Did you perform the relearn with a scan tool?
Did you clear all DTC's from memory?
Did the P0335 show up again?
Are there any DTC's in memory?
If so, what are they?
Did you check/adjust camshaft retard?
Speedometer acting erratic indicates there is an electrical problem somewhere, which if the pink wire circuit has a problem it could also set the P0335. (read post #9)

 

I know the 99 jimmys had ignition switch issues. Did they still have those problems in the 2001 blazers?

Im confused about the odometer bouncing around. Do you mean the Tach?

At this point, you have spent enough money on parts that didnt solve the problem that you probably could have taken it to the dealer. I hate it when that happens.

 

khristoph30 - I doubt the dealer fee would have been covered by the parts. The mark everything up a couple 100% and then tack on massive labor costs. I'm only into it a couple hundred bucks at this point.

 

Captain Hook - From what I've read you can't do the case relearn until the beast quits throwing codes. The blazer I'm working on continues to throw P0335. Timing is off way more than 10 degrees at anything above 2K RPM. I am going to explore the pink wire voltage, but I'm pretty sure the problem is going to end up to be a timing chain.

 

Sorry, I didnt mean the odometer, i meant the tach. Anyways, I think we have narrowed it down to the computer. I will be changing it out as soon as i can find one and then see if that fixes it.

 

Autozone has the PCM for $112 with exchange. It comes flashed with your VIN. If you buy one from a junk yard or out of another car you will have to pay someone to have it flashed.

 

True, You only have a couple hundred bucks into it. But you still have a broken truck, No solution, and youre still guessing. I would stop guessing what is wrong and throwing money at it and start gathering more information. You dont need a "fancy scan tool". I bought mine at walmart online for $150. it provides a live data scan feature. (Which is what I believe will give you the info you need.) Good luck!

 

I finally figured it out. I had read long ago that sometimes a shim is required when the CKP is replaced. I had read too much into peoples advice about looking for evidence that the reluctor wheel was contacting the sensor. When I had checked mine, it wasn't contacting. But today I decided what the heck, might as well throw a shim on the CKP and see what happens. Well, it WORKED!! No more pinging or missing. It's throwing a random P0300 now but I think that's because it needs a CASE relearn. Otherwise she runs super now. So glad I didn't go after the timing chain!!!

 

And for those who might be wondering.......the tach is totally steady now. No more jumping around. Other interesting points. Whilst I was playing around checking voltages I noted that if you pull the fuse for the crank sensor the motor won't even crank. That's a nice thing to know since I expect a blown fuse would cause the same thing. With the fuse in but the CKP unplugged the motor will crank but won't start. This confirms what I read somewhere that if the CKP isn't getting juice the motor won't start. When I measured the voltage at the CKP plug it was about 10.5 volts, not the 12v I expected. So, I would say if your motor starts but she's missing above 2,000 RPM and the tach is jumping around, throw a shim on the CKP and see what happens. It's cheap and takes less than 5 mins. Just saying...

 

Glad you got her going. At least you're in the ball park now. Performing the crankshaft position sensor relearn would have been the easy and correct fix.