5.7 p1345

[96chev]

My 5.7 is throwing a p1345. I think it is the distributor gear. What should I do?

 

[lesterl]

Has the distributor been removed? Timing chain tight? How many miles? Could be the gear I suppose.......

 

[96chev]

I just got the truck it is a 96 Chevy pickup extended cab 5.7 and I don't really know much about it only code is running is that P 1345 I've been reading on some forums that the distributor gear gets worn out sometimes the reason for that if I'm not mistaken is that the timing chain may have slack for that reason the distributor will turn back and forth causing where I'm not really wanting to change the timing chain right now but I do want to get that code off because I'm getting a little miss or rumble about 30 45 miles an hour at Steady

 

[lesterl]

Sometimes a backyard or untrained mechanic pulls the distributor to do something or change the LIM gaskets/ Head gaskets/ etc and doesnt know it has to be set with a scantool, turn the dist counter clockwise a tad and see if the code comes back, I kept this up untill the code stayed gone, figured this should work for me for now untill I get the new engine built then I will pay to have it setup with the scantool (TechII or other aftermarket scanner with enhanced capabilites (higher dollar scantools))...

You could pull the dist cap off and press down on rotor and try turning back and forth, if it turns much it could be worn gear, if it wants to rise alot could be some worn thrust washers on the dist shaft above the gear.....

 

[96chev]

Ok. So got the code to come off and the truck is running fine. I did All spark plugs. wires cap and rotor and distributor gear is What was worn down.

 

[lesterl]

Nice, glad ya gotter going....

 

[sailormedic]

How do you isolate the Crank sensor from the Cam sensor? As far as which one to replace.

 

[96chev]

I'm not really sure what you're asking I had read that the P 1345 means that there is a offset between camshaft and the crankshaft I pulled the distributor and found that the gear at the bottom had been eaten up quite a bit it looked like an apple core. if you're not very experienced I would change out the cam sensor as well as the crank sensor if you still got no luck there then pull that distributor out and look at that gear when you mark the position of the distributor make sure you mark it on the valve cover the distributor cap and the rotor inside once you pull it make sure it goes back in the same way it could throw off the timing but you could hit it right on the Button. when I pulled the distributor on mine I did it the old school way I stuck a screwdriver in 2 cylinder number one and cranked the crankshaft until I pushed it all the way up then you position the rotor to cylinder number one and drop it in when you push it in it will be exactly at firewall and then what by the time it fits wear it supposed to be it will end up being at cylinder number 1. if that doesn't help you you can give me a call on my private number just write me a private message and I can give that to you

 

[sailormedic]

Thanx for the response 96. Sorry I was unclear. I've had my 99 Tahoe for about 4000 miles. It has 226,000 mles on it. It's had this hesitation since I've had it. Got me a code reader and it shows a P1345. I know it's a cam sensor,crank sensor issue, so i thought i start by replacing sensors. I was just wondering if there is a way to decide which one I should start with. Just had to put a new tranny in about 3 weeks ago. It's always run fine except for the hesitation.

 

[96chev]

I'm about 98 percent sure that you need a new distributor gear on the distributor it sounds to me exactly what was going wrong with mine and it's really not hard the car cost about 60 bucks is that something that you know how to do? if that's the original mileage for that truck then I am pretty sure you should have already replaced it about 30,000 miles ago so I would do that first let me know if that's not it and I hope you a little more

 

[lesterl]

You dont need to replace a sensor. Crank sensor bad and it wont run (fires the Coil basically a base timing as it is hard coded to the crank shaft.), with that code you have a possibility of a moved distributor (due to a LIM gasket / head gasket change / any other reason intake manifold would have been removed.) Or like 96 said the gear could be worn causing erratic timing from the cam sensor in reference to the crank sensor (timing offset will change as engine speed changes.)

So you probably ought to have someone who knows what to do pull the distributor, check the gear, and if that is good, then reinstall and run a CKP Relearn procedure.