New to the site and have a big issue with a truck i just bought. Appreciate any help/advice i can get. 07.5 lmm 2500 with 80k on it. All stock, 2nd owner dealer serviced according to carfax. Ive had the truck for 7000 miles and it threw 4 codes. Egr valve sensor, turbo underboost, etc. Changed the egr valve (should of spent $ on efi live and delete but i didnt). Had 11 codes after that. Reset computer and was up to 15 codes. I brought the truck to the dealer at this point since i work 70+hrs a week and dont really have spare time. They resolved the codes, threw a new ecu in and some glow plugs. All codes gone until the last mile of the test drve. Truck went back into limp mode. Now its back to turbo underboost, sensor position not learned. Fix as im told, vain in turbo is bad and needs a new turbo. $4000, trans has to come out. My question is, can this happen at 80k miles? And would i be better off upgrading the turbo, egr,dpf delete, efi live for more or less same $? Any suggestions are much appreciated.
lmm turbo issue
- Thread starter cwoz10
- Start date
Just replace the vain solenoid And sensor and go drive the piss out of it with a trailer behind you to blow the built up carbon out of the turbo. If you know someone with EFI live you can get them to Logg your truck to see what is wrong with the turbo, it is either the sensor isn't seeing the vains move or the solenoid isn't moving them. These trucks will build up carbon if not driven like they were designed for...
And the trans most definitely does not need to come out for a turbo swap. My guy does them for 400 bucks thru the wheel well...
Also, you cat could be clogged up, it's rare but I've seen it.
And the trans most definitely does not need to come out for a turbo swap. My guy does them for 400 bucks thru the wheel well...
Also, you cat could be clogged up, it's rare but I've seen it.
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Seems lmm's are more touchy with turbo codes than other models. It really should be logged with a tech II or efi live to determine what the vane position is. The turbo could be taken off and cleaned or pull the sensor out of it, clean it and then just run the ever living piss out of it. I mean rail the shit out of it. If it was mine I would delete it. Also turbo removal takes a couple hours with basic hand tools. No trans removal needed.
Anyone who can remove a LMM turbo in a couple hours, I will take them all my work. The coolant crossover and egr cooler is much larger, it is no where near the same as a LLY or LBZ, they suck...
Its definitely an all day job for R&R but pulling the tranny is unnecessary for sure.
Mechanic said he can manually move the sensor and it reads so the sensor is not bad. He said the vein in the turbo isint telling the sensor to move if that makes sense. Getting the truck back tomorrow and ill update with exact code it has. Sensor position not learned is what he told me on the phone.