I purchased a 2008 with 56 k. The dealer changed the oil and fuel filter. I put a programmer on it, (power pup) and it started sending " change fuel filter" at extreme setting. I then installed a shim kit . I started getting the message at all settings. The truck has about 1000 miles since they put the filter on. I got 1 code today stating low fuel rail pressure. So, today I put on a new fuel filter. I un installed the program and I still get the message with it stock. Any help ? I also made sure the valve didn't get damaged .
replace fuel filter msg
- Thread starter 1ceman
- Start date
The firt issue before shim kit, you were prolly seeing low rail pressure. In the LMMs (not sure about the rest) we'll tell you to change the fuel filter when you start dropping rail pressure.
The second issue, after you installed the shim, is that its prolly not tight enough, and fuel is going around it (you made it worse by installing the shim and not getting it tight enough). check you WOT rail pressure, or do a bottle test. I bet the fuel is going around the FPRV.
Tighten up the FPRV and it should go away. You may still get low pressure codes or filter message on the hot setting when the FPRV is fixed, but thats going to be due to not enough fuel (lift pump time).
The second issue, after you installed the shim, is that its prolly not tight enough, and fuel is going around it (you made it worse by installing the shim and not getting it tight enough). check you WOT rail pressure, or do a bottle test. I bet the fuel is going around the FPRV.
Tighten up the FPRV and it should go away. You may still get low pressure codes or filter message on the hot setting when the FPRV is fixed, but thats going to be due to not enough fuel (lift pump time).
mine did that .. anytime you loose pressure and/or get leak back its normally filter isnt tight or O ring or rings has air leak i leaned this the hard way .. puter thinks filter isnt tight ? good luck thats my 2 cents..
I agree with Mike, 100%. For some reason people think shimming the rail will make the truck hold better rail pressure, but that only works if the rail is popping open. I have never personally seen an LBZ or LMM that has blown open a FPRV, and even though I have asked several times, I have yet to see anyone post a log showing it either. Not saying it can't or hasn't, but it is nowhere near as common as it is on an LLY. Put a lift pump on it, and/or get rid of the Bully Dog if you don't want the code to come back anymore.
Ok, I appreciate it guys.
Mike, what do you mean that the shim isnt tight enough? The FPRV that God himself tightened?
I did tighten it as much as possible. I was getting afraid to damage anything if I tightened it more. Or are you talking about the amount of shims? I ended up using all 3 which put the thickness around .80 mm. Or do you think there is an o-ring not seated properly like on the fuel filter itself ? Meanwhile Im searching the site on how to do bottle test. (Found it.. Ill try it tomorrow)
Josh, I decided after reading many posts on many msg boards, to go ahead and shim it since I do eventually want to build up the HP. Not to mention it is a cheap upgrade. If the valve isnt popping open, then your saying there has to be some kind of leak possibly with an o-ring? Other than the fuel filter o-rings, purge nut on top, where else is there a possibility of leakage? I dont show any signs of fuel on the outside of it.
I forgot to mention earlier that when the low fuel msg comes on , the truck starts to fall on its face. Like lack of fuel (Obvious)
As far as the messages, I dont mind as long as its not damaging the truck due to a simple fix. I understand the increased stress from racing. I drag raced gas for years. Im trying to get enough to have a daily driver that has "NO" problem taking out most of the Dodges running around here. The only reason I have the power pup, is that I had it on a Ford 6.0 Van I used to own. Once this problem is resolved, I figured on replacing the lift pump.
I have a 30 day warranty from the used dealership, and Im wondering if its worth taking out the shims, programmer and let them try to resolve it before the time is up? Just in-case there is a faulty pump, etc.
(Thanks for bearing with me guys. I moved over from a 6.0 Power Joke) Im learning as much as I can on these Duramax's.
Mike, what do you mean that the shim isnt tight enough? The FPRV that God himself tightened?
I did tighten it as much as possible. I was getting afraid to damage anything if I tightened it more. Or are you talking about the amount of shims? I ended up using all 3 which put the thickness around .80 mm. Or do you think there is an o-ring not seated properly like on the fuel filter itself ? Meanwhile Im searching the site on how to do bottle test. (Found it.. Ill try it tomorrow)Josh, I decided after reading many posts on many msg boards, to go ahead and shim it since I do eventually want to build up the HP. Not to mention it is a cheap upgrade. If the valve isnt popping open, then your saying there has to be some kind of leak possibly with an o-ring? Other than the fuel filter o-rings, purge nut on top, where else is there a possibility of leakage? I dont show any signs of fuel on the outside of it.
I forgot to mention earlier that when the low fuel msg comes on , the truck starts to fall on its face. Like lack of fuel (Obvious
)As far as the messages, I dont mind as long as its not damaging the truck due to a simple fix. I understand the increased stress from racing. I drag raced gas for years. Im trying to get enough to have a daily driver that has "NO" problem taking out most of the Dodges running around here. The only reason I have the power pup, is that I had it on a Ford 6.0 Van I used to own. Once this problem is resolved, I figured on replacing the lift pump.
I have a 30 day warranty from the used dealership, and Im wondering if its worth taking out the shims, programmer and let them try to resolve it before the time is up? Just in-case there is a faulty pump, etc.
(Thanks for bearing with me guys. I moved over from a 6.0 Power Joke) Im learning as much as I can on these Duramax's.
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Your truck was having problems before because of the amount of fuel the Bully Dog was commanding on the Extreme setting, not because of anything to do with the FPRV. It seems to me when you shimmed the FPRV you created a problem since it was only doing it on the Extreme setting before and now it does it even on the stock setting. Do a bottle test, and I you see some fuel in it.
Like Josh said, now that you shimmed it, you have more problems. The shim is fine, but its the re-install that is the issue. You can remember how tight it was to remove, now go back and tighten that tight lol.
Just about the time you feel like it is so tight and you are going to break something, tighten it a little more lol..
If you want search for "bottle test" and do that, I am willing to bet as of right now at WOT you will see fuel....Which means the fuel is getting around the FPRV that you just shimmed.
Just about the time you feel like it is so tight and you are going to break something, tighten it a little more lol..
If you want search for "bottle test" and do that, I am willing to bet as of right now at WOT you will see fuel....Which means the fuel is getting around the FPRV that you just shimmed.
Ok, I was able to get the FRPV to move the slightest. I thought I was going to rip off the rail from the motor. It did seem to fix the message from coming up on stock setting, tow, and Performance. On Performance, it does seem a slight bit smoother on acceleration. I still get the message on Extreme. I guess a lift Pump is next?
It did seem to fix the message from coming up on stock setting, tow, and Performance. On Performance, it does seem a slight bit smoother on acceleration. I still get the message on Extreme. I guess a lift Pump is next?