1996 Chevy Truck Engine Misfire

1996 CHEVROLET TRUCK
102,000 MILES • V8 • 2WD • AUTOMATIC
Avatar
RYNE33
  • MEMBER
  • 1 POST
The engine in my truck suddenly started to run very rough and misfire (while it was being driven). The check engine light came on immediately. By the time I got home at least one of the cat converters was very hot. I scanned the code and it came back P0300 random misfire, no other codes where set. it starts fine but at times I can smell raw fuel in the exhaust (due to the misfire problem????) The EGR valve looks fine and was not stuck open, It appears I am get a consistent spark to all cylinders. I have replaced the lower intake manifold a couple of years ago with all the standard tune up stuff (wires plugs etc) what would you reccomend I do (or where do I start??? Thanks.....Mark
Mar 11, 2008 at 10:11 PM
Advertisement
Avatar
2CARPRO JACK
  • CAR REPAIR CONTRIBUTOR
  • 11,533 POSTS
Sounds more like an injector problem than spark, those CPI engine were great for that. Need to find out which cyl has the problem. A scanner that can read "misfire data" will tell you or you can try squirting water on each exhaust port on the manifold to see which one is cold.You will most likely need a new injector.Try pulling the plugs to see if one is darker than the others
Mar 12, 2008 at 8:05 AM
Avatar
MASTERTECHTIM
  • CAR REPAIR CONTRIBUTOR
  • 4,750 POSTS
yes i agree. those injectors are so problematic that they have changed the design of it. when you buy a new cpi it will look different and be problem free. it seems like at 100k miles they go bad. it also comes with the fuel pressure regulator which is also very problematic. let us know if you need further assistance.
Mar 12, 2008 at 11:31 AM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.