Hey guys, the other day I bought my first blazer. Its a 97 4wd. It ran beautifully for the week up until yesterday when I was heading down to my unit. It started out with a slight lack of power, I thought the gas gauge was broken and I was running out of gas so I pulled into a gas station. I threw a few bucks into it to get me to my unit. I started it up and it seemed to run slightly better so I set off thinking the fuel filter just needed a second to refill. The issue got worse until it finally stalled less than a mile away from the gas station.

I got it towed back to my shop and when I got back there checked the codes and it was showing a crankshaft position sensor code. I replaced the sensor today and tried it to no avail. Thinking it could possibly the throttle position sensor I replaced that as well as the camshaft position sensor just to be safe. I tried starting it after replacing all the sensors and its still running like crap. I then deleted the codes and started it again to see if any will come up and in the 5 seconds the truck ran it threw out another crank sensor code. Tomorrow I'm going to return the new sensor and get another since it could be bad from the factory. Other than that does anyone have any other ideas?

 

I've never had to deal with it, so take this for what it's worth (not much!) but I've read on here before about having to do a "relearn" when the crank sensor is removed, replaced, etc.

There's several threads floating around on here, do a search, and see if any of your symptoms match what others have dealt with.

 

Yes, a relearn maybe necessary ...however it will still run!!! What needs to be done is to follow the flow charts for the code...... If it's throwing a code there's a reason.... Not just throw a sensor at it!!! there's most likely a problem with the wiring...........please do not just throw parts at it!!!! All u are doing is wasting money that could be used to properly fix it........there is a wealth of info on hear available!!! Please use it

 

Its an older truck so I figured the sensor could be bad so why not try that first, I really hate fixing wires lol. Its kinda funny because I also have a 2000 s10 that the crank sensor went on but that's the 2.2 so I couldn't steal the new sensor out of that to try it. I also know that sometime random other things like the starter and a bad battery could potentially throw that code. Guess its time to break out the multimeter and test the harness.

 

Sorry for bringing up my old thread but I got around to messing with the truck today. A friend of mine who was a mechanic for years and years mentioned it could be the fuel pump so I did a test and the fuel pump was bad. I replaced it over the weekend and tested it again and it builds proper pressure however...the truck still won't start and when it does it still runs terribly. I scanned the codes again and it came up with the cam sensor which I had already replaced. I'm going to test the wires later today but wanted to know if anyone else has any input of what it could be.

 

Vehicle will start and run with the cam sensor disconnected. Not the problem. Let us know when you are ready to stop throwing parts at it and actually diagnose the problem.

 

So how about the distributor has a ton of slop in it. I took the cap off to make sure I installed the can sensor correctly and I can lift up on the rotor and turn it a few degrees. The bolts that told the rotor on are tight.

 

Could have a bad distributor gear.