Crank sensor error codes.

[Mark61]

Hi folks

i posted about a week ago asking for advice about a coolant leak, and everyone was very helpful, for which I am very grateful.

i think (read hope, fingers etc crossed) that I have solved the leak by isolating the heater matrix, and have just read the error codes using a mate's OBD 2 reader expecting any codes to relate to overheating or coolant leaks, but was surprised to that all of them (4) all relate to the crankshaft position sensor. Apart from occasionally, (maybe once every 20 miles) it suddenly drops into limp mode, it's running fine, no misfires, no problems starting etc. Is it possible that what I'm assuming is limp mode is actually the crank sensor occasionally failing and just appearing like limp mode?

Any suggestions greatly appreciated.

[Digger]

It is possible that your cars software was never updated in the seven years between when it was built and Saab went out of business, or you could have a bad wire connection, but the most common cause of this problem is a failing crank sensor.

[Mark61]

Digger, thanks mate. Is there any way I can update the car software at this late stage.?

[Digger]

Odds are the magnet that is the body of the CPS has gotten weak from age and heat and the output signal isn't as strong as it needs to be to keep things running smooth.

If your car was Saab serviced through the warranty period, I would be surprised if it wasn't running with the latest update, but things are done differently in Europe than they are done here so it wouldn't hurt to check. To check or do programing you need to find someone with a Tech 2 and TIS software for security access.

The Tech 2 is a good tool to have if you don't have tons of money to spend on maintenance and you have a Saab. Purchasing my own Chinese clone Tech 2, TIS software and an older used Windows XP laptop to run it on, paid for itself when I did my own door lock and light switch program changes. Then it paid for itself several times over when I replaced my ECU with a good used one after it started flaking out.