1994-2002 [Subscribe to Daily Digest] |
If the crankshaft position sensor fails, then the ECU does not even know if the engine is turning and can't do timing or ignition. And after the brief fuel pump run at ignition switch on, the fuel pump does not get any power unless the ECU sees the engine turning. So if there is no ignition and no power to the fuel pump, then the CPS must be suspected.
The CPS failures are typically when hot, but will run ok when cold.
When the engine is hot and will not start, you can check the resistance of the ignition coil primary and secondary windings. The yellow/grey wire should have power. If you get power on that wire, and the coil is not been grounded by the ECU, the other lead will be +ve as well. You can discon the green wire and then there should be +ve there as well. If the yellow/grey has power and the other terminal does not when the green wire is off, then the coil has an open circuit in the primary coil. The secondary coil resistance can be checked from the high voltage terminal to ground*. I would have the igntion off when going that!
* see comment in next para about secondary and ground, you might have to check to the green wire
And Haynes lists the pimary coil resistance as .52 to .76 ohms and the secondary as 7200 to 8200 ohms. Haynes shows the secondary coil's intermal 'ground' end tied to 12 -ve green wire in its wiring diagram. That makes secondary coil current go through the ECU which seems a bit odd to me.
If the cam shaft postion sensor goes, there is a CEL for that. For the CPS, the ECU is so clued out, a CEL typically not found. But with a pre ODB-II system, diagnostic codes are not very comprehensive.
Never hurts to check and reseat connectors.
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
![]() |
![]() |
![]() |
![]() |
![]() |