93 Century 3.3L No Start

[mcrbuick]

My Century will sometimes run for about 1 second when cold. After that engine just spins with no start attempt. Fuel pump powers up as expected. Shrader valved squirts fuel if pressed. Timing light on a plug wire shows spark getting to plugs. No trouble codes when checking diagnostic ports. Even tried starting with another battery running to insure plenty of amps.

Please help.

[richtazz]

I would start with the crank position sensor. Spark during engine cranking is controlled by the ECM, then switches to a signal from the CKPS after the engine starts. If the CKPS is bad, it will cause what you describe, and not always trip a CEL.

[mcrbuick]

Hi richtazz,

Thank you for the reply. I plan to get into some diagnostic exercises this weekend. No doubt, you know more about this than I. I thought that when a CKPS died it was all or nothing. I "checked that off" because of the fact that the motor would fire for a second when cold on occasion. Are you saying that this is behavior that you have witnessed with a bad CKPS? I did not know that the ECM fired the plugs during crank but that would explain why I got juice on the timing light. Is there anything I can do with an ohm meter or any other device to check the CKPS or must I go buy one, swap it and see if the new one works? Thanks again.