need fuel pump volume test specs (quarts per minute) 0n a 1997 firebird 3800 please
would shut off while driving in rain after dropping enough cylinders, I could see & hear wires arcing, & one tower on two different coils was not sparking. I pulled each coil & checked for 12 volts & a pulsing ground while spinning over & found that one coil was not getting a ground pulse. After doing a compression test & all cylinders passed & a scan w/ my maxi das ds708 found only random misfire codes, I replaced three coils, ignition module, ignition wires, spark plugs, fuel filter & changed the oil which was way, way over do. I felt confident that his skipping issue was would be cured, I ASSUMED...which is always improper. It is 85% better, & is not affected by moisture, but the car still skips like a little school girl. I have checked the secondary ignition and they all jump as far as the spark tester will open( past end of scale at 40,000 volts). No vacuum leaks, no smoke, no codes, & I can hear each injector ticking. The plugs look very dry and clean so I am thinking it's a lean misfire. The fuel pressure looks good, but the volume might be low at two quarts in one minute( from regulated system pressure check port on injector rail). Last item, it runs to cold so I guess the thermostat is stuck open. After running for twenty minutes the temperature needle has moved about five millimeters.
A stuck T-stat can mislead the ECM to try to run the engine rich. The O2 sensor will try to compensate but maybe it's out of range. The two issues together could cause misfires at speed. Its odd that the spark plugs are clean, but I would change the T-stat before doing anything else. Aside from that I would check the cam sensor and crank sensor (CPS) for proper voltage. Assuming the ECM is okay, either of those sensors can throw the spark timing off intermittently.
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