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Discussion Starter #1
I need to replace the CPS on Bank 2 of my V6 engine because I've got the P0346, P0300, P0306, P0305, and P0304 codes. I've looked all over the internet for a video or DIY guide on replacing it, but either there isn't one, or I haven't looked hard enough. I found a 4-minute YouTube video that shows a guy putting a new one on, but it wasn't very helpful in my opinion. So if anyone has one or at least some basic instructions, with or without pictures, I'd appreciate it, even though it's supposed to be an easy job.
 

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The CPS is on the back of the head directly behind the intake camshaft, it has one connector and is held by two bolts.
It is quite simple to replace, but I think you problem is more likely to be a timing issue.
It could be a broken CCT shoe. top or bottom. This is serious and if not fixed it could destroy the engine.
I suggest you check the valve timing.
 

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Discussion Starter #3
The CPS is on the back of the head directly behind the intake camshaft, it has one connector and is held by two bolts.
It is quite simple to replace, but I think you problem is more likely to be a timing issue.
It could be a broken CCT shoe. top or bottom. This is serious and if not fixed it could destroy the engine.
I suggest you check the valve timing.
I just had the timing belt, belt tensioners, cam chain tensioners, tensioner gaskets, cam seals, cam plugs, and half moon seals replaced. The car runs perfectly fine at idle in Park, Neutral, Drive, and under acceleration. It was a bit rough when I picked it up from my mechanic, but I think that was because the cams, seals, and tensioners were dry. But it's very steady at idle, it doesn't surge or shake. It used to have a code for over-advanced cam timing, but that was before I had all of this stuff replaced, and it's gone now. The CEL only flashes very intermittently, and even then the engine still feels very smooth.
 

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henrod, I suggest you talk to your mechanic. Highly unlikely that code would just pop up out of the blue after all that was changed out unless the timing was out. Could be only one tooth. The fact that it is coupled with misfires on one side only is more telling of a timing issue. IIRC, 4-5-6 is on the left side (driver side US)

The code doesn't always mean that the sensor is faulty. It just says it is receiving an implausible signal. One of the causes for that implausible signal is engine timing being out.
 

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I've got the P0346, P0300, P0306, P0305, and P0304 codes
I just had the timing belt, belt tensioners, cam chain tensioners, tensioner gaskets, cam seals, cam plugs, and half moon seals replaced. The car runs perfectly fine at idle in Park, Neutral, Drive, and under acceleration. It was a bit rough when I picked it up from my mechanic, but I think that was because the cams, seals, and tensioners were dry. But it's very steady at idle, it doesn't surge or shake. It used to have a code for over-advanced cam timing, but that was before I had all of this stuff replaced, and it's gone now. The CEL only flashes very intermittently, and even then the engine still feels very smooth.
Some of these things don't make sense.
You are having lots of misfires....and yet you say the engine is running smooth? how rough was it running before?
When I would get a random misfire on one cyl the engine would run rough...and you have half your engine misfiring...

all of that work was done and you are getting misfires along one bank, was the VC properly replaced and torqued? (and then left for a few hours and come back and then torqued again?)
 

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I just had the timing belt, belt tensioners, cam chain tensioners, tensioner gaskets, cam seals, cam plugs, and half moon seals replaced. The car runs perfectly fine at idle in Park, Neutral, Drive, and under acceleration. It was a bit rough when I picked it up from my mechanic, but I think that was because the cams, seals, and tensioners were dry. But it's very steady at idle, it doesn't surge or shake. It used to have a code for over-advanced cam timing, but that was before I had all of this stuff replaced, and it's gone now. The CEL only flashes very intermittently, and even then the engine still feels very smooth.
In that case I suggest you clear the codes and re-check.
If the codes come back it indicates a timing error, I would take it back to the mechanic to fix the timing.
 

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Discussion Starter #7
Some of these things don't make sense.
You are having lots of misfires....and yet you say the engine is running smooth? how rough was it running before?
When I would get a random misfire on one cyl the engine would run rough...and you have half your engine misfiring...

all of that work was done and you are getting misfires along one bank, was the VC properly replaced and torqued? (and then left for a few hours and come back and then torqued again?)
It's actually running better than it was before I had those items replaced. The mechanic told me that someone who owned the car before me tried to work on the chain tensioners himself, but he did a half-assed job, and that's why it had an over-advanced cam timing code on Bank 2. I just drove it earlier today to a friend's house about 10 miles away from where I live, and the CEL wouldn't stop flashing when I was traveling on a two-lane road, going 45-50 MPH, and the engine turning at 1800-2000 RPM, but again, it was very smooth, and it didn't surge or stumble. I checked the codes when I got there, and a P0456 was set, and a Check Gas Cap light came on while I was driving. I replaced the gas cap a few days ago, and a few days after that, I found a vacuum leak that 𝘸𝘢𝘴 causing it to run rough, but I reattached the hose, and that solved the problem. I haven't returned home yet, so I'll see what happens when I head for home, and I'll let you guys know. I haven't checked the valve cover (I think that's what you mean by VC), but I guess I will in a few days. I live in South Alabama, so a tropical storm is about to come through and it'll rain during this weekend and most of next week.
 

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War Eagle....... cam sensors rarely go bad, the chain count between sprockets IIRC is just a little different from bank to bank. The other thing is the new CCT installed, if the install tool is over compressed internal damage can occur to piston spring and plastic "stop pin" . First check integrity of electrical connections since everything was disconnected. This is my opinion......if I see only a "timing advanced" or only a "timing retarded" ,I lean towards bad count/installation if I see both I lean towards bad/damaged/worn CCT.
 

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It's actually running better than it was before I had those items replaced. The mechanic told me that someone who owned the car before me tried to work on the chain tensioners himself, but he did a half-assed job, and that's why it had an over-advanced cam timing code on Bank 2. I just drove it earlier today to a friend's house about 10 miles away from where I live, and the CEL wouldn't stop flashing when I was traveling on a two-lane road, going 45-50 MPH, and the engine turning at 1800-2000 RPM, but again, it was very smooth, and it didn't surge or stumble. I checked the codes when I got there, and a P0456 was set, and a Check Gas Cap light came on while I was driving. I replaced the gas cap a few days ago, and a few days after that, I found a vacuum leak that 𝘸𝘢𝘴 causing it to run rough, but I reattached the hose, and that solved the problem. I haven't returned home yet, so I'll see what happens when I head for home, and I'll let you guys know. I haven't checked the valve cover (I think that's what you mean by VC), but I guess I will in a few days. I live in South Alabama, so a tropical storm is about to come through and it'll rain during this weekend and most of next week.
I reset all of the codes before I drove back home, checked the codes when I got home, and I got P0346, P0300, P0306, P0305, and P0304. No emissions codes or gas cap lights though. The CEL flashed about 75-85% of the trip, only stopping for about 20-30 seconds before it started flashing again. Still ran perfectly smooth, no stumbling or surging. The CEL seems to only flash during deceleration, when I'm tipping-in to the throttle, and when it's at a steady engine speed while I'm driving. It doesn't flash at idle, nor does it flash when I'm taking off from a stop sign or traffic light.
 

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as a caveat to this...... at idle, I believe the CCTs are not doing anything proactive, I have disconnected my cam sensor while running and no errors as to timing occurred leading me to believe this.
 

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Discussion Starter #11
War Eagle....... cam sensors rarely go bad, the chain count between sprockets IIRC is just a little different from bank to bank. The other thing is the new CCT installed, if the install tool is over compressed internal damage can occur to piston spring and plastic "stop pin" . First check integrity of electrical connections since everything was disconnected. This is my opinion......if I see only a "timing advanced" or only a "timing retarded" ,I lean towards bad count/installation if I see both I lean towards bad/damaged/worn CCT.
I wonder if that explains the P0021 code that the car had before I had the tensioners replaced.
 

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You could flip flop bank 1 to bank 2 cam sensors and I doubt codes would flip flop. Your timing is off,either wrong count on chain/sprockets or sticky CCT.
 

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I will defer to my colleague Tomvw ,I believe he posted years ago an illustration of the differences of the chain/sprocket count/configurations between bank 1 and 2 on the V6.
 

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You could flip flop bank 1 to bank 2 cam sensors and I doubt codes would flip flop. Your timing is off,either wrong count on chain/sprockets or sticky CCT.
Well, I guess we'll have to find out. I bought a Bosch camshaft position sensor from Amazon for $55, but I forgot that I had a $65 gift card balance on my account, so at least I got a free Bosch CPS that's brand new. Stupid question, but when you disconnect the level sensor wire on the bottom of the coolant reservoir, will coolant spill out?
 

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So, I replaced the CPS on Bank 2. During the 2 hours of blood, sweat, and tears, I accidentally broke a vacuum line. After I put on a temporary line patch, I went on a 17 mile test drive, and the P0346 code didn't come back. I went to Autozone today to buy some vacuum hose to properly fix the vacuum line that I broke, and after that was fixed, I sprayed all of the vacuum lines behind the intake plenum with dish soap and water to see if I could find any other leaks. I took it on a 5 mile test drive, and all of the codes came back, including the P0346 code. 🤬 On the other hand, all of the codes were pending codes, and not active codes, so I don't know if I made any progress, or if my test drive wasn't long enough (probably the latter). I know that everybody on here says that the timing on that bank is off slightly, so is there anything else I can check before I call the mechanic up, give him hell, and then drive all the way to his shop?
 

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Well, you should have called him first before replacing anything. Now that you monkeyed around in there, they can blow you off using the excuse that you caused it.
 
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