2006 LS2 cam position P0340

We put a 2006 LS2 with 45,000 miles on it in a 68 Caddy about 8 years ago. The guy we did it for just got it back finally from getting painted. When we tried to start it it didn't want to start. So we cleaned the fuel system put new injectors and plugs in it and it started so we could move it. So now I got the gages in it and we can see it has a engine code P0340 cam position circuit malfunction. And it starts hard every few times back firing thru the exhaust. we changed the cam sensor and the code has not gone away and either has the problem. we checked continuity of the wires back to the computer and they seemed fine. The wire harness is from Street and Performance who is no longer around to ask questions. Has any one else experienced similar problems and came up with a solution? Or what and how can I check this system. I am out of town for the week I can post tune files when I get back home.

Attachment 158678

Attachment 158677

So I'm back from vacation. I tried to read the computer for this LS2 and I get some errors. (this keeps getting better) I took some pictures of the errors but I can't seem to download them on to here. But it is a E40 ECM, GM Gen 4 V8/ 2006 Pontiac GTO 6.0 L
I get this error: Controller unlocker: x35 invalid key / controller unlocker: x36 exceed number of attempts
Does this mean the ECM is locked?
Can I unlock it with HPT?

If the computer is also from Street and Performance, it will most likely be locked.

I have a different computer on the way so we can start fresh.

Verify the cam is pinned properly as blindsquirrel stated. GTO vehicles were Australian based platforms and didn't use the CAM extension from GM. Position's A and C may need to be switched if it was wired for the wrong connector.
Is your wiring harness plugging directly into the cam or do you have the common GM cam extension that plugs into the cam and provides a more convenient plug in location to the oil pan? Do you have a photo of your cam connector?

Street and Performance used some guy named Tony to do their files and he always seemed to lock them for whatever reason.

The wire harness is plugged directly into the sensor there is no harness on the front of the engine like I have seen on other LS engines. I don't have a pic of the cam connector. We had a good relationship with Tony years ago but lost contact with him once Street and Performance closed down.

I've been saying I think it would be smart to try one of those jumper harnesses. It should have had one

If CMP 'A' goes to C2 44, and CMP 'B' goes to C2 15, and CMP 'C' to C2 26, it doesn't matter what position the wires are in when (or if) they pass through an inline jumper/connector.

We checked continuity of the wires from the sensor to the computer and they all checked ok. I will double check tonight that they are in the correct locations.

The wiring is a little confusing. The plug that goes into the sensor is labeled A - B - C (that plug is on my Street and Performance harness so that could be wrong) and in the schematics the plug is labeled A - C - B. My ground wire on my plug is in the middle of the plug. From the schematics it looks like it should be on the end of the plug in position B? Or am I looking at this wrong.

I believe I have this sorted - GTO has no extension/jumper, so the pinout shows the positions at the sensor. The others that have the extension/jumper, the pinout shows that connector between the main harness and the extension and the pinouts at the sensor itself are not described anywhere in the manuals.

Attachment 159012 Attachment 159013

Attachment 159014 Attachment 159015

If the pins are marked on the sensor itself, use those (match to the wiring diagram). Sometimes the labels are down inside the connector beside the pins.

Thanks blindsquirrel I appreciate all your help. I'll have to pull that sensor and see if I can see any letters on it. I don't remember seeing any but I'll have to look closer.

The sensor won't have letters but the CONNECTOR will. You may have to remove the white 3-way TPA lock. NChevelle71 when you see the schematic, it doesn't have the letters in "order" but that doesn't matter. A is A, B is B, and C is C regardless of what arrangement they show on a schematic. Post a picture of your CONNECTOR please. It's not uncommon for folks to FORCE or manipulate a connector that is A B C into a plug it's not supposed to be in by modifying the key-way. However, the goofballs at GM have A and C in different positions depending upon which CAM connector you have and it matters if you're plugging directly into the cam itself OR the OEM Jumper harness that you likely do NOT have since it's a GTO engine unless you were told by Street and Performance to do so to fit their harness.

Since you stated you're plugging directly into the CAM itself, which is normal for AUS based engines, I would like to see a picture and I can assist you on the pinout!

relicdew I have had the white lock off of the connector to see the A B C markings. I will take some pics tonight.

I checked the wires from the connector to the computer last night and
"A" red wire goes to 44
"B" black wire goes to 15
"C" brown wire goes to 26

I attached some pics (hopefully). On the inside of the sensor you can see "+" / "-" / "O" marked

Does "A" = "+", "B" = "-", "C" = "O"? (the markings should correspond to +ref, gnd ref, & output)

This may sound crazy, but has anybody looked through the little hole in the timing cover yet to see if it has the right cam sprocket on it?

Yes the "A" = + , "B" = - , "C" = O. I ran out of time last night so I didn't look into the hole. I did try to feel if the sprocket was loose but it seemed fine. The new computer should be here in the next few days so we can give that a try. Does anyone have some info of what I should do to the computer for a good start up tune? I know I need to turn the Vatts off but what else should be done to start? Thank you guys for all your input.

have you tried a new sensor? The china on that worries me.. lots of bad brand new parts lately.

And yes check the cam reluctor if you can. It should be a big half moon.. nothing else. This got our shop this week. ZL1 that caught on fire after customer installed his own brand new motor in his own garage. It was towed to us and we repaired the harness because they are impossible to find, won't start for us.. our first thought is our harness repair went wrong somewhere... But I know GEN 4's sometimes will not start with a bad cam signal. pulled the cam sensor out and saw the wrong reluctor wheel behind it.

I feel so lucking finding that.. that had the potential to waste a lot of shop time.

This is what you should have.. and what my ZL1 customer this week shouldn't have had. lol

Attachment 159078

Quote:

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Originally Posted by NChevelle71

The new computer should be here in the next few days so we can give that a try. Does anyone have some info of what I should do to the computer for a good start up tune?

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Don't pay to license it until you've gone through all the normal diagnostics with the old one still in the car. Chances of the old ECM being bad and causing this is about nil.

Pretty sure they have the harness pinned as if it was plugging into the jumper harness, and you need to swap A & C. I'd need to be able to see all of the pics/diagrams visible on the same page at the same time, having them in separate tabs isn't cutting it this morning. My head is doing that thing where it feels like there is a white-hot ice cube lodged between my brain and the inside of my skull.

That is a new sensor. I saw the China label last night and thought it was odd. The sensor was bought at a GM dealer and was in a GM bag. I'm not saying it couldn't be bad. Because it seems like lately lots of automotive parts are poorly made. I'll have to question the dealership I bought it from. I'll have to look thru the hole on Sat at the cam sprocket.

LOL. I get it blindsquirrel I felt the same way last night looking thru all the diagrams.

No, this is a migraine. I can usually keep the pictures up on my internal screen when switching from one to another but that system is offline right now.

OH sorry to hear that!

OK, I'm about to paste in a block of text. It is a properly formatted block of text. The forum is going to choke on it and display it wrong. Ready? Go!

2005 corvette - no extension
A OG 631 12vref 44 (12vref)
B PK/BK 632 loref 15 (loref)
C BN/WH 633 signal 26 (signal)

2005 GTO - no extension
A BN 633 signal 44 (12vref)
B RD/WH 632 loref 15 (loref)
C WH/BK 631 12vref 26 (signal)

2006 impala (LS4) - no extension
A OG 631 12vref 44 (12vref)
B PK/BK 632 loref 15 (loref)
C BN/WH 633 signal 26 (signal)

2006 trailblazer - WITH extension
A RD 631 12vref 44 (12vref)
B PK/BK 632 loref 15 (loref)
C BN/WH 633 signal 26 (signal)

2005 grand prix - no extension
A RD 631 12vref 44 (12vref)
B PK/BK 632 loref 15 (loref)
C BN/WH 633 signal 26 (signal)

2007 silverado (E38) - WITH extension
A BU 6259 5vref n/a (12vref)
B BN 6266 loref n/a (loref)
C BU/WH 6255 signal n/a (signal)

♫ one of these things is not like the others ♫

(nice job mangling a block of plain text, forum. well done.)

If you would like to see that in a readable form: Attachment 159082

Oh, and the migraines are a regular thing. If it was a one-off I'd swear I was dying, but this is just normal by now.

So I'm feeling kind of stupid at the moment. So looking at the 2005 GTO "A" goes to 44 / "B" goes to 15 / "C" goes to 26 (which I believe is how mine is wired).
But I see "A" is 633 and "C" is 631 (different from the others). Do the circuit #'s not matter?

The GTO pinout (or the labeling, whatever, I'm mad at the GTO section of the manual right now) is wrong. All the others use the exact same sensor, and all but the Silverado are E40.

This is one of those super easy to solve with an o-scope deals. It's 3 wires. You can almost just swap em around until it works.

Thank you blindsquirrel for all the info.

Just an update. I found a guy in my area willing to take a look at this issue for me. With all the tools he uses he was able to locate some wires that were in the wrong positions at the PCM.
Changed them around and no more codes or starting issues. Thank you for everyone's input on this issue.

Quote:

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Originally Posted by blindsquirrel

The GTO pinout (or the labeling, whatever, I'm mad at the GTO section of the manual right now) is wrong. All the others use the exact same sensor, and all but the Silverado are E40.

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The official GM service manuals for the GTOs are riddled with errors. Some are just entire wire harness labels being off by one wire all the way down, some are not properly translated to left hand drive, and some errors show options that were never available to the U.S. market. Pretty sure whoever translated Monaro to GTO had recently been kicked in the head by a kangaroo. And you may already know this, but the ergot derived migraine meds that seem difficult to get in the U.S. are extremely effective and fast acting.

I've tried some of the meds as of like 15 years ago, which was the triptans and the ergot based ones. They either did nothing at all or did nothing for the migraine but did have pretty miserable side effects (nausea, which I miraculously don't get with just the migraines). I haven't tried any of the new gepants, those are promising because they are OK for daily/preventative use unlike the others. Which is about the only way any meds would be able to help with this.

GTOs only have seven ignition coils, according to the pinouts.

Quote:

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Originally Posted by blindsquirrel

I've tried some of the meds as of like 15 years ago, which was the triptans and the ergot based ones. They either did nothing at all or did nothing for the migraine but did have pretty miserable side effects (nausea, which I miraculously don't get with just the migraines). I haven't tried any of the new gepants, those are promising because they are OK for daily/preventative use unlike the others. Which is about the only way any meds would be able to help with this.

GTOs only have seven ignition coils, according to the pinouts.

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Interesting. I guess everybody is different. I know 2 people who had great results with ergotamine and cafergot without negative side effects. Wait until you try to find the ambient air temp sensor or cell modem on a GTO, lol.