24x CMP Vortec Question
24x CMP Vortec Question Running a vortec dizzy for cam position signal, and it is throwing a CMP code. I want to verify my wiring before running some tests on the sensor and then calling EFIconnection to ask for a potential warranty replacement.
Starting with how the regular LT1 24x cam sensor should be wired.
Red (A) Ignition Hot 12v source - Red 39
Pink (B) Ground source - Blue 61
Brown (C) Signal - Blue 73
Assuming they are right, I then took them and feed the Vortec harness as follows
Blue 73 -> Brown/White (B)
Blue 61 -> Pink/White (A)
Red 39 -> Red (C)
How bad did I mess that up?
Starting with how the regular LT1 24x cam sensor should be wired.
Red (A) Ignition Hot 12v source - Red 39
Pink (B) Ground source - Blue 61
Brown (C) Signal - Blue 73
Assuming they are right, I then took them and feed the Vortec harness as follows
Blue 73 -> Brown/White (B)
Blue 61 -> Pink/White (A)
Red 39 -> Red (C)
How bad did I mess that up?
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You have it wired correctly:
To determine if the sensor is working, monitor the two cam sensor PIDs through your scan tool:
Let us know if they are incrementing - one after the other.
Might also be a good idea to check there are no breaks in the wire harness from the CMP sensor to the PCM.
- A: PNK/BLK - Low Reference
- B: BRN/WHT - Signal
- C: RED - 12V Reference
To determine if the sensor is working, monitor the two cam sensor PIDs through your scan tool:
- CMP Low to High
- CMP High to Low
Let us know if they are incrementing - one after the other.
Might also be a good idea to check there are no breaks in the wire harness from the CMP sensor to the PCM.
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So, the PIDs look to be working, the numbers follow each other as far as HPtuners showed.
That is with a new cam sensor in there, so, looks like the dizzy was installed out of sync?
Is there anything that can be done to minimize the amount the PCM relies on the CMP signal?
That is with a new cam sensor in there, so, looks like the dizzy was installed out of sync?
Is there anything that can be done to minimize the amount the PCM relies on the CMP signal?
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Is there anything that can be done to minimize the amount the PCM relies on the CMP signal?
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Verdad Gallardo That only applies to starts though correct?
Being as the engine needs to come out to reset the CMP position, I will hope the tuner can get it running well and live with rough starts till I either drop the motor or just buy the regular LT1 cam sensor from you.
Being as the engine needs to come out to reset the CMP position, I will hope the tuner can get it running well and live with rough starts till I either drop the motor or just buy the regular LT1 cam sensor from you.
I would think that you can drop the k-member a few inches to facilitate the re-timing of the dizzy. THe hardest part is making sure you can see the mark on the dizzy body and then making sure where the rotor would line up with it at #1 TDC. Speaking from experience with the vortec dizzy, even if you're a tooth off it causes the vehicle to run like junk. I can only imagine that it would do the same and cause nothing but issues with the 24x. It's probably more worth taking the time to do it right then risk screwing up everything because the sensor is off and causing the PCM to try and do things it shouldn't. That's just me though.
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Speaking from experience with the vortec dizzy, even if you're a tooth off it causes the vehicle to run like junk. I can only imagine that it would do the same and cause nothing but issues with the 24x.
I understand completely now, my headaches came more from the cap and rotor being off than the cam sensor being out if whack. I thought it was the other way around since rotating the whole distributor body did absolutely nothing to help the way that truck ran. Makes sense now.
