hi, its a 00 blazer 4.3 , just wonderin where the crankshaft position sensor is

It is located on the passenger side of the front cover slightly behind the harmonic balancer. Looking at the front of the engine, it will be approximately at the 7 o'clock position.

If you are replacing this component, please be aware that a CKP variation learn proceedure will need to be completed. This allows the PCM to precisely calibrate the characteristics of the new sensor to that of the engine for accurate timing control.

thanks. could you tell me how to do the learn procedure?

here is what my scanner says.... PO339 -- crankshaft position sensor a ckt intermitant--- does that mean i havta replace it? on s10forums some people say they replaced it and didnt have to do the relearn part, others say they did.

ORIGINAL: agent305

here is what my scanner says.... PO339 -- crankshaft position sensor a ckt intermitant--- does that mean i havta replace it? on s10forums some people say they replaced it and didnt have to do the relearn part, others say they did.



Since it is intermitant it indicates either a bad wire or connector at the sensor or the PCM computer...it is not getting a steady signal...also check the cam postition sensor in the distributor since the computer needs both signals to sync the ignition pulses the DTC may not be totally accurate...but related...

ORIGINAL: agent305

thanks. could you tell me how to do the learn procedure?


Just unplug the positive conecctor of battery for ten minutes. That will reset the computer and everything will be allright. :)

ORIGINAL: cegimonl

ORIGINAL: agent305

thanks. could you tell me how to do the learn procedure?


Just unplug the positive conecctor of battery for ten minutes. That will reset the computer and everything will be allright. :)

Untrue. A CASE Relearn cannot be performed by simply unplugging the battery. This is a specific procedure that must be initiated via a Tech2 or equivalent scan tool and specific steps followed to complete the procedure.

I did the computer reset unplugging the battery and worked but anyway I will do the learn procedure that you said swartlkk (http://www.blazerforum.com/showProfile.asp?memid=667). Just a recommendation, that piece have a screw that does not have to be screw it to tight to avoid the crankshaft hit the sensor making the piece work failure and producing a weird sound.

It may work just fine, but you really will never know until you could potentially have a problem. A CASE learn will save you from spending a lot of money chasing problems later.