97 Blazer Ignition Problems

A few months ago my 97 Blazer with 130K started to lag (what seems like a misfire) under high loads before shift points, particularly from first into second. It would only shift I left up on the gas. After a few weeks of these intermitting symptoms, it wouldn't start so I changed the distributor cap and rotor and it ran great with none of the problems as before. Now after 3k miles the problems have resurfaced with the misfire while shifting and there is now a frequent misfire (approx 1 per sec) when going over 60 mph.

The plugs and wires are less than a year old and I changed the fuel filter with no luck. Could I have a faulty cap/rotor? Could the ignition coil be going?

Any ideas would be greatly appreciated.
Thanks!

BlazerJeff

Always possible especially if you used a cheapo like a Wells - had 2 of them go bad within 20k, one the rotor and the other internal multi fires in the plastic casting, so Delco or I use Standard Motor products also. Make sure you don't have vac leak somewhere usually over on drivers side underhood as hoses rot. Then always have to look at fuel pressure, possible sensors but should have a code (clean the MAF in air intake), ignition coil, etc so start with a good known cap/rotor to be use.