stone stock '06 and thru a 0191 code last night

[2broke2smoke]

did a search and read a post that stated "dodge is aware and it's a glitch"



read another that stated dealer switched out pop off valve and now truck has white smoke at start up ...



any thoughts or updates ...



truck runs perfect and i plan on seeing how long it takes for the cel to shut off ...

 

[CDonaldson]

I had the 0191 code right around 2K, went in to the dealer, they cleared it, claimed no trouble found - computer glitch. The tech told me that for whatever reason about 1/2 the trucks he's seen throw this code, once cleared it never comes back again. Not so - mine did it a second time, took quite a few startups to clear itself. From all that I have read, that code has to do with low rail pressure. I became concerned about it more the second time because I think a chronic low pressure to the rail speaks loudly about supply/demand problems with the CP3 or a current problem with the relief valve sticking open or functioning slowly. Since we seem to run normal with a low fuel pressure of 6-8 and at WOT we can be at 0, this does not quite cut it regarding pressure. Obviously volume is minimally sufficient, but it is at that point when you throw the code. I installed a fuel pressure gauge to monitor the situation, have a rail pressure gauge (due to arrive today) for more monitoring. I picked up the kit to eliminate the valve just in case I had a problem on the road with it sticking open and not closing, could at least get it home without having a tow to the dealer to install a new relief valve. That scenario has already been experienced by many, and more than once I might add. So, no real update, but at least an idea of how to deal with it in the meantime. I hate to just install the kit and be done with the relief valve problem. I has been suggested that might bring on a whole new set of problems. Someone here or on another site is working on a mod, or another valve, or something? Maybe they will chime in regarding this. I have not had the problem again, and have not been able to duplicate it again, but at least I am prepared.



CD

 

[fireman717]

I had the same code after about 1000 miles on the truck was snowing outside. Reset and has not happened again 9400 miles now.

 

[Axion]

I was wondering where the fuel pressure and rail pressure sensors go on these trucks? I have seen an adapter for the top of the fuel filter and a hollowed out banjo bolt on the CP3 from Geno's Garage. Are these the most common spots? I am just trying to decide what I need to monitor without making my truck look like an airplane cockpit!



Was also wondering where you got the kit to eliminate the relief valve from CDonaldson?

 

[KVoigt]

I hope I am not asking a stupid ?, but how do you tell it through a code? Do you guys have a programmer or something to tell? thanks

 

[TAbbott]

did a search and read a post that stated "dodge is aware and it's a glitch"



read another that stated dealer switched out pop off valve and now truck has white smoke at start up ...



any thoughts or updates ...



truck runs perfect and i plan on seeing how long it takes for the cel to shut off ...

I had the same P0191 code and took it to Carson Dodge in Carson City. They cleared it and said it was caused by turning the key on and leaving it on too long prior to starting the truck. The compututer starts looking for rail pressure and finds none, throwing a code. So, if you are waiting for the wait to start light to go out and your cell phone rings and you don't start the truck before answering the phone, you're gonna get that code according to them. They also say it should clear itself over time or a certain number of starts. Mine did not prior to taking it to the dealer.

 

[CDonaldson]

I got my kit from Diesel Power - you can PM him here on this site. C/O the thread on rail pressure group buy - which is the gauge, but he can also get the kit. Some just pull out the relief valve and plug it, the kit has a much better setup. I believe he is the one also looking into a modded aftermarket relief valve?



I suppose it is possible to have the code come up due to the key on - but when you read the circuit information in the repair manual both the high and low rail pressure codes should only be energised/involved after the engine is running, or at least that's how the circuit is designed to function. There have been several different speculated scnerios that could cause this code to throw - all I know is it IS an indication of LOW rail pressure and if true, this could lead to a host of other problems.



CD

 

[2broke2smoke]

I hope I am not asking a stupid ?, but how do you tell it through a code? Do you guys have a programmer or something to tell? thanks

check engine light came on ...



just cycle the key on and off three times and watch your odometer ...



Tabbott, i'll check with the boss, it's her truck ... she works out of it daily so it's a good possibility something like that happend ...

 

[Heavy Metal]

I had the same P0191 code and took it to Carson Dodge in Carson City. They cleared it and said it was caused by turning the key on and leaving it on too long prior to starting the truck. The compututer starts looking for rail pressure and finds none, throwing a code. So, if you are waiting for the wait to start light to go out and your cell phone rings and you don't start the truck before answering the phone, you're gonna get that code according to them. They also say it should clear itself over time or a certain number of starts. Mine did not prior to taking it to the dealer.

I had mine in a couple of days ago for a CEL at 5100 miles and the service manager told me the tech. found (and cleared) code P0199-low rail pressure. After reading this thread, I'd bet good money that it was actually P0191. I was in my truck getting ready to go to work that morning when I realized that I left my cell phone inside on the charger. Got back to the truck and noticed that I left the key in the "on" position. When I started the truck the CEL was on and stayed on until the dealer cleared it.