A brain teaser for the Volvo pro

[userjg]

Volvo 2001 V70XC, owned since new

Here is the quick summary of symptoms:

- trouble starting when cold (38 - 45 deg F) - turns over fine but does not fire, can take 15-30 seconds of cranking
- the "engine system service urgent" message appears intermitently at start up
- when engine warning lite is on acceleration from a stop is sluggish *(2-3 sec delay)
- also intermittently at startup the "imobilizer..." message appears, engine idles fine but has no acceleration when transmission engaged, get rid of this by warming up at idle and then shutting down for 30 minutes

What I have done

- had codes read at indie, got some codes relates to TPS, but potentiator sweep shows it is fine
- checked all keys - all yield "immobilizer" problem
- cycled the door locks with the remote 5+ times - does not seem to affect "immobilizer" engage
- checker for idle hunting - don't see any obvious signs of ETM problems (replaced by dealer under warrenty at 50K, currently at 108K)

I have combed the various forums and I am stumped. Any ideas will be greatly appreciated.

Thanks

[JDS60R]

Let us know what codes you got. If you only tested the TPS on an analog meter you may be missing a dirty or interrupted signal that you could see on an oscilloscope or OBD code reader with graphing.

next in line is the wiring to the ECU. Need to know the code to a talk more on this.

Usually with a no fire condition I want to see how the cam and flywheel sensors are reading as well. Without proper timing inputs the car won't fire.

Graph the signals out on an oscilloscope or code reader and let us know.

[JDS60R]

Also - how did you test for spark?

[userjg]

I didn't get the codes only a comment that he saw four 'related' to the TPS, my mechanic did the check gratis

He did the potentiator sweed with the diagnostic sensor and did not see anything abnormal.

I havn't yet pulled a plug to test for spark, I will do so on the weekend.

Thanks