Is that why my engine is idling a little rough and I have a p1345?

 

More importantly P1345 also indicates that the distributor is installed at least one tooth off. You'll want to clear the code and adjust the distro a tooth one way or the other and then start it again. If that doesn't work, clear the code and go the other way. You don't want to ignore it because you could end up damaging the engine because it is firing at the wrong time. I'm being a dumb-*** and completely forgetting the name for it. Right on the tip of my tongue. But yes it indicates that the cam and crank sensors aren't synched up.

I haven't tried it before, but me thinks that hooking up a timing light if you have one could indicate how far off the timing is. If it's more than I think 27 degrees, P1345 will set. The timing light could help you nail which way you need to move the distro on the first attempt. Once again...theory.

 

Thanks again, will play with it more tomorrow

 

"Detonation" was the word I was searching my noggin for in my previous post. In other words, while the crank is pushing the piston up, the spark plug fires too early and tries to force the piston down at the same time. So, I wouldn't run the engine more than trying to get the distributor in the right spot. Definitely don't drive it until you've rectified that code. Start with TDC again. Each tooth on the distributor = 27 degrees. Hence, P1345 sets when the timing is off by at least 27 degrees. Also note that you have about ~15 degrees of timing when the distributor is in position. But I'd bet dollars to doughnuts that the distributor is off at least one tooth in either direction so I would definitely go that route.

 

So did you get the P1345 solved?

 

I have not had a chance to mess with it, although I'm skeptical of the 'one tooth off' theory, wouldn't the blazer run rough throughout the rpm range if this were the case? Mine purrs like a kitten at just over idle and beyond. Starts right up too

 

Well it definitely will throw a P1345 if your a tooth off. Service manual even states really plainly. It basically states that if you install the distributor and it throws a P1345, it's not installed correctly. But, as I recently looked into, and posted for someone else (don't remember the thread) that isn't the only reason for P1345. It is a manufacturer specific code of "Crankshaft Position and Camshaft Position Correlation".

I can't answer your question whether it would run rough throughout the RPM range. I think there are some other factors that would make me say maybe not. Maybe someone else can weigh in on that.

 

Other things that can cause P1345:

1. Loose CMP sensor
2. Excessive free play in timing chain
3. Loose rotor
4. Loose hold down bolt
5. Poor electrical connection (could be worn wire insulation or a broken wire)

 

I do remember there being only one screw actually holding the cam sensor ... I'll try swapping that out with my other one

 

I Myself Have Been Fighting My 2000 Blazer. I Think I May Have Also Made The Same Mistake Except I Was Checking For Compression But Couldve Assumed The Minimal Pressure Opposed To The Much Higher Pressure Was The Right Stroke. Why Are All My Words Capitalized?