I recently found this forum and I hope someone can help with my problem.
I recently took my 1999 Pontiac Montana 3.4l to the mechanic and had a tuneup done. he put all brand new plugs and heat resistant wires, changed the air filter, as well as replacing an bad O2 sensor, the one before the cat.
The next day I had to take the car to Meineke because i still had no power and found that I had to replace a clogged catilytic convertor. after changing that out, we refired the van and the check engine light relit after about 1 minute. the code read a misfire on cylinder 6. after testing all the wires and plugs, the mechanic told me that it was a bad coil pack and that i should have that replaced immediately.
well, here i am after changing out the coil pack, wires, plugs, and cat..and still a misfire on cylinder 6
. the strange part is, when we were watching the diagnostics on the meter hooked to the van, the misfire stops when the rpms reach about 3200.
i have added injector cleaner thinking that number 6 injector was clogged, but that has done nothing.
Has this happened to you or someone you know? Can someone Please tell me something that we may be missing??? Thank you