eb290

Has anyone had a problem when they removed the fuel rail pop off and put a plug in it. Anyone blown up the fuel rail. I'm running stock power. The over pressure valve has popped off to many times and now I have low rail pressure. Also have the EGT light on.

cbrahs

the rail is not the problem when capping it off. its the injectors. Don M has posted some good info on capping them off in the 5.9 section and the reasons not too cap them off. with the 6.7 and the cost of injectors, I would not run the risk. I know there is a company out there that if you send in your psi relief valve, they will rebuild it and shim it so it pops at a higher psi but still pops to prevent injector tip cracking and other injector damange.



on edit- here is the link. lots of reading but worth it. https://www.dieseltruckresource.com/...k-t257963.html

eb290

Thanks, that is just the information I needed. I can get a pressure relief valve for $190 + shipping if it pops again. That is a heck of a lot less than what a injector costs.

cbrahs

i would get the one for $190, ship your old one out to get rebuilt with higher pop settings and keep that one stashed for future use. then no downtime other than changing it out

dodgeram082500

I agree with cbrahs we 190 dollars is cheap compared to what a single injector would cost. We shimmed mine with the mp8 install and had no problems with it popping thus far.

Kylemm1002

Ive had mine plugged for 20k miles with no problems at all.

From what I understand (unless tested) once the valve is shimmed by a regular 'kit' it raises the pop off pressure so high that by the time it opened the damage as already been done.

Im also pretty sure the factory vlave has a 'usable life' Once it opens more then say 10 times its junk and needs to be replaced. I hoooked mine to a scan tool and it showed it opened like 80 something times, Hooked the same scanner up to my buddies low milage truck and his read 0!!! Almost could not believe it

But if your right $200 now is better then $4000 later!

Mike Holmen

Your CP3 will also cut pressure to regulate pressure. So really your not increasing rail pressure to much. If you start to run bigger injector nozzles, you might need to shim the pressure relief.

rdneckn

I have found that one of the problems that cause the high pressure relief valve to dump it the (EFC) Electonric Fuel control valve. This Valve controls the fuel pump. If you are having real problems with the valve you need to look at this. I have seen to meany Cummins engine at work with this problem and 8 out of 10 need the EFC replaced.

Mike Holmen

The shim reduces the amount fuel draining back to the tank. If you run bigger injector, you probably need it. As for CP3 stuff its call the bag of parts, can add 10-15% to an existing CP3. Just don't cap the rail, your asking for issues.
http://www.motorsportdiesel.com/stor...pt-270406.aspx

jlambert

My 08 2500 w/auto trans has gotten to the point that it pops the valve almost every time I pull my 5th wheel. After a day or so it resets, only to pop again next time I tow.

There seems to be some disagreement as to whether it is safe to shim this valve. Some say it's almost as risky as using a rail plug. What do you guys think?

Also, if I decide to replace the valve is it a Mopar part or can I save some money and get it from the local Cummins dealer?

Thanks all for the help.

ER-74

Jlambert, I have the same issue as you. I cant tow my 24' trailer without getting the low fuel pressure rail light on. Also I noticed that my rail pressure is no more than 23,000. Any advice help will be appreciated.

jlambert

I haven't really gotten an answer one way or the other. I think I'm going to buy a replacement from Dodge and install it when I'm under the hood doing my deletes. I also plan to buy the shim kit for $15. It comes with 3 shim washers. If the new relief plug starts to give me trouble I will probably install the shims one at a time in the spare and see what happens. Other nthan that I'm open to any ideas.

mega-engr

This is a safety valve, and anytime a safety is activated then I'd take a good look at why as opposed to "putting in a larger fuse" so to speak. Yes, there could be an issue with the valve itself I suppose, but I would also take a good look at the root cause. Pressure is restriction to flow. So, something is causing too much flow for a given restriction or there is some restriction going on for a given flow. I think someone here posted on a fuel control as a cause.

jlambert

1) Where is the ecv located?

2) What is the exact name for this part? I can't seem to find it when doing a parts search.

3) What is the correct name for the pressure relief valve. Again, it does not come up when doing a parts search. I'm looking on dodgepartsmopar.com.

4) Can the dealer diagnose this even if the valve has reset and the cel has gone off?

5) Can us lowly civilians buy a service manual for the 6.7 from the dealer or is there a better source?

I know this is a bunch of questions... I appreciate any help you guys can provide. Thanks much!

jlambert

Where did you find the pressure relief valve for $190? Thanks.