For a couple weeks now i've been trying to figure out a problem with my 87' gn. I can't go past 2,000 rpm's without backfiring and flooding my engine. At firs i thought it was lack of fuel, i got new injectors, new fuel filter, new adjustable fuel regulator. none of wich solved the problem. Then i realized i was flooding when it would backfire, but the reason i thought it was lack of fuel is because the backfires feel like it does when you're running out of gas. So now i've come to the conclusion that my problem is spark. I got new plugs, new wires, still the problem continues, so i tried my friends ignition module and coil pack wich are in great condition on my car, still the problem continues. If anyone has any idea what this problem could be please let me know, and if you need any further information on my car, feel free to email me. Thanks
-Wayne
Have you got any scantool readings when it happens?
My guess is one of the following:
- fuel pressure not keeping up (regulator)
- MAF bad (does it pass the tap test?)
- Over boost condition for the octane (try some good gas... 100+ octane ... and see if it gets better)
- Cracked vacuum lines to the boost soleniod/wastegate causing overboost
- Too much timing due to crank sensor failing or interrupter bent