i've got a 08 lmm 3500. it has the tsperformance mp8, air raid cold air, magnaflow 5 to 6" exhaust, and the ppe race valve, oh and what it is worth 69000 on the clock. the problem i had before was getting a low fuel rail pressure sensor code. got that fixed (i thought with the race valve and changed the filter). well now i'm getting a p0401 code which is dealing with the egr. THIS ONLY HAPPENS WHILE TOWING. today while towing i got the low fuel rail pressure sensor code again (truck went into limp mode), also the egr code, and also service cluster read CLEAN EXHAUST FILTER NOW SEE OWNERS MANUAL. my question is what could be causing the low fuel rail pressure code. i'm not worrying about the dpf cause tuesday a delete pipe will go into place of the dpf and cat along with the hot race box from ppe so i can deleted the dpf and cat. the ts is coming off. again what could be the cause of the fuel rail pressure code? IT ONLY HAPPENS WHILE TOWING. does the dpf effect the fuel rail pressure sensor in any way? you can run the guts out of this truck while not towing and nothing will come up. it only happens while towing. today sucked when it went into limp mode on i75 downtown cincinnatti with around 10,000lbs of tool storage behind me. any help is gladly appreciated. thanks
!!!!!!!help!!!!!!!codes are back
- Thread starter scully
- Start date
You obviously are running a pretty big tune. you need a lift pump and you need to shim your Fuel Pressure Relief Valve.
The PPE should take care of the EGR codes.
Get rid of the TS and DPF
The PPE should take care of the EGR codes.
Get rid of the TS and DPF
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I've seen 3 LMMs recently have a MAP sensor go bad...Not sure if it's your problem, but just a thought...
Do you have a lift pump
You have never stated that you do. They do not come with lift pumps from factory, your CP3 sucks it all the way from the fuel tank.
You can do a bottle test to see if the race valve is leaking fuel past. Also dont get mad when the dealer voids your warranty if they see the race valve and the info in the ecm and tcm from the extra power from the TS box.