Dave2001

I have a 2001 Chevy Silverado Z71 with a 5.3 litre engine. Recently it has been giving me problems. I had the transfer case replaced last week and the next day it stalled on me and would only crank but not start. I'm sure the two are not related but I thought I would give as much info as possible. I had it towed to the local garage and they determened that it was not getting fuel(fuel pump 2 years old) or spark. Sat in garage over night and it fired right up next morning. They put the computer on it and it said it was the Crankshaft Position Sensor. They didn't have one and it seemed to be working fine so I took it. Worked fine for a couple days then it stalled on me again and would only crank without starting. So back to the garage(saturday). On monday they tried it and it started and ran for ten minutes then died, same thing. I tried it again today(tues). started and ran for about ten minutes then dies. Will only crank and not start. It has an after market remote start/alarm.(there since I've owned truck). Phoned the installer and he doesn't think it is involved. My garage thinks it has to do with factory alarm. The security light on the dash flashes when door is open but it has done that sinced I've owned it(7 years). Closest GM dealership is 30 minutes away.
Does anyone have any idea of what this might be?
Sorry for being so long winded.
Thanks in advance.

recondrill

Next time it starts (after it dies) take it to autozone and get the PCM Scanned to see if there are any trouble codes. Your mechanic may just be throwing parts at it (and charging you) to see what works.

To check for spark, pull one plug wire at a time, connect an spare spark plug (use pliars) and hold it the grounding part of the plug near a ground on the truck. Have someone try to start the truck and check for spark. (there are some spark check devices you can buy, but if you don't do a lot of work yourself, may be a waste of money).

If all wires show spark, then the problem could be in the fuel pump or throttle body. Typically if there's a problem, the computer (PCM) will throw a code.

Good luck.

Dave2001

Thanks for your response. Will there be a code even though the engine light is not on? The closest scanner i can get to is 30 minutes away at a GM dealership. Live in a small town.

z71Girl

I would try the fuel pump/strainer and filter. They're known for going out on these models of trucks. I had a suburban which we put 3 into, and just put the second one into my truck. On the suburban, we had the strainer disintegrate and plug up the fuel pump at random internals. Sometimes it would run perfect, sometimes it wouldn't start. If this is the case, you can bang on the tank with a rubber mallet and it may unclog the pump. We had my suburban in and out of dealerships and independent shops both without any clear diagnosis before we found this problem.

Dave2001

Ok, does anyone know if the throttle body isn't receiving fuel because the fuel pump isn't working will there still be spark?

Starboy

Sure sounds like a Crankshaft Positioning Sensor to me. I've had two of them go bad, after showing exactly the same symptoms. I messed around with various codes and guesses, until I was stranded on the side of a New Mexico freeway for 4 hours, $275 tow bill, $375 repair bill. I'd seriously consider the CPS. They're not impossible to replace yourself, but you have to remove the crankshaft pulley, which requires a special pulling tool. I could have done it, but decided not to. The sensor was not expensive, I think like $30 at Autozone?

Dave2001

Yep Starboy you were right, Crankshaft Position Sensor. Just too bad I couldn't get it into the garage for over a week but whatever, it seems to be good now. Thanks for everyone's help.