WaarrEagle
Active Member
My long saga continues with my 2000 GTX DI. Had SES rebuild my motor after it blew. Got it back together and it was running pretty well. Put about 5 hours on it, multiple heat cycles, increased RPM's each time. But it had a mild, intermittent misfire. Interestingly, this misfire has been around for YEARS, well before the engine failed. It is most noticeable when the motor is under heavy load such as when coming onto plane. I suspected fuel pressure but put a gauge inline and it looks great. Solid 27 with key and 107 when running. The gauge does bounce around A LOT at lower RPM's but stabilizes at higher RPM's.
Today I finally got comfortable running WOT and wanted to see what it would run to test overall performance. I very briefly went WOT and saw 6860. Immediately after that the motor started running very rough, and even died at idle a couple times. I changed the spark plugs and it was no better. Pics of the plugs used during break in:
Air and fuel injectors were cleaned by FuelInjectorMan as part of the rebuild. No maint light. I just rented a compression gauge from O'Reilly and got 120/118 on a warm motor. Both numbers held solid after I stopped cranking. I know this is a tad low but I suspect the rental gauge may be off.
Given the misfire has a long history I am starting to suspect something electrical. No obvious issues inside the electrical box, but I may focus on the coils. Spark plug boots look and feel firm. Any other thoughts or suggestions? I am determined to get this thing running again!
Today I finally got comfortable running WOT and wanted to see what it would run to test overall performance. I very briefly went WOT and saw 6860. Immediately after that the motor started running very rough, and even died at idle a couple times. I changed the spark plugs and it was no better. Pics of the plugs used during break in:
Air and fuel injectors were cleaned by FuelInjectorMan as part of the rebuild. No maint light. I just rented a compression gauge from O'Reilly and got 120/118 on a warm motor. Both numbers held solid after I stopped cranking. I know this is a tad low but I suspect the rental gauge may be off.
Given the misfire has a long history I am starting to suspect something electrical. No obvious issues inside the electrical box, but I may focus on the coils. Spark plug boots look and feel firm. Any other thoughts or suggestions? I am determined to get this thing running again!