P1345 Code -- Aaargh!

[rsmith8411]

Driving along...minding my own business...Service Engine Light comes on...the dreaded P1345. All of the P1345 forum discussions I have seen came after a distributor removal. I haven't had that. I did the intake manifold replacement 2 years ago and got this same code -- took it to the dealer and had them set the cam retard (?) and have had 2 years of happy driving till yesterday. Any ideas? I do not have any driveability issues - it runs fine. I just replaced the camshaft position sensor at $35. No help. When I restarted the engine the rpm jumped up pretty high then calmed down. I have read indications that this may be the crankshaft sensor gone bad. I'm tired of going on fishing expeditions replacing sensors. Any ideas?

1996 Vortec 5.7 L C3500

[rsmith8411]

It looks like I've had a lot of lookers but no takers. Good news -- I fixed it. It was the crankshaft position sensor. Replaced it - 5 minute job - and everything settled down and the check engine light cleared. Hope this helps someone else down the road.

[Riche]

Thanks for the info... This will probably help somebody down the road more than what tire size can fit on their truck.

B.T.W. Was there any diagnostics into your finding? or did you just take a swing at it?
I am asking b/c if there was a method of finding out it was the sensor. That would be a big help also...

Thanks again

[rsmith8411]

Of course the advice out there is everything from "there's no way it's a sensor" to "of course it's a sensor". The best advice came from a diagnostic flow chart produced by GM which I managed to weasel out of my local dealer's service dept. I also found it at Alldata (a membership is required). Here is a bootleg copy that I had to get out of a Google cache so it may not be there forever: http://64.233.187.104/search?q=cache.../dtc_p1345.htm

In the flowchart, step 2 asks about the high rpm and if affirmative then the response is to replace the crankshaft sensor. This is precisely what I did and it worked!!!!