I'll "try" to make this short!

Installed LT headers, and am trying to start the car for the first time. I don't have any of the O2 sensors installed yet ... all plugged in, but just hanging under the car (haven't got O2 extensions yet).

Crank, crank, crank ... it won't start, but it's throwing a code - P0335, Crankshaft Position Sensor A Circuit Malfunciton. Where IS the crank sensor??? Why would that code set?

Anyone else ever run into this?? Or is it due to the fact that I don't have the O2's properly installed?? (I doubt it, but just wondering ... unless they need to be installed to be properly grounded or something? )

Help??

 

Unplug the O2's until you get extensions.

My guess would be something happened to the CPS wires during the header install. The crankshaft position sensor is on the bottom passenger side of the block, at the back. You need to remove the starter in order to get access to it.
Remember if you do need to replace the sensor you need to do a crank position sensor re-learn with a Tech 2 or some tuning software to make sure the timing is right.

 

Ok, I know which sensor you mean .

I wonder what the heck could have happened to it from doing the headers?! Before I started doing anything to the car, I disconnected the battery. The passenger's side header was the easiest to get in & out, unless I caught the wire for it when I was removing the factory manifold/cat?

Ok, well now that I know which sensor the check out, maybe that'll lead me in the right direction?? Otherwise, back to the drawing board ....

thx

 

did you try resetting the computer?

 

CHeck your fuse box in the engine compartment. When i installed my Headers somehow i blew that fuse also i didnt remove the plugs when the headers came out and went in. So I don't know how but i blew the engine fuse and cracked one of my plugs. Replaced the fuse and plugs all good

 

You don't happen to remember which fuse, do you? I still haven't gotten to the bottom of the problem yet (haven't exactly had/taken time) but I just got some information (gm service info) about diagnosing no start / CKP sensor faults, and part of it says to check ignition fuses under the hood, so maybe that's what it is??

I'll let ya know what I find out. Thanks for the advice!

 

well since its a little better weather out i'll run out and look. I think it was the a fused labeled engine. I'll look for sure in a sec

 

Finally had a chance last night to get back out in the garage. I tested all of the fuses under the hood, and they were all good.

Got back under the car again, and tested the voltage on each of the 3 wires going to the crank sensor ... only 1 of them registered ~12V, the other one would zero out completely, and the OTHER one was un-responsive (the multimeter wouldn't change it's ~.00x reading one way or another). This lead me to believe there must be a wiring problem.

Turns out, one of the 3 wires going into the PLUG itself was broken off INSIDE the plug?! I had to pop the pin connector out, and re-splice the wire into it, reassemble the plug ... and voila! The car started no problem .

Sounds not too bad with only headers and a Y-pipe on it!!