I have a '90. Runs great for anywhere from 15 mins to 2 hrs. Tach will start jumping, feels like 2 or three cyls are dropping off or misfiring under load. Gets worse within a min or so. Once sits for hour or 2, restarts and runs fine. Anyone got idea?

 

age of your O2 sensor? if you don't know it might be time to replace it.

 

yup yup...that was my issue until replacement of the O2 sensor. all is well now

 

Heading to parts store as we speak. Thanx

 

Bought an O2 sensor and svc man. Nowhere in man is "O2" mentioned. By process of elim, fig'd it was Exh sensor. I'm sure I'll eventually find it on the car, but 8 days of rain has made it unpleasant to work on it.

 

bottom of the Y-pipe (before the cat) on the passenger side of the car