2001 Bonneville won't start
idkaac
03-12-2008, 10:35 PM
:banghead:
Last Thursday my Bonneville broke down while I was driving the gages acted like I was starting my car, then it died completly. When it tries to start it acts like its not getting fuel. We replaced the fuel filter and that wasnt it, fuel pressure is reading good. We had the codes checked and we are not getting any codes. We are getting an erratic spark. Is there any way to test the ignition module, camshaft position sensor, and crankshaft position sensor?
Any other ideas???
Last Thursday my Bonneville broke down while I was driving the gages acted like I was starting my car, then it died completly. When it tries to start it acts like its not getting fuel. We replaced the fuel filter and that wasnt it, fuel pressure is reading good. We had the codes checked and we are not getting any codes. We are getting an erratic spark. Is there any way to test the ignition module, camshaft position sensor, and crankshaft position sensor?
Any other ideas???
HotZ28
03-14-2008, 09:29 PM
AutoZone or Advance can check the ICM for you. Have them run it through several cycles to simulate engine heat.
If the crank sensor is failing due to heat soak, you will not have a CPS signal, or spark to the plugs until the sensor cools down! If you have a tachometer or scanner, check for engine rpm while trying to start. No rpm would indicate, no CPS signal.
If you prefer, you can test the crank sensor resistance while it is cool and it will probably be within the range of the spec. The spec on the crank sensor should read between 700 and 900 ohms. The problem most people run into when testing the sensor is, they usually test it at ambient temperature, not when it is hot.
When you have an intermittent CPS problem, the best solution is to remove the crank sensor, place it in a pan of hot water and hook up your DVOM to watch the sensor's resistance as it warms up. (Check it all the way up to a boil). If it is a bad sensor, resistance will increase, until it suddenly goes open. (That is the point where your car will either, refuse to start, or simply shut down)! Now, pour out the hot water and add cool water and conduct the test again. You can watch the resistance fall back into the normal operating range. This would explain the no start problem when the engine/sensor is hot.
Don't worry about the cam position sensor, it will not cause an engine to stall!
If the crank sensor is failing due to heat soak, you will not have a CPS signal, or spark to the plugs until the sensor cools down! If you have a tachometer or scanner, check for engine rpm while trying to start. No rpm would indicate, no CPS signal.
If you prefer, you can test the crank sensor resistance while it is cool and it will probably be within the range of the spec. The spec on the crank sensor should read between 700 and 900 ohms. The problem most people run into when testing the sensor is, they usually test it at ambient temperature, not when it is hot.
When you have an intermittent CPS problem, the best solution is to remove the crank sensor, place it in a pan of hot water and hook up your DVOM to watch the sensor's resistance as it warms up. (Check it all the way up to a boil). If it is a bad sensor, resistance will increase, until it suddenly goes open. (That is the point where your car will either, refuse to start, or simply shut down)! Now, pour out the hot water and add cool water and conduct the test again. You can watch the resistance fall back into the normal operating range. This would explain the no start problem when the engine/sensor is hot.
Don't worry about the cam position sensor, it will not cause an engine to stall!
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