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Those codes are kind of opposite each other so it's weird it's throwing both, circuit low and circuit high. Those codes are directly from the PCM thinking there is a problem with the cam position sensor/circuit, it's NOT a class 2 communication issue as it has nothing to do with it. The cluster is not the issue either. The tach signal comes from the PCM along with the other data over the class 2 databus and everything else is working just fine, and if there was a class 2 databus issue it still wouldn't throw those cam sensor codes.
Just to confirm, you didn't convert this to a front cam gear/sensor cover setup did you? It's still just using the OEM position cam sensor in the rear top of the block correct?
Fuel gauge randomly dropping to empty indicates the PCM thinks something is wrong with the sender, that's default behavior when it throws a fuel tank level sender code. Lots of C5/C6 corvettes have this problem with their age now.
The cam sensor is still in the factory location, in the back, up top behind the intake.
I'm not sure what else to try.
This all happened right after I installed the blower cam.
Just an update:
yesterday I removed the intake to recheck the cam sensor wire and the grounds on the back of the heads. Everything checked out perfect. The ground wires looked perfect. I scuffed the back side of the head down a little to make sure the surface was clean.
I ohm tested the cam sensor wires from the plug back to the PCM connector. All showed .000 ohms.
The red voltage wire showed 11 volts with the key on, engine off.
Today I swapped in a different gauge cluster. NO CHANGE.
Next step is to try another PCM.
Not sure what else to try at this point.
A buddy gave me oem cam sensor to try.
It's been a LONG time since I worked on an original LS1 but looking at your pictures of the cam gear you posted at the beginning, the cam gear looks "different" than I remember. What is that black ring on the back side of the gear? What cam gear is that?
Also you said your buddy gave you an OEM cam sensor, what sensor is in it right now? Is it just the original OEM sensor?
I guess at this point it's worth trying a new PCM loaded with your current tune to see if that fixes it, but I've never seen a failure like this before and I've seen a LOT of these things over the last 20+ years. I would still lean towards something mechanical that has to do with the cam swap since that's when the issue started.
It's been a LONG time since I worked on an original LS1 but looking at your pictures of the cam gear you posted at the beginning, the cam gear looks "different" than I remember. What is that black ring on the back side of the gear? What cam gear is that?
Also you said your buddy gave you an OEM cam sensor, what sensor is in it right now? Is it just the original OEM sensor?
I thought the same thing when I saw the cam sprocket. It looked different. After some research I found the receipt from the guy that I bought the engine from. This is a Cloyes 9 keyway adjustable cam/crank sprocket. That other thing your asking, I believe is a is a thrust washer? Or thrust bearing.
When I installed the cam, I planned on just lining the dots up. Did it before in the past never had a problem.
Well with the oil pump still on, that made it extremely hard to see the dot on the crank sprocket. However after getting my face inches from the sprocket, I believe I found it and got it lined up. That top picture you can see the dot from the cam sprocket and directly below it the dot or the "O" on the crank sprocket. I assumed this is Dot to Dot. Look at the Cloyes instruction sheet I attached and zoom in. You can see what I'm talking about.
Like I said, I bought this engine already built and If the shop that built it used a different keyway when putting the crank sprocket on, me lining the dots straight up could be screwjng things up.
Also you said your buddy gave you an OEM cam sensor, what sensor is in it right now? Is it just the original OEM sensor?
The cam sensor that is in the car currently is a new "Genuine GM" cam sensor that I got off of ebay.
This was the 1st thing I did when I started experiencing this tach issue.
I told my buddy about that ebay sensor I bought and he questioned how legit it was and he gave me a used, factory GM Ls1 cam sensor to try. Haven't tried it yet.
I thought the same thing when I saw the cam sprocket. It looked different. After some research I found the receipt from the guy that I bought the engine from. This is a Cloyes 9 keyway adjustable cam/crank sprocket. That other thing your asking, I believe is a is a thrust washer? Or thrust bearing.
When I installed the cam, I planned on just lining the dots up. Did it before in the past never had a problem.
Well with the oil pump still on, that made it extremely hard to see the dot on the crank sprocket. However after getting my face inches from the sprocket, I believe I found it and got it lined up. That top picture you can see the dot from the cam sprocket and directly below it the dot or the "O" on the crank sprocket. I assumed this is Dot to Dot. Look at the Cloyes instruction sheet I attached and zoom in. You can see what I'm talking about.
Like I said, I bought this engine already built and If the shop that built it used a different keyway when putting the crank sprocket on, me lining the dots straight up could be screwjng things up.
Well I've only ever seen one thing consistently **** up and that's aftermarket cam/crank gear sets. Personally I would be putting stock ones on it because I would bet money that the cam is offset forward a bit, just enough that the cam sensor isn't picking up on the rear reluctor like it should.
Okay, we might be on to something. I spoke to the technical assistants guys at Cloyes. Heres what I found out. Going by the looks of it in this picture and assuming that I had the 'O" in the 12 O'clock position, the machine shop used the 2A keyway slot, meaning I SHOULD HAVE used the 2A tooth for it to be installed "straight up"....however, I did not. I'm off 2 teeth. Email below from Cloyes.
Put a stock cam/crank set on it and I bet it will be just fine, adjustable **** is just going to **** **** up and 99% of the time completely unnecessary. That being said I've also seen people be off a tooth and it not throw cam position sensor codes like this, but with the stock gear set. It has to be related to the adjustable set itself and how it's spaced, etc.
Put a stock cam/crank set on it and I bet it will be just fine, adjustable **** is just going to **** **** up and 99% of the time completely unnecessary. That being said I've also seen people be off a tooth and it not throw cam position sensor codes like this, but with the stock gear set. It has to be related to the adjustable set itself and how it's spaced, etc.
Okay, I will look into installing a stock OEM style timing set. I did find this on Corvetteforum. Mine is off 2 teeth by the looks of it.
So I did confirm that the cam sprocket is off 2 teeth from the crank. I put a bore scope in the #1 spark plug hole just to see how far off from TDC I was. Here is the video of that. Hopefully have this back together in the next few days.
The start of the video is where I had it "dot to dot"
The end of the video is where the tooth labeled 2A is at TDC and this is where it needs to be since the machine shop used the 2A keyway slot when setting the crank sprocket.
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