rough idle ,vibration

[ddum8]

I have a 1991 s10 Blazer 4x4 with a 4.3 v6. My problem is that it has a very rough idle and the whole engine shakes. Also when I am driving it ,it has a vibration that I feel mainly at my feet. The vibration gets worse as it changes gears and is at it's worse in overdrive. It has a 700r4 automatic. Does anybody have any ideas.

Thanks, Ddum8
P.S. Go Jr.

[nex1]

Sounds like engine mount, my 97 saturn had the same exact problem, weird thing was I could put it in neutral at a stop light and vibration went away, I thought I had MAJOR tranny problems, dealer replaced the upper mount and drove like brand new!

[Rick Norwood]

I really doubt that the rough idle is being caused by a bad motor mount, although anything is possible. I would start with a basic tune-up, including spark plug wires, plugs, distributor cap and rotor, and check the timing. If that doesn't do it, let us know.

[nex1]

"whole engine shakes" um, that is what the engine mounts stops.

[Rick Norwood]

But what is causing the rough idle to start with? I have had broken motor mounts on many different vehicles and the engine purrs like a kitten. The way the broken mount was discovered was when the engine raises off the broken mount and the fan chews up the shroud. I am not saying that it isn't a possibility, I am saying that there are possibly multiple issues here.

[BlazerLT]

Originally Posted by ddum8

I have a 1991 s10 Blazer 4x4 with a 4.3 v6. My problem is that it has a very rough idle and the whole engine shakes. Also when I am driving it ,it has a vibration that I feel mainly at my feet. The vibration gets worse as it changes gears and is at it's worse in overdrive. It has a 700r4 automatic. Does anybody have any ideas.

Thanks, Ddum8
P.S. Go Jr.

Have you ever done a tuneup?

Fuel Filter
Air Filter
Plugs
Cap & Rotor
Wires

Any check engine lights?