and then pull and plug the vacuum hose off the distributor, then take it for a drive to see if it still does it. If that fixes it, you need set up your timing and advance curve....we can guide you through that later.

OHH $hit....I see now you have an 82.....I'm not even sure they have vacuum advance...LOL

 

It is ALWAYS a good idea to 'run vacuum' on the car from idle to 4000 rpm. Then read the procedures on what the vac guage is telling you.
CFI DOES have possibilities of spurious vacuum leaks at the manifold. The MAP sensor is also vacuum operated.

On an 82...day one, hour one....go thru ALL THE HOSES FIRST, then the plugs and wires and eliminate that from your diagnosis.

Vacuum on a SBC...is like looking into your lover's eyes...always tells the TRUTH! lol

Good luck.
Unkahal

 

Ok, so I have a vacuum leak on one of the head lights, and my climite contral and i think also somewhere near the firewall on the driver side. would that cause that?

 

Vacuum leaks can make it act funky for sure, have you talked to Bucaneer, hes an expert with these
Not a fan of lugging an engine like that, in fact never use OD unless Im on the highway.Your 3-4 clutches will last longer