QuestionHi Roland,
this car is driving me nuts. The car runs perfect when I start it in the morning or anytime it is completely cooled off. As soon as the temperature gauge reaches the middle it starts running rough. The only code I got was "random misfiring", which I don't even get anymore. I have replaced the crank sensor, EGR and solenoid, Intake air temperature sensor, temperature sensor, MAP, spark plugs and wires. Before it started to do all that, the car would stall when hot and not start over until completely cooled. I have since corrected that after replacing the crank sensor. Now I don't know what else to do. The camshaft sensor is part of the distributor, which is expensive to replace. I don't want to replace it if it is not the problem. Please help
Thank you
AnswerHi Ricky,
You might do well to check the voltage pulse from the cam sensor when the engine is cold, and then again when the engine is hot and acting up. At least then that unknown will be removed as an issue. The distributor has a 6 pin plug (and a 2 pin plug) and you would measure the voltage between the tan/yellow on pin 4 and the black/light blue on pin 6 with the ignition switch in the run position but not running. You would put a socket wrench on the crankshaft pulley nut and turn the engine by hand and observe the voltage to pulse between 0.3 and 5.0 volts, I think once every full revolution, but in any case fairly slowly. You can access the wires with fine pins inserted either thru the insulation or where the wire enters the plug. See if the voltage pulses are the same when the engine is cold vs hot.
Other than the standard possibilities for multiple misfire that you haven't tried (coil which of course is part of the distributor, fuel filter/pump, pcm power grounds, water or contamination in fuel, injectors, restricted exhaust/catalytic converter, evap system) I don't have a specific suggestion. Keep trying for a code.
Let me know if you find something interesting or have a new code.
Roland
