Surge Idle and Misfire

[mfowler]

My car is a 1990 L98 hard top convertible. I've had the car about 6 months and only recently began having an issue with it. I noticed a few weeks ago that on cold idle the engine surges, sometimes it idles down to the point of almost stalling and then revs back up. Once it warms up it smooths out. Until this point it always idled very smooth. Anyway, although I thought it a little odd I didn't really pay a lot of attention to it. On the road it seemed to run great as usual. Skip forward to last week, I had it out and had driven about 50 miles with no problem. Stopped at a store for about 10 minutes and immediately when I cranked it up I knew something wasn't right. On the way home I realized I had a misfire (or at least seems like it) and on acceleration it actually bogs down. I haven't had a chance to check plugs, wires, etc. due to less than pleasant weather conditions.
Given the cold surge, and now a misfire, are they probably related? If so where should I start looking for the problem?

Thanks guys

 

[LLC5]

My car is a 1990 L98 hard top convertible. I've had the car about 6 months and only recently began having an issue with it. I noticed a few weeks ago that on cold idle the engine surges, sometimes it idles down to the point of almost stalling and then revs back up. Once it warms up it smooths out. Until this point it always idled very smooth. Anyway, although I thought it a little odd I didn't really pay a lot of attention to it. On the road it seemed to run great as usual. Skip forward to last week, I had it out and had driven about 50 miles with no problem. Stopped at a store for about 10 minutes and immediately when I cranked it up I knew something wasn't right. On the way home I realized I had a misfire (or at least seems like it) and on acceleration it actually bogs down. I haven't had a chance to check plugs, wires, etc. due to less than pleasant weather conditions.
Given the cold surge, and now a misfire, are they probably related? If so where should I start looking for the problem?

Thanks guys

Check your coolant level, and check for any stored codes. I think OBD1 can store some codes, if any are in there it may help tour diagnosis. Google your year, make and model, and "checking for OBD1 codes" and see what pops up. As much as I hate to admit it, sometimes youtube can actually be of help.