Engine bucking
 

Hi all,

My '98 Grand Cherokee just started bucking and shaking after I drive it a
few miles.

The problem is intermittent, but usually happens after it's warmed up, then
it shakes and bucks so much that it's nearly undrivable. I'll start it up
the next day, and it runs fine.

I've run dry-gas and STP cleaner through it, but I'm wondering what else
might be the issue.

The only other symptom is that it belches white exhaust long after it's
warmed up.

Thanks!

Bill

I would be checking for a failed head gasket.
Tom T