Northstar Engines and System Technical Discussion Discussion, N* Carbon Fouling my plugs, Help !! in Cadillac Engine Technical Discussion; My 85,000 mile 1997 deville has been having a problem with misfiring. I changed the plugs(Bosch Platinum) when I got ...
My 85,000 mile 1997 deville has been having a problem with misfiring. I changed the plugs(Bosch Platinum) when I got the car in June as part the "I don't know what the old owner did or didn't do tuneup" along with wires,PCV Valve, clean EGR valve pintle & passages underneath(code 340`?). The car started misfiring so I pulled the plugs and they had ash on them with a coating of carbon. I put Autolite Dbl Platinums on 2 weeks ago (on recommendation from friend) due to misfiring and found ash on the plugs. Fast forward to today I put new Bosch Platinum +2's in and within 50 Miles I am,getting the same problem with misfiring !. I am going to pull the plugs tomorrow morning and see which cylinder is the culprit but my question is how can I clean the carbon out without spending $400 at the dealer for their procedure (TSB spray, leave for 2 hrs, vac out cylinders) ?
I have tried SeaFoam, dumping water in at 3000 rpm and niether seemed to work(I did both through the Brake Booster hose). I did shine a light through the plug hole and found the tops of the pistons looked like charred steak and the car has been using 1 quart of oil per 300-400 miles.
I am currently not the richest person in the world (between jobs) but I do need the car to get around and $400 is a deal breaker at the moment.
ANY help would be appreciated.
P.S. I beat the snot out of this car as per BBob and others to clean carbon but my front motor mount is shot (if anyonehas tips on replacing this doodad feel free to enlighten me) and don't really wan't to chance dropping the drivetrain on the highway