2008 Chevy trailblazer crank sensor problem

[Lamar]

After putting fuel in yesterday I immediately stared having problems. The truck wouldn't move over 5 mph. I pulled off the road and things got worse. Finally it wouldn't idle at all just die, then not even start. I replaced the fuel filter even though fuel seems to be coming through fine. I checked the fuel pressure at the engine, but there was pressure at the port. HELP

[ProTech]

If this problem started right after you put fuel in the vehicle, then I'd say you got got bad gas. This isn't too uncommon, we see multiple cases like this every year.

You're going to have to get it towed to a shop, so they can take a sample of the gas and look at it and/or test it. Usually a mechanic can tell right away if it's crap just by looking. If this is the case, you're going to need to fuel tank drained, the lines cleaned out, the filter replaced (again), and preferably a fuel injection cleaning too.

You would also want to double check the fuel pressure with an appropriate gauge just to make sure the pump hasn't gone out.

[Ronnie]

I replaced the motor in a 2008 Chevy trailblazer 4200 vortex and I put in a 2002 4200 vortex I found out the crank sensors aren't interchangeable the 2008 had a 3 wire crank sensor and the 2002 has a 2 wire crank sensor what can I do besides change cranks??? (SOMEONE PLEASE HELP)

[carriedi]

I don't have a clue. I repair or replace with things that are the same as the original. Don't do interchanges. You would need to check with a swap shop or a junk yard about interchanging engines from different years.

2002 to 2005 use one crank #88958866
2007 to 2007 use crank #89017797
2008 to 2009 use crank # 89060573
I have no idea what the differences are. Maybe someone else on this site knows and will chime in.

[Ronnie]

Thanks for the reply, I was told by a friend that I have to change the engine wiring harness and Ecu and use original crank sensor for that engine. Give you update after I do it today and let you know.

[DomM]

When I fill my tank with gas, sometimes the gauge works fine and sometimes it reads empty. When this happens, after about 30 miles it slowly starts to climb up and shows the correct amount of gas left. Normally when this happens the gauge goes to between 3/4 and full. Also, when I turn the key to start the engine, I must hold the key in the start position until it starts but when the gauge is working normally, I don't have to hold the key, it will automatically keep cranking until the engine starts. Not sure if this is connected to the fuel gauge problem. Should I replace the fuel pump or maybe just the sensor? I get a code of P0463

[carriedi]

year, make, model and engine will help diag

p0463 is for fuel level sensor circuit high voltage.

your ignition switch sends a signal to the pcm to start your engine. The pcm tells the starter relay to allow the starter to crank your engine over. Your ignition switch does not actually go to the starter. The computer controls the starter. The computer turns on the starter relay and watches the crank signal to get the engine running. Once you turn the ignition switch to start you can let go right away. the computer will keep the starter cranking until the engine starts or if it doesn't see all the right signals it will turn the starter off.