I have a lmm with danville tuning which the big tune is 530 horse I just installed a air dog 150 and still every now and then the fuel filter life will drop to zero. Then it says change fuel filter but I don't get a low rail pressure code. Still has the stock fprv which I have a race plug coming. I don't have a rail pressure gauge to monitor just boost and egts. Could it be the stock relief valve letting pressure off?
Lmm fuel filter life drops to zero
- Thread starter lb7duramax1993
- Start date
Mine has done the same thing and I have a shimmed FPRV and I'm not running near as much fuel as you are. Possibly a fuel pressure regulator issue? Are your injector(s) failing and returning too much fuel?
Is your truck an 08 by chance? We have had two 08s in the shop doing the same thing. One deleted h&s tuned and the other bone stock. We didn't spend a whole lot of time on them but fuel supply vacuum and rail pressures were in spec. Couldn't really get anywhere with it.
No I haven't checked lift pump pressure yet I just put the air dog on two days ago and the trucks a 07.
Check the fuel line where it comes up over the valve cover on the drivers side they tend to kink.
Here is a little write I did that might help you with diagnosis.
http://atptrucks.com/blog/fuel-rail-pressure-is-low-now-what/
http://atptrucks.com/blog/fuel-rail-pressure-is-low-now-what/
Is the stock filter head still on it? If so do you happen to have a WIX plastic filter on it? Just helped somebody on Sunday with an 08 LMM with fuel filter life dropping to 0 on 700 miles or any time he got on it, and throwing the P0087 code. He had put 2 WIX filters on it, and they both did the same thing. Ended up being the WIX filter didn't have the tab in the center of it to depress the check ball and allow fuel to flow through easily. Put an AC DELCO filter on it and he was all good.