Cam to crank sensor correlation fault

Is that -23 degrees the CMP Retard (Offset) value or the timing advance?


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It says

Ignition timing advance. #1 cylinder

And it’s on -23. Hooked the scanner up to my buddy’s obs same year and it reads 23. I couldn’t get mine to go to the positive.

It’s all in the terminology, if it says “advance” then it would not have the + sign since advance is before TDC and is negative by definition.

If it just said “timing” then it would include the negative sign to reflect advance/BTDC. Hope that made sense.

That yours says “advance” and has the negative number is kind of a double-negative and redundant.

The point being, the timing is controlled by the computer. The CMP offset, which is probably what is triggering your code, is set using a scanner that can read that value.

Was the distributor installed with it at TDC of compression stroke?


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Yes it was, one thing that has me really confused is that it runs better with it at -23 then it does at 0. It still run rough at -23 but it’s definitely better then at 0

Is the rotor aligned to the number 8 on the housing?






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This is the guide I used when I installed it. Once I set it in according to this guide it’s at -23. The only way I can get it to 0.0 is turning the distributor counter clock wise two teeth from where it’s suppose to be in this guide.

Hmm, the link didn’t show up...or did you mean the page I posted above?

As long as #1 was at TDC on compression stroke, the rotor should point to that number eight when fully seated.

https://www.diyforums.net/install-chevy-4.3l-5.7l-vortec-distributor-1065.html

Anyways, it’s not the ignition timing that you’re trying to get to read zero, it’s the CMP Retard that needs to be at zero degrees (plus or minus two) at around 1100-rpm. To get it to zero, loosen the hold down bolt and twist the distributor housing until the value is as close to zero as you can get. Tighten the bolt and it’s done. You won’t be physically pulling up the distributor, going to the next tooth and reseating it to get to the zero CMP Offset.

You’ve re-checked the wire routings? Try a Delco distributor cap if you get the CMP offset correct and still have the issue.




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east302 said:

Hmm, the link didn’t show up.

Anyways, as long as #1 was at TDC on compression stroke, the rotor should point to that number eight when fully seated.

https://www.diyforums.net/install-chevy-4.3l-5.7l-vortec-distributor-1065.html

Anyways, it’s not the ignition timing that you’re trying to get to read zero, it’s the CMP Retard that needs to be at zero degrees (plus or minus two) at around 1100-rpm. To get it to zero, loosen the hold down bolt and twist the distributor housing until the value is as close to zero as you can get. Tighten the bolt and it’s done. You won’t be physically pulling up the distributor, going to the next tooth and reseating it to get to the zero CMP Offset.

You’ve re-checked the wire routings? Try a Delco distributor cap if you get the CMP offset correct and still have the issue.




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The way your explaining it makes a little more sense to me now. I’ve got to get a scanner that’ll read the CMP not the ignition timing advance right?

This is the link to the guide I used.
http://www.gmtruckcentral.com/articles/distributor.html



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Yep, they’re two different numbers. I’d start with the CMP and get that set first.

When I did my lower gaskets and MPFI replacement, I ordered a $120 Palmer Performance OBD adapter that was supposed to work on an iPhone. Downloaded DashCommand, paid for the extended PIDs and it wouldn’t connect to the truck.

I dicked around with Palmer Performance for several days, they said it must be the adapter so I returned it for a refund.

I finally ended up getting the Android versions of it all and it worked fine. The cheapo android tablet, adapter and app were maybe $75 total.




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east302 said:

Yep, they’re two different numbers. I’d start with the CMP and get that set first.

When I did my lower gaskets and MPFI replacement, I ordered a $120 Palmer Performance OBD adapter that was supposed to work on an iPhone. Downloaded DashCommand, paid for the extended PIDs and it wouldn’t connect to the truck.

I dicked around with Palmer Performance for several days, they said it must be the adapter so I returned it for a refund.

I finally ended up getting the Android versions of it all and it worked fine. The cheapo android tablet, adapter and app were maybe $75 total.




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Alright east302 this is where I’m at now, I downloaded the DashCommand app and I’m using my OBD2 adapter. I’ve got the CMP to as close to 0 as I can. Now it’s showing misfires. I’m not sure in what order they appear in the DashCommand app, any idea ?


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