misfire problem

Hi everyone .My 98 jimmy started to have problems.Then it is at idle it start to vibrate like if sparkplug misfire.If I acclerate it will be gone for a while .Sometimes it does it ,sometimes not.I waited oter day till check engine light ,.Scaned for code it say p0300"random/multiple cylinder misfire detected" .I gess I have to mention new spurkplugs and spurk wires was installed.If anybody could help or have any idea whats wrong with it ?Thanks a lot

Check for spark to each plug with a cheap spark tester, if all are ok, check for a cracked cap, if ok, recheck plugs for a misgapped or cracked plug, BTW, did this happen before or after the plugs and wires. Of course you are sure the wires are on the right plugs!

Yes.I changed plugs and wires after it is started to do this.This is why I changed it .I had this truck for 5 years now and 110 k on it ,never had problems before.One of my buddes suggested to change computer .Don't know what to do?

I own a 96 and was getting P0300. I found a small hole (or melted area between the #1 and #2 runs on the underside of the distributor cap. It looked like there was a crossover in the spark between the two causing a misfire. I changed the cap and it fixed the problem. Another indication was a fouled #1 spark plug that had recently been changed.

Also search this site and the blazer site for P0300 code.