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lb7diesel
January 28th, 2008, 04:02 AM
I put a very mild tow tune in a friends LMM. He was coming back from a rodeo pulling a 30' goosneck full of horses when the " Clean exhaust filter" light came on. He continued to drive it home when the 'Engine reduced power" flashed and the truck would only run 30mph. He had to drive another 50miles to get home. I loaded the stock file back in, and cannot get the truck to regen, or even not throw the reduced power code. It goes right into limp mode when started. What can i do to get this to regen? I was thinking of raising the DPF Pressures? This sucks..

camcojb
January 28th, 2008, 04:14 AM
It should clear the limp mode when you reflash the stock tune, but the "clean exhaust filter" message will remain. Head out to the freeway or somewhere you can maintain 40 mph or better for 15-20 minutes. It should start regen at that point, but you won't know as the message will remain until it completes the regen. Then it goes off and all is well.

Jody

lb7diesel
January 28th, 2008, 06:22 AM
It won't clear the Limp..I've reflashed stock several times. As soon as you start the truck within a minute it will say engine power reduced. Not sure what to do besides have him take it to the dealer.

camcojb
January 28th, 2008, 08:08 AM
It won't clear the Limp..I've reflashed stock several times. As soon as you start the truck within a minute it will say engine power reduced. Not sure what to do besides have him take it to the dealer.


I've had it go to limp, but not that fast. Fortunately on mine I can hit a 40+ mph road less than 30 seconds from my driveway, so it has always regenned.

He'll likely have to go to the dealer and do a forced regen in his case if you can't get up to speed before it goes reduced power.

Jody

lb7diesel
January 28th, 2008, 10:21 AM
That's what i'm thinking also..I'll have to break the bad news to him..

cook
January 28th, 2008, 04:28 PM
hi , i was under the assumpition that efi was capable to command regeneration of the dpf ?

camcojb
January 28th, 2008, 04:30 PM
hi , i was under the assumpition that efi was capable to command regeneration of the dpf ?

not yet.

Jody

cook
January 29th, 2008, 01:33 AM
how about using the scan tool and clearing the dtc ,maybe a couple of times, it has worked for me. LOREN

lb7diesel
January 29th, 2008, 04:59 AM
how about using the scan tool and clearing the dtc ,maybe a couple of times, it has worked for me. LOREN


5 Times with ST. + the 3 times i loaded the stock file back in, I believe it clears all dtc's after flashing.:nixweiss: No lucky..

Until we can command regen, It's not a good idea to add any fuel when stock dpf is activated..I believe once it get so clogged the DPF pressure sensors instantly send it into limp..And you can't regen in limp mode...So off to the dealer it goes.

cook
January 29th, 2008, 08:13 AM
hi ,if you know someone with a bully dog powerpup downloader for the lmm it has a command regeneration option Loren

mrrattle
February 5th, 2008, 02:44 PM
try pulling both pressure sensors out of the exhaust, just let em hang there in the breeze, now go for a drive and see if you can get a regen out of it.

this is the pressure sensors tubes, not the temperature sensors. sensors are wires, pressure tubes are stainless pipes.


if the soot mass in the dpf goes past about 48 grams the computer freaks out so to speak and wont regen, i have seen as high as 97 grams soot mass.

the more soot mass in the dpf the longer you have to drive.

the dpf costs about 2200 bucks to replace and is covered under warranty. so you could just take back to dealer and complain really loud, let em know what a piece of crap the epa forced down your throught. then ask em why the light duty truck does not have a regen switch like the medium duty.

lb7diesel
February 6th, 2008, 01:35 AM
try pulling both pressure sensors out of the exhaust, just let em hang there in the breeze, now go for a drive and see if you can get a regen out of it.

this is the pressure sensors tubes, not the temperature sensors. sensors are wires, pressure tubes are stainless pipes.


if the soot mass in the dpf goes past about 48 grams the computer freaks out so to speak and wont regen, i have seen as high as 97 grams soot mass.

the more soot mass in the dpf the longer you have to drive.

the dpf costs about 2200 bucks to replace and is covered under warranty. so you could just take back to dealer and complain really loud, let em know what a piece of crap the epa forced down your throught. then ask em why the light duty truck does not have a regen switch like the medium duty.


I'll do that next time if it happens. He took it to the dealer and said they were replacing the dpf due to a problem they've been having with them. It was completely clogged as they put it. The filter is on back order if that tells you anything..

Any ideas when efi will have a new release so we can command a regen?