Tuf-4x4

This is the second time in the shop in the past week. Here the story Im in hot shot buisness and I drive all 48 states. At the time of my first ordeal I was towing 20,100Lbs from Montana to New Mexico. I had a 12cyl Cummins on my 40ft trailer. Once I got into New Mexico the truck started missing so it seems. It almost feels like when you hit the rev limiter on a gas car and it jerks back. I took it to the dealer ship and they told me I had bad fuel and the there was debrey in the filter bowl. They sharged me 250 to flush the system and what not. From what I could tell the only thing they did was give me a new air and fuel filter. Now 300 miles later its happening again but it feels worse. What do you all think it could be. It can't be that I got bad fuel once more. ANy info would be great thanks.

drewblood

any codes sounds like possibly the turbo might be surging anything going on while monitoring boost does it idle rough

53 willys

key "on" key "off" 3x, leave it "on" on the 3rd and watch the odometer for codes.....then tell us if you have any, what they are

Dodgezilla

Anytime I have a performance issue the first thing I do is pull the fueling boxes/downloaders off the truck to see if that is causing the problem. Every issue I have had with this truck has been caused by my aftermarket stuff....

Tuf-4x4

THe down loader has been off the truck since I had my first problem. There are no codes. IT does not idel rough but when Im driving in the lower rpm rang it sputers pretty bad. I can smell fuel when its ideling though.

trik396

May be a chance you have some fuel leaking from the high pressure lines after the cp3. I had a fuel leak, smelled diesel. Thought it was the cp3 leaking until I followed the leak all the way up to the rail. Several of the tubing nuts holding the injector lines to the rail were leaking. They were barely hand tight. I snugged them up VERY lightly and haven't had a problem since. This was when the truck was pretty new. NEVER work on these lines with the truck running. Death or dismemberment can occur. Just wanted to warn ya..

John Halter

I would change the fuel filter again , you may have still had some bad fuel in the tank and toasted the new one . Smelling fuel could mean air is getting in the system some were , which would cause a similar response from the engine . Since the problem went away after a filter change for a while and then came back that is were I would start . Wish I could help more but that is the best I can come up with , good luck .

Tuf-4x4

Thanks John for the info I will call the tech and let him know of this. Oh trick396 thanks for the heads up on the harm that can be done with pressure on the lines.

cquestad

Relief valve?

jwb600

is your rig a 5.9 or 6.7?

Tuf-4x4

its a 5.9. Relief Valve?

trik396

They do go bad but you wouldn't be leaking fuel from it where you could smell it... Have you gotten under the hood and looked for fuel?

Tuf-4x4

Yes sir, theres no fuel leak. Hell the tech dose not know whats going on as of now.

53 willys

if it is a relief valve then you would have zero leaks..when it blows it feeds the fuel straight to the fuel return line..so you dont have fuel spraying all over the place.....

it should set a code if the RV blows right??

cquestad

I have blown up a RV so bad...that soooo much fuel was going down the return line...with more pressure than the slip on fittings could handle...gallons and gallons of fuel everywhere...so it can happen either way.

When my mind clears up...maybe I will have something better to add....