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I own a 1996 Chevy Tahoe. It is a 5.7L Vortec with 4 door.

The engine is knocking and pinging and the power is sluggish after there were some servicing done and I can see that the CMP/CKP correlation is off in the scanner. Before I take the truck to the service to have it fixed, I would like to make sure about some things.

The servicing done was basically replacing the valve lifters. This procedure means the whole engine is disassembled and assembled again. I realized the distributor cap is not aligned correctly, thus there is some offset in CMP sensor readings.

Questions:

  1. Camshaft position sensor (this is the CMP/CKP correlation) gives -11 degrees at 1000 RPM. It should be 0 degrees, right?
  2. "Ignition timing advance" value though, is something around -26 degrees (could be +26 degrees as well, not 100% sure). What's the ideal value for this?
  3. Are these values related? I know #1 is fixed with distributor rotation but I don't know how #2 is fixed, or even if there is something to fix.

I own a 1996 Chevy Tahoe. It is a 5.7L Vortec with 4 door.

The engine is knocking and pinging and the power is sluggish after there were some servicing done and I can see that the CMP/CKP correlation is off in the scanner. Before I take the truck to the service to have it fixed, I would like to make sure about some things.

Questions:

  1. Camshaft position sensor (this is the CMP/CKP correlation) gives -11 degrees at 1000 RPM. It should be 0 degrees, right?
  2. "Ignition timing advance" value though, is something around -26 degrees (could be +26 degrees as well, not 100% sure). What's the ideal value for this?
  3. Are these values related? I know #1 is fixed with distributor rotation but I don't know how #2 is fixed, or even if there is something to fix.

I own a 1996 Chevy Tahoe. It is a 5.7L Vortec with 4 door.

The engine is knocking and pinging and the power is sluggish after there were some servicing done and I can see that the CMP/CKP correlation is off in the scanner. Before I take the truck to the service to have it fixed, I would like to make sure about some things.

The servicing done was basically replacing the valve lifters. This procedure means the whole engine is disassembled and assembled again. I realized the distributor cap is not aligned correctly, thus there is some offset in CMP sensor readings.

Questions:

  1. Camshaft position sensor (this is the CMP/CKP correlation) gives -11 degrees at 1000 RPM. It should be 0 degrees, right?
  2. "Ignition timing advance" value though, is something around -26 degrees (could be +26 degrees as well, not 100% sure). What's the ideal value for this?
  3. Are these values related? I know #1 is fixed with distributor rotation but I don't know how #2 is fixed, or even if there is something to fix.
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CMP/CKP correlation vs Ignition timing Vortec 5.7L

I own a 1996 Chevy Tahoe. It is a 5.7L Vortec with 4 door.

The engine is knocking and pinging and the power is sluggish after there were some servicing done and I can see that the CMP/CKP correlation is off in the scanner. Before I take the truck to the service to have it fixed, I would like to make sure about some things.

Questions:

  1. Camshaft position sensor (this is the CMP/CKP correlation) gives -11 degrees at 1000 RPM. It should be 0 degrees, right?
  2. "Ignition timing advance" value though, is something around -26 degrees (could be +26 degrees as well, not 100% sure). What's the ideal value for this?
  3. Are these values related? I know #1 is fixed with distributor rotation but I don't know how #2 is fixed, or even if there is something to fix.