P1345 With new distributor

[Fragment]

I’m having a hell of a time with a distributor on a GM crate L31 that I dropped in last week.

I’ve stabbed the distributor in at least 20 times and have verified TDC and followed the instructions I’ve found on this forum as well as the service manual... but I consistently have about +30 CKP retard and consequently get the p01345 code and poor running.

I tried a tooth advanced and retarded from the position I’m coming up with as TDC 1, but in both directions I get a no start condition with backfiring.

The distributor is a Chinese special I’m sure... listed as “AcPulse” on Amazon. But it had pretty good reviews.

I put in Delphi crank and cam sensors and threw the Chinese one that came from the distributor in the trash before ever running it.

My question to you guys is, have you ever seen a distributor bad out of the box? I’m wondering if that’s the situation, or if that situation is even possible with the gear being off clocked by 30deg.

I notice as well that the bracket that came with the Chinese distributor will not allow for final timing rotation as the stock one would, so I ordered an acdelco hold down clamp that should be here later this week. But I can’t even get close enough to achieve final adjustment so it seems to me that the initial problem is bigger than that clamp.

Other than that I’m at a loss as to what could be wrong.
Any ideas?
Cheers!

 

[geeeee89]

I think you need to set the Cam retard offset, done by twisting the distributor. I changed my intake manifold gaskets the other week and had the same code, but mine would run. You have to have a scan tool to do it, I had a bluetooth obd scanner and using the dash command app, with the CMP PID purchased separately. If yours won't start you may have to loosen the distributor hold down and twist the distributor a little bit one way or the other before it starts, then twist a little more to fine tune it after it's running. Very minor adjustments too, if you do it too much it will die.

Once I got this set right at 0 degrees, I tightened the hold down and cleared the code and she runs perfectly again.

Look at this thread and do exactly what the guy "bronyaur" said.

https://www.gm-trucks.com/forums/topic/211999-misfire-issues-with-98-yukon

Basically you twist it a little bit, turn the throttle linkage to increase RPM above 1000, then let off, then read your CMP reading on the scanner. The cam retard offset needs to be as close to 0 as possible. Mine was at like 18 to start with after reinstalling the distributor. Keep making small adjustments and raise the RPM above 1000 each time to reset it and get a new reading. Once it's close to 0 as you can get it, carefully tighten the hold down bracket, raise the RPM again check the reading again to make sure it didn't move on you, then you should be good.

Helps if you have one of the bent distributor wrenches that goes on your ratchet. I think I got mine at auto zone

 

[Fragment]

I think you need to set the Cam retard offset, done by twisting the distributor. I changed my intake manifold gaskets the other week and had the same code, but mine would run. You have to have a scan tool to do it, I had a bluetooth obd scanner and using the dash command app, with the CMP PID purchased separately. If yours won't start you may have to loosen the distributor hold down and twist the distributor a little bit one way or the other before it starts. Once I got this set right at 0 degrees, I tightened the hold down and cleared the code and she runs perfectly again.

Look at this thread and do exactly what the guy "bronyaur" said.

https://www.gm-trucks.com/forums/topic/211999-misfire-issues-with-98-yukon

Thanks for this.

I have a Tech 2 that I’m using to monitor that PID. That’s where in getting the +30deg from.

Once the new bracket comes in that allows for adjustment of the distributor I will try twisting it, but I was under the impression that you twist if for final adjustment with the scanner... say a few degrees.

With me being a full 30deg off already, it sure seems like it’s a tooth off or more. But advancing or retarding the teeth by one has made it where it won’t run.

It is in fact running at the +30deg, but not very well.

Do you remember how much offset you were able to adjust for by twisting your distributor?

 

[geeeee89]

Thanks for this.

I have a Tech 2 that I’m using to monitor that PID. That’s where in getting the +30deg from.

Once the new bracket comes in that allows for adjustment of the distributor I will try twisting it, but I was under the impression that you twist if for final adjustment with the scanner... say a few degrees.

With me being a full 30deg off already, it sure seems like it’s a tooth off or more. But advancing or retarding the teeth by one has made it where it won’t run.

It is in fact running at the +30deg, but not very well.

Do you remember how much offset you were able to adjust for by twisting your distributor?

I added some stuff to the post after you quoted me by the way, just so you don't miss anything.

I still have the factory hold down bracket on mine, not sure about yours.

I stabbed my distributor using the alignment marks I made before I removed it, and when I put it back in, it wasn't exact, but at TDC on #1 the rotor was pointing "pretty much" at cylinder 1. I figured that was close enough and could adjust afterwards, which is what I did. So if yours is that close you'll be good but you may need to stab it again, I had to stick a screwdriver in the distributor hole and twist the oil pump to help line it up.

If you have it running already you should be able to twist it enough to get it at 0. Mine was a little over 18 degrees off and I had plenty of room to twist it to 0

 

[Fragment]

I added some stuff to the post after you quoted me by the way, just so you don't miss anything.

I still have the factory hold down bracket on mine, not sure about yours.

I stabbed my distributor using the alignment marks I made before I removed it, and when I put it back in, it wasn't exact, but at TDC on #1 the rotor was pointing "pretty much" at cylinder 1. I figured that was close enough and could adjust afterwards, which is what I did. So if yours is that close you'll be good but you may need to stab it again, I had to stick a screwdriver in the distributor hole and twist the oil pump to help line it up.

If you have it running already you should be able to twist it enough to get it at 0. Mine was a little over 18 degrees off and I had plenty of room to twist it to 0

Thanks

I kept the original bracket from the old engine... but have subsequently lost it. So I’m waiting for a new one to come in this week. The one that came with the Chinese distributor allows for no adjustment whatsoever. Id imagine it has to be stabbed correctly if it’s running and not stalling at idle. So hopefully it’s just a twist away.

 

[geeeee89]

Thanks

I kept the original bracket from the old engine... but have subsequently lost it. So I’m waiting for a new one to come in this week. The one that came with the Chinese distributor allows for no adjustment whatsoever. Id imagine it has to be stabbed correctly if it’s running and not stalling at idle. So hopefully it’s just a twist away.

You'll find it as soon as the new one comes in lol and I agree on it being stabbed correctly. Shouldn't take you more than 15 mins to get it dialed in

 

[Schurkey]

My 454 L29 showed 29 degrees offset when I bought the truck. I could turn the distributor to get to 1 degree.

That's probably all you need to do.

HOWEVER, I'd look at the gear and rotor on the distributor. The gear should have a "dot" or "dimple" drilled into it, that "dot" should align with the distributor rotor tip. If it doesn't, the gear is 1/2 a tooth misaligned.

 

[Suds]

The gear should have a "dot" or "dimple" drilled into it, that "dot" should align with the distributor rotor tip. If it doesn't, the gear is 1/2 a tooth misaligned.

Shocking to say the least that a BRAND NEW Delphi dizzy had the dimple on the gear and a permanent white mark on the shaft which was marked through with a black Sharpie and a new mark was made with their Sharpie to the right of it. I was like what??????? Lol

 

[Pinger]

I’ve stabbed the distributor in at least 20 times and have verified TDC and followed the instructions I’ve found on this forum as well as the service manual... but I consistently have about +30 CKP retard and consequently get the p01345 code and poor running.

!

A couple of questions.
As per the the link to GMTruck .com '' I haven't seen the code come on until its around +/-14.''
If the value is out (by more than that), it will throw the P 01345 code which will be readable on any diagnostic screen that can read 'P' fault codes - yes?

I still don't understand this. I was told that the dizzy being in the right place affected cross-firing within the cap, and misfire detection (attributing to relevant cylinder). I don't understand why the OP's engine is running poorly (as it isn't in the cross-firing within the cap scenario). Why so?

 

[Schurkey]

it will throw the P 01345 code which will be readable on any diagnostic screen that can read 'P' fault codes - yes?

Yes.

I was told that the dizzy being in the right place affected cross-firing within the cap, and misfire detection (attributing to relevant cylinder).

Yes.

I don't understand why the OP's engine is running poorly (as it isn't in the cross-firing within the cap scenario). Why so?

More than just the P01345 wrong?