Thread: 96 5.7L Vortec P1345 code

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Finished a rebuilt long block installation on a 96 Chevy 1500 5.7L Vortec (Rebuilt long block with all the bolt on stuff from the old engine) BTW the old engine ran perfect but blew a head gasket.

Engine runs perfect (as far as I can tell). Starts instantly, purrs with no misses or noises of any kind. Super responsive to the foot feed. Put on about 200 miles with no issues. BUT...P1345 code keeps coming back after I clear it.
I confirmed
#1 piston top dead center (compression) , rotor points directly at the #1 plug wire.
Unplugged the Crank position sensor, engine would not start, plugged it back in, all OK
Confirmed firing order is correct with no wires crossed.

Timing light shows the timing mark is about an 1.5" before the timing notch on the plastic timing cover.
The code P1345 mentions the cam position sensor. Does this engine have a CMP sensor? Where is it?, I bolted everything back on this block and do not recall a sensor near the camshaft. Is it in the distributor?
Any thoughts on the code? As I said the engine runs smooth as can be with full power, no hesitation what so ever.

Thanks,
Kevin

think it is the distributor. I was at a mechanic shop and he was having a little trouble with one and said something about the cam sensor being in the distributor.

hmmm...makes sense. There are two connections on the distributor. Maybe one of them is the cam position sensor. No codes on when it was in the old engine.
I looked in a Chiltons for the timing procedure. There is no vacuum advance so I thought I had to pull a wire or something before I check with a light. The Chiltons says the engine timing is electronic and there is no adjustment
There is a unlabeled notch on the plastic timing chain cover. I don't know what the degree is. But the mark on the balancer is about 1.5" before the notch (that's about 20 degrees). Any thoughts on the timing being off? Do I need to pull an advance wire or something?
BTW moving the dist. either way about a 1/4" does not move the timing mark at all. Moving the dist. more then half an inch either way stalls the engine.
Thanks,
-Kevin

You need to hook up a scan tool to set the timing on this motor.
The cam sensor is in the distributor.

Originally Posted by randywrench

You need to hook up a scan tool to set the timing on this motor.
The cam sensor is in the distributor.

I do have a scan tool (is a code reader the same thing?)

Can you elaborate on the timing for this motor? Or reference any procedure? Any help would be greatly appreciated.

-Kevin

You need a scan tool that can read data not just a code reader.
I don't remember the procedure exactly I can get it tomorrow
at work.

Just to give and update on the P1345 code.

A GM dealer says any rebuilt Vortec needs to be hooked up to their diagnostic equipment and told to Re-Learn the rebuilt engine. Said it would take ten minutes but he'd have to charge a minimum 1/2 hour labor ($30). That's fine, I hope it works, I bring it in tomorrow.
I'd like to understand what's going on though. What's being taught? How does the computer know there is a new engine? The cam and crank are aligned by the dots on the gears. The crank position only goes on one way (slotted to the keyway on the crank) and the cam position sensor is in the distributor and that is dropped in exactly where the old one was. So what's being re-learned?

-Kevin

Follow up on the P1345 code.

Yep, that did it. 5 minutes on the scan tool, timing is perfect, no codes. Engine runs the same before and after the re learn. Perfect!

Thanks for everybody's help.

Kevin

code P1345 means the distributor is out of sync with the crankshaft.
the way you clear the code is to use a scan tool and monitor the
cam retard offset when the engine rpm is at about 1000, if the cam retard shows a value of 0 degrees plus or minus 2 degrees all is good! if not then you need to adjust the distributor.
you turn the distributor until you get 0 degrees cam retard while at 1000 rpms.