View Full Version : Missfire 93 sts

10-18-03, 01:15 AM

Have a 93 STS getting a low rpm misfire 1000-2000rpm ......chugg chugg chugg hit the gas clears abit after 2000rpm then by 3000rpm she's flying.

Any ideas

10-18-03, 09:34 AM
Start with the obvious. Check codes, clean the throttle body bore, check for a vacuum leak, bad plug, plug wire, etc

10-22-03, 08:27 PM
Katshot is right on.
How long since it's been tuned? Change all the plugs ,probably the wires too, and check the vacuum hoses for a leak,then see how it runs.

10-23-03, 07:27 PM
did you clean your engine resently? i've seen some northstars do this before, after they were steam cleaned. Pull out the spark plug boots and see if there is water around the spark plugs, if so use an air gun to blow it out. its worth a shot:burn::burn:

Allante North *
10-23-03, 10:57 PM
epanightmare is right about the water. Happened to me a few months back and the air worked like a charm.

10-27-03, 01:37 PM
I hate to ask this question; are you using any coolant?

If so, and you do not see any leaks on the ground, you may have a headgasket leak.