BP Mx-3 missing on acceleration

johnboi85 · Post by **johnboi85** » February 18th, 2005, 8:04 pm

The problem i'm having is when i accelerate it starts to miss. it only does it sometimes but enough to annow the hell out of me. when i turn on the A/C the missing get's worse and the car starts to buck. what is going On? thanks guys.

matt_fulghum · Post by **matt_fulghum** » February 19th, 2005, 7:04 pm

bad coil or distributor? weak wires? if it's only doing it at high rpms, those are likely causes, especially if they're old (120k miles or more)

Other than that, if it's just at WOT, regardless of rpm, maybe a bad ECU? I dunno....

Tunes67 · Post by **Tunes67** » February 20th, 2005, 3:25 am

Check for excessive play in your distributor shaft. Also make sure the rotor is fully seated onto the end of the shaft. Make sure all of your plug wires are fully connected (they like to pop off the distributor cap if they didnt get fully seated) The reason this is getting worse when you turn on your A/C is because you are increasing the load on your engine when you engage the A/C. The question is.. is it electrical load or is it the extra load the compressor adds to the fan belt when its activated. First thing I would do would be to eliminate the electrical possibilities.. which include the steps above and maybe replacing or upgrading your ground cables as well. A trick I like to use for checking spark in each plug wire (without getting your azz shocked off) is to clip a inductive timing light over each plug wire (one at a time) rev the engine and see which wire(s) cause the timing light to fire inconsistantly. At the very least this could help you determine which plug wire and or spark plug is having the issue. Assuming that your misfiring can occur when the engine is not under load from the transmission. Just a few ideas..

Tunes67