J
JayWinslow
Guest
My 82 Crossfire engine,electronics and exhaust are all original and I have owned the car since new. The car has about 70,000 miles on it and has recently began running rough and has progressively gotten worse to the point where it now backfires through the TBI's anytime you goose it (with no load in the driveway) and also has very mechanical sounding detentation pings at most any RPM.
The specifics of what has happened.
> The car began sounding and acting like it was missing after a drive home from a meet
> The next time I took the car out the missing began sooner but after the engine was completely warm
> I parked the car until I could spend time to solve the problem. I could start the car and later found that the fuel pump had gone bad. The car started. The miss was not as evident but now the car would backfire anytime you goosed it.
> I periodically tried to solve the problem and soon found that I had to replace the fuel pump again. I also replaced the pump relay and have not had a pump issue since.
> The car now has added a very mechanical sounding ping to the lower portion of the block and sometimes sounds like it comes from the front of the engine. I removed belts from the accessories and verified that the sound is coming from the block. At times the pinging fades but it could just be my hearing getting use to the noise.
> When the carb backfires, no flame is seen. The detentation appears to be contained within the intake manifold. The backfire sounds to be coming from the driver's side TBI butterfly plate when open.
Actions I have taken:
> Replaced the fuel pump and fuel pump relay (twice, as the pump has gone bad / been overdriven or something)
> Checked timing (checked roughly okay, not more than 2 degrees off suggested factory setting)
> Checked compression on all cylinders to see if I had a floating value. All cylinders checked out okay.
> Loosen one sparkplug wire at a time to see if I could isolate a cylinder (All appeared to negatively impact performance)
> Ran a computer control self diagnostic to see if any errors were highlighted - none noted, checked okay
> Observed TBI fuel spray. Appears to pulse nicely and in harmony between the two throttle bodies. Appears to appropriately increase pulse rate as RPM raised. Good cone shaped spray, no trickling
> Disconnected various vacuum lines (I have not check every single one but thus far nothing has surfaced as a problem)
> Checked the exhaust pulse - steady and consistent
What to do next? What could the problem(s) be? I don't want to go spending money hoping I find the problem?
Do you think I am dealing with a fuel, spark, ESC / Computer chip, slipped timing gear (1 tooth or so), a cad converter problem or something else?
Jay
The specifics of what has happened.
> The car began sounding and acting like it was missing after a drive home from a meet
> The next time I took the car out the missing began sooner but after the engine was completely warm
> I parked the car until I could spend time to solve the problem. I could start the car and later found that the fuel pump had gone bad. The car started. The miss was not as evident but now the car would backfire anytime you goosed it.
> I periodically tried to solve the problem and soon found that I had to replace the fuel pump again. I also replaced the pump relay and have not had a pump issue since.
> The car now has added a very mechanical sounding ping to the lower portion of the block and sometimes sounds like it comes from the front of the engine. I removed belts from the accessories and verified that the sound is coming from the block. At times the pinging fades but it could just be my hearing getting use to the noise.
> When the carb backfires, no flame is seen. The detentation appears to be contained within the intake manifold. The backfire sounds to be coming from the driver's side TBI butterfly plate when open.
Actions I have taken:
> Replaced the fuel pump and fuel pump relay (twice, as the pump has gone bad / been overdriven or something)
> Checked timing (checked roughly okay, not more than 2 degrees off suggested factory setting)
> Checked compression on all cylinders to see if I had a floating value. All cylinders checked out okay.
> Loosen one sparkplug wire at a time to see if I could isolate a cylinder (All appeared to negatively impact performance)
> Ran a computer control self diagnostic to see if any errors were highlighted - none noted, checked okay
> Observed TBI fuel spray. Appears to pulse nicely and in harmony between the two throttle bodies. Appears to appropriately increase pulse rate as RPM raised. Good cone shaped spray, no trickling
> Disconnected various vacuum lines (I have not check every single one but thus far nothing has surfaced as a problem)
> Checked the exhaust pulse - steady and consistent
What to do next? What could the problem(s) be? I don't want to go spending money hoping I find the problem?
Do you think I am dealing with a fuel, spark, ESC / Computer chip, slipped timing gear (1 tooth or so), a cad converter problem or something else?
Jay
