this morning the truck would not start it would fire and die right away, did that like 5 times and the 6th time it started. Ran ok but rail preasure was all over the place jumping up and down. So I unpluged the ts preasure box and quad rail gauge and no change. this afternoon got ahold of a scaner and did some more troble shooting. when truck is cold runs perfect, when up to running temp runs bad. lots of injuctor noise. and dose not idle good at all. It idles like it has a great big cam, like a drag car. Idles up falls on it's face, Idles up Falls on its face. when idles up like steping on throttle quick and letting off and blowen black smoke. and injectors sounding like they are going to explode. it is mind boggleing. One guy says it is the Fass pump has to high of preasure and took out the regulator. and I have a nother sug that an injector is bad. truck is not giving any codes either. I do not know like I said runs good when cold and bad when at running temp???

any tips would help greatly.

thanks.

Justin

 

Like this? http://s4.photobucket.com/albums/y10...MOV00340-1.flv

 

injectors, unfortunately

 

The lack of punctuation and run on sentences drive me nuts. This makes threads difficult to read....

 

That vid is crazy!!!!!!! Mine started pinging and popping like the vid saturday when leaving lake. Pulled over and took quad box off and it went away. It was weird for sure!

 

That vid is just like my truck, but has to be at running temp to do that.

 

I put the truck back to stock program and still the same as the vid. so it is not programing. I am thinking cracked injector, when at running temp it expands and lets more fuel in, then it runs crappy!!!!!

 

The truck in the video needed a new rail pressure sensor. A sticking FCA or a rail pressure sensor will do that to a Cummins. Do you have anyone around you with a common rail engine you may be able to borrow parts from to help diagnose the issue? FCA's are pretty cheap but I think the rail sensor is around 400$. What does the quad rail gauge say when it is hooked up?

 

I unhooked that cuz I thought that the gauge was messing it up, but I had the scanner on it. The Rail preasure would go up to 9,350 psi at idle then back down to around 5,000 when at idle. The preasure would move around like that when truck got to running temp. also did an injector test when I disabled 1 and 6 it realy did not run that diff. You could tell when 2,3,4,5 were not working.

 

Personally I would look at the rail pressure sensor before ripping out the injectors. The sensors can sometimes not throw codes as long as the error is within its specs. In other words, the ECM looks for a open circuit or a grounded circuit to cause a DTC. There have been many people that have had the same kind of stuff going on as you and a rail pressure sensor fixed it. Have you checked your oil for fuel yet? You may find it silly but if you cant smell it you can always taste a tiny bit of oil to see. Fuel has a bitter taste, very distinctive and antifreeze is sweet. I do it all the time at work when you dont have time for a oil sample to come back.

 

I will check the oil, I know a guy with a extra rail pressure sensor. I will put that in and see if it helps or not. Do you think having the quad preassure gauge on it would some how damadge that sensor, or ts preasure box??

 

I dont think that a pressure box could cause the sensor to fail but... everyone on here with a failed sensor that I know of had some kind of box or programmer. There really is no way for the box to put excessive voltage to the sensor. I know my MP-8 is fed by the 5v supply so its not like it could short out and send 12v to the 5v sensor. I will continue to use a pressure box even if I have a failed rail pressure sensor. I dont see where the box could fry the sensor. Try that other rail sensor and let us know if it fixes it. If that doesnt work I would try to swap over his FCA too just to make sure but I think the rail sensor will fix your issues.

 

thanks for the info, Now I am just trying to get ahold of the guy about that sensor. I just went for a drive ( the truck was cold) ran fine and when got to running temp problems came back rail preasure all over. Now will not run. If I just turn the key on the rail preasure is at 26,000. Has to be that sensor.

 

Just got back from a test drive with the New (used) Rail Preasure Sensor, and it work perfect! It seems to build boost quicker and I have 4 lbs more boost. I think I am going to get a spare and keep in the truck just incase!
I am kind of scared to plug in the quad rail gauge becouse I don't know if that is the reason if why it went out in the first place??

Thank you matego for the info!!