LLY no start after reluctor wheel repair

[mtl_dmax]

Ok folks I've got a bit of a stumper and I need the collective intellect to solve this one.

This is not my truck, I'm helping out a buddy on this. Anyway the truck came in on a flatbed to the dealer having died completely at a stoplight. The truck had a P0335 code, but the dealer ended up not being able to find the problem and the person was charged a huge number of diagnostic hours without fixing the issue. It was brought to another mechanic who worked on diesels (Ford guy) and he found the loose reluctor wheel and fixed it. After that he tried to start the truck as was unable to do so. I was told the truck sat almost a year and has had many people look at it (could have multiple issues), but no one has been able to figure out why it won't fire. Someone found out I worked on Duramax and I got the call to figure out the mystery.

Here's what I know:
1) Truck does make 4,000-7,000 psi fuel rail pressure (seems good IMHO)
2) Glow plug module, crank and cam sensors were all replaced (not sure it they were GM parts, possibly suspicious)
3) Engine will fire (one of the mechanics tried WD40 and it fired......yes, bad I know)
4) ECM is indicating "Injectors Disabled" for some reason (very suspicious)
5) CKP (crank) and CMP (cam) signals "passed" on the scanner (still suspect IMHO)


Any ideas are certainly welcome.

 

[rgullett83]

security light by chance? Any codes stored in the BCM?

 

[Bustedknuckles]

There's nothing wrong with running it on wd40 actually, starting fluid is a no-no though. The fact that it runs on alternate fuel tells me the engine and sensors are fine, and 7000 psi of rail tells me its capable of getting fuel. So either it cant burn the fuel (bad fuel) or its choosing not to. I suspect the latter since it says injectors disabled. I'm with rgullet, check for theft codes. You could try disconnecting the batteries and holding the leads together for a while to reset the ecm.

 

[mtl_dmax]

security light by chance? Any codes stored in the BCM?

I was told the security light would come on when the key is inserted and then go out, but I wasn't sure if it could still the the VATS preventing it from starting.

Wasn't sure if I should be trying something like this:
http://www.duramaxdiesels.com/forum/showthread.php?t=8662

Also do you need a Tech 2 to check the BCM codes or can it be done on other more capable scanners (Snap-on, etc)?

There are no current codes in the ECM except P0676 (ie #6 bad glow plug)

There's nothing wrong with running it on wd40 actually, starting fluid is a no-no though. The fact that it runs on alternate fuel tells me the engine and sensors are fine, and 7000 psi of rail tells me its capable of getting fuel. So either it cant burn the fuel (bad fuel) or its choosing not to. I suspect the latter since it says injectors disabled. I'm with rgullet, check for theft codes. You could try disconnecting the batteries and holding the leads together for a while to reset the ecm.

We tried just disconnecting the negative cables on both batteries without luck but didn't try holding the leads together.

 

[Bustedknuckles]

I was told the security light would come on when the key is inserted and then go out, but I wasn't sure if it could still the the VATS preventing it from starting.

Wasn't sure if I should be trying something like this:
http://www.duramaxdiesels.com/forum/showthread.php?t=8662

Also do you need a Tech 2 to check the BCM codes or can it be done on other more capable scanners (Snap-on, etc)?

There are no current codes in the ECM except P0676 (ie #6 bad glow plug)




We tried just disconnecting the negative cables on both batteries without luck but didn't try holding the leads together.

Snap on will check the codes but a tech 2 is ideal as it is factory. You need to hold the positive and negative together the reset the ECM.

 

[ku 808]

I had the same problem bought a not running truck well it came to be a broken cam found out when i did a compression test the owner was towing and it died dealer could not figuure it out so he sold it to me

 

[dmax711]

Are you sure cam and crank plugs are plugged into the rite sensor? They are the same plug and you can mess it up. Also if cam sensor and crank sensor got mixed up and they were installed in the wrong location it won't start. Just tossing out simple ideas for ya.

 

[mtl_dmax]

Snap on will check the codes but a tech 2 is ideal as it is factory. You need to hold the positive and negative together the reset the ECM.

I'm considering just loading EFI on this truck so I can disable VATS completely but will try the terminal trick for now.

I had the same problem bought a not running truck well it came to be a broken cam found out when i did a compression test the owner was towing and it died dealer could not figuure it out so he sold it to me

I'm thinking it's probably not that since this one clearly died because of the reluctor coming loose (low probability of both at the same time), but I will keep that in mind while looking though it.

Are you sure cam and crank plugs are plugged into the rite sensor? They are the same plug and you can mess it up. Also if cam sensor and crank sensor got mixed up and they were installed in the wrong location it won't start. Just tossing out simple ideas for ya.

No, I'm not sure they were correct, but the mechanic that installed them swore that they were installed in the correct locations and hooked up correctly (he made sure the parts person marked them acccordingly).

We do see both a cam and crank signal so that is why I suspected it was likely something else but will double check.

 

[ku 808]

well I did the same thing everything checked out it would fire and kind of start then die changed reluctor cam and crank sensor cp3 re did tuneing then I figured it out check compression if I only did that in the first place would have saved me a lot of time and $$

 

[mtl_dmax]

well I did the same thing everything checked out it would fire and kind of start then die changed reluctor cam and crank sensor cp3 re did tuneing then I figured it out check compression if I only did that in the first place would have saved me a lot of time and $$

Where did the cam snap?

Did you only get compression in a few cylinders?

 

[Auctioneerhere]

It would sure be helpful when a person gets a problem fixed if they would post the outcome.

 

[Burn Down]

It would sure be helpful when a person gets a problem fixed if they would post the outcome.

Yep, huge pet peeve of mine.

 

[mtl_dmax]

I ran out of time to work on it so the owner took it to the dealer and I have no idea what happened to the truck after that (ie was it fixed or traded).....sorry.