1x/4x Debacle With Holley EFI
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1x/4x Debacle With Holley EFI Long story short....
Engine is a 402 LS2 with a 24x reluctor and 1x cam sprocket. It has a Holley Dominator EFI with an LS2 harness in it. The harness has been modified to get 12v to both the crank and cam sensors, and the pins on the cam sensor plug have been switched so the harness supports the 1x sensor. The car is having cam sensor issues, runs like dick unless I run the car on the crank sensor only. Once I switch over to crank sensor the car smooths out.
I have been trying to track down a cover mounted 12v 1x sensor, and I'm not sure that I've found any reliable information on what sensor to use. At this point, it appears OE#12585545, which superseded OE#12568983, is the correct way to go. This sensor is found on the 05-06 GTO if I'm not mistaken. Is this correct?
Also, I've seen random posts where people are mentioning the 4x sensor will operate just fine on a 12v power source and on a 1x sprocket. Is there any truth to that? And if there is, and I use a 4x sensor, I would revert the pins back to the original LS2 pinout, correct?
Thanks.
Engine is a 402 LS2 with a 24x reluctor and 1x cam sprocket. It has a Holley Dominator EFI with an LS2 harness in it. The harness has been modified to get 12v to both the crank and cam sensors, and the pins on the cam sensor plug have been switched so the harness supports the 1x sensor. The car is having cam sensor issues, runs like dick unless I run the car on the crank sensor only. Once I switch over to crank sensor the car smooths out.
I have been trying to track down a cover mounted 12v 1x sensor, and I'm not sure that I've found any reliable information on what sensor to use. At this point, it appears OE#12585545, which superseded OE#12568983, is the correct way to go. This sensor is found on the 05-06 GTO if I'm not mistaken. Is this correct?
Also, I've seen random posts where people are mentioning the 4x sensor will operate just fine on a 12v power source and on a 1x sprocket. Is there any truth to that? And if there is, and I use a 4x sensor, I would revert the pins back to the original LS2 pinout, correct?
Thanks.
Just run it in batch fire with the crank only. I had issues with my car doing the same thing. Changed the cover, sensor, gear, cam and eventually the block and they all had issues. Put the same ecu and harness in my other car and it runs perfect with the cam sensor turned on. Only thing I came up with is the one car must have had some kind of RF that was messing with it.
Tim
Tim
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So I actually have a few more questions in this. I’ve looked through a datalog and it appears that thr cam return is a digital rising (4x) vs single pulse (1x). So I’m going to get a 1x off an 05-06 GTO.
Question though. Are all of the 1x sensors pinned out the same? Or are all of the front sensors pinned out the same?
When I get the front 1x sensor, should it be wired like the LS1 or LS2?
Question though. Are all of the 1x sensors pinned out the same? Or are all of the front sensors pinned out the same?
When I get the front 1x sensor, should it be wired like the LS1 or LS2?
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Ok. So a timing cover mounted 1x sensor is pinned the opposite of a rear mounted 1x sensor?
Also, the timing cover mounted sensor works fine on 12v I take it since the common solution is to swap wires and extend, not reduce it to 5v like the 4x sensor?
Also, the timing cover mounted sensor works fine on 12v I take it since the common solution is to swap wires and extend, not reduce it to 5v like the 4x sensor?
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Alright, I just want to make a finalized post here since all the information I had researched came from multiple sources and was constantly conflicting. The Holley Dominator in this car is now showing a solid cam and crank signal.
The engine is an LS2 block with LS3 heads, running a 24x reluctor wheel and a 1x cam gear. The car has an LS2 harness made by Holley, for the Holley dominator.
In reality, the only thing that was necessary was getting the cam and crank sensor switched over to a 12v power source. Despite it being a 1x sensor, since it was a front mount, no wiring modifications were necessary for the cam sensor past the 12v power source (this is where I found the most conflicting/confusing information). The sensor that works well as a 1x sensor is the PC620 cam sensor found on Summit Racing. Link here: https://www.summitracing.com/int/par...c620/overview/
The engine is an LS2 block with LS3 heads, running a 24x reluctor wheel and a 1x cam gear. The car has an LS2 harness made by Holley, for the Holley dominator.
In reality, the only thing that was necessary was getting the cam and crank sensor switched over to a 12v power source. Despite it being a 1x sensor, since it was a front mount, no wiring modifications were necessary for the cam sensor past the 12v power source (this is where I found the most conflicting/confusing information). The sensor that works well as a 1x sensor is the PC620 cam sensor found on Summit Racing. Link here: https://www.summitracing.com/int/par...c620/overview/
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From: Aurora CO
Alright, I just want to make a finalized post here since all the information I had researched came from multiple sources and was constantly conflicting. The Holley Dominator in this car is now showing a solid cam and crank signal.
The engine is an LS2 block with LS3 heads, running a 24x reluctor wheel and a 1x cam gear. The car has an LS2 harness made by Holley, for the Holley dominator.
In reality, the only thing that was necessary was getting the cam and crank sensor switched over to a 12v power source. Despite it being a 1x sensor, since it was a front mount, no wiring modifications were necessary for the cam sensor past the 12v power source (this is where I found the most conflicting/confusing information). The sensor that works well as a 1x sensor is the PC620 cam sensor found on Summit Racing. Link here: https://www.summitracing.com/int/par...c620/overview/
The engine is an LS2 block with LS3 heads, running a 24x reluctor wheel and a 1x cam gear. The car has an LS2 harness made by Holley, for the Holley dominator.
In reality, the only thing that was necessary was getting the cam and crank sensor switched over to a 12v power source. Despite it being a 1x sensor, since it was a front mount, no wiring modifications were necessary for the cam sensor past the 12v power source (this is where I found the most conflicting/confusing information). The sensor that works well as a 1x sensor is the PC620 cam sensor found on Summit Racing. Link here: https://www.summitracing.com/int/par...c620/overview/
Reviving this thread to hopefully get clarification.
So the sensor there on summit you listed was the fix?
Right now fighting an issue with my 6.0, it's a gen 4 but swapped reluctor wheels for the 24x and moved the cam sensor to the front using a delphi sensor. It's only firing 2 maybe 3 cylinders at the moment. The cam sensor I got is a 2005 GTO but it says 5v reference. I've read here though any sensor should work on 5v or 12v
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Reviving this thread to hopefully get clarification.
So the sensor there on summit you listed was the fix?
Right now fighting an issue with my 6.0, it's a gen 4 but swapped reluctor wheels for the 24x and moved the cam sensor to the front using a delphi sensor. It's only firing 2 maybe 3 cylinders at the moment. The cam sensor I got is a 2005 GTO but it says 5v reference. I've read here though any sensor should work on 5v or 12v
So the sensor there on summit you listed was the fix?
Right now fighting an issue with my 6.0, it's a gen 4 but swapped reluctor wheels for the 24x and moved the cam sensor to the front using a delphi sensor. It's only firing 2 maybe 3 cylinders at the moment. The cam sensor I got is a 2005 GTO but it says 5v reference. I've read here though any sensor should work on 5v or 12v