P0045 when cold?

[Boost]

Why would an LLY throw a P0045 every time it's really cold? (Around 40 degrees here)
It's "TURBOCHARGER BOOST CONTROL SOLENOID CIRCUIT". I would like to figure out exactly why this truck sets that code every time it's much colder than average. Anything to do with the tune, or is there possibly a GM update that makes it less sensitive? Or could it be a mechanical problem? Thanks!

[Boost]

I found this thread so far:

http://www.duramaxdiesels.com/forum/showthread.php?t=6999

Interestingly, the truck I am working with has also had trouble with going into limp mode and de-fueling. Although it is une thata stock turbo mild tune LLY and only sets the P0045 when the weather is much colder than usual. And it has not had any driveability issues lately.

This is the that's in it currently:

[Boost]

Anyone have any info on this possible GM Technical Service Bulletin?

#05-06-04-040 SMU - Revised DTC P0045 - (Jun 7, 2005)

[joecar]

This is what I pulled up, see attached.

http://forum.efilive.com/si/images/gmLogoFlat.gif

[Boost]

Thank you Joe!!

[killerbee]

without looking into this, my guess would be oil flow. Too cold to flow. IIRC, the vanes are actuated by oil. A thinner synthetic is what I would try.

[Boost]

Thanks! And what if the tune with the altered turbo operation makes it more sensitive for this code to set?? Oil still affect / improve the issue, or do I need to modify the settings as suggested in the thread I found?

[Boost]

still battling this issue, still clueless. What I've found is that on cold mornings when the truck is allowed to warm up, it doesn't set the code, but when you jump into the throttle on a very cold morning before full warm-up it sets the 45. It seems tune related. Could the emissions be affected and thus the reason for the out of range? I would really like to know what this monitor looks for and why it freaks on cold start boost. Turning off the MIL without fully understanding the issue seems a bit unprofessional. What about the 4.9 to 5.1 V?? I feel like a dummy on this one. Thanks! Runs great otherwise

[dmaxhumvee]

Might try your block heater if you have one installed? I'm in Oklahoma, it doesn’t get too cold here but the block heater helps. Another thing, upon converting my Humvee with a Duramax, many engines I ran across that had EGR, many of the turbo inlets I inspected were gummed up. The sludge reminded me of tar. It could be that the PCM is commanding vane articulation, they don’t move, the sensor witnesses this and the PCM throws the code?
Sounds to me that the vanes are not moving either due to low oil psi or they are seized up? I’d start by checking your intake tube and turbo inlet for ERG sludge build up. Last resort I’d check the oil return tube that connects to the bottom of the turbo and block for any oil coking as a result of the temperatures from the turbo exhaust inlet (Tube runs right between them).

[Boost]

Thanks for that advice, sounds logical. It hasn't popped up since the "extreme cold" (45-50 here) :)

[killerbee]

Thick oil. Are you using 15W-40?

Turns into a brick, just thinking that the vanes can't actuate w/o oil pressure at the actuator, IIRC. Wish this could be tested.

[dansdieselp]

I'm having the same issue with the LLY trucks here as well. Only happens when the elevated idle kicks in. Never used to do this last winter on any of the trucks. Makes me wonder if there may be a scripting error or bug in the software since we've had several updates since last winter.