well I was reading on here that sometimes when you pull the distributor and put it back in, there is the possibility that you could put it back in the wrong position. (off a tooth or two or more) I was under the impression that the distributor on GM motors would only fit in two positions. the right position. and 180 degrees off.

What is the correct answer? I had two different people tell me growing up that it was the latter but who knows. I just want to know the truth! thanks!

 

I think you can go a tooth or two off from the correct and 180 postitions but the computer relearns I believe so it makes up for being off by a tooth.

 

you can install the distributor and have it out of position, no matter how hard you try not to. as for these 2nd gen's, i've heard that you have to have a scan tool to recalibrate the timing after (a ASE mechanic friend of mine told me this when i did mine).
just remember, when you pull the distributor, take extra care to see where the rotor is pointing when it comes completely free of the engine. this'll ensure you reinstall it in the correct position, with the minimal amount of error.

 

You definitely get the distributor off by a tooth or more. Sometimes the oil drive will prohibit you from going too far off, but other times it can cause you troubles just getting it back to the proper position.

The PCM cannot make up the difference in being one tooth or more off. It will not be able to accurately time the motor for all situations if it is a tooth or more off. It just adds up to too much advance or retard for the PCM to handle.

As far as recalibrating the distributor, that is not for a distributor that is a tooth or more off. That would be for when you replace the CKP or CMP sensor. The CASE relearn (or crankshaft variation learn procedure) is done to recalibrate the PCM to the new sensors.

 

so you DON'T need to run the scan tool on the engine after pulling the distributor? i was told that it's the only was to properly check the timing. don't know why a timing light would be able to check it...........

 

You do not need to use a scan tool to check timing, but it comes in handy to check actual vs commanded timing if you need to verify things.

 

good to know Kyle. thanks.

 

So, what method would you use to ensure proper alignment when re-installing? Say...for a '95 W code? =P