So my truck is throwing a high rail cel and the truck back fires and cuts out. Won't rev over 1500 or 1600 rpm without spitting and popping. It also sounds like its got hard timing rattle. I removed all performance electronics and it remains. Truck ran great yesterday.

As the truck idles up naturally it smoothed out a little but if you push the gas its back to spitting and so on.

Is it the FCA or could it be something else?

 

That's EXACTLY what mine did when my RPS went bad. Rail pressure sensor, do you have a rail gauge? If your gauge works, it's not the sensor it's the FCA, if not it's the sensor.

 

Sounds like a Fuel pressure sensor to me too, Tristan did you call John??

 

that happened to my girlfriends dads 06. it actually died once too. took it to the dealer and they replaced the fuel pressure sensor. problem fixed.

 

sounds like a rail pressure sensor but i would pull the FCA and make sure its not sticking open.

 

Tristan I have an spare FCA PM sent

 

OK, im sorry...but im a dummy. What is a FCA? I see that acronym all the time, but I just plain don't know what it is. Thanks for helping out the born ignorant. Is it Fuel something something?

..

 

The rail gauge reads fine. So does that mean its the FCA. Anyway to check. I will pull it out in the morning and do like john said and spray it out. If that's not it he said I would need a new one. John is as always alot of help. Thanks for the replies guys I'll letcha know what I find.

Someone else mentioned the factory computer. What would cause a newly modded cp3 to stop workin? Like I said it ran great for 30-40 miles home???

 

fca=fuel control actuator. I think. Its bolted to the back of your cp3 (injector pump). If I understand it right iteters the fuel at the cp3.

 

also wondering with the a5k turbo I should be able to clear all that fuel and keep from getting hot. But I noticed on one of the two wot runs I did that the dgt hit 1500! Scary, that's the first time this truck has ever made it past 1300.
Is it all in the programming at this point or do i need twins to cool this down?

I plan on running the TNT software at the track but I guess I'll need to dial up my 4.11 with aftermarket inj, and turbo and seewhat happens. That is if when I finally get it all fixed.

I know I need a cam and springs still but I wonder if the twins need to be next instead?

 

If your rail gauge is working and reading accurately(while the truck is acting up), your sensor is fine. If your FCA is stuck then you should be reading some funky pressures at idle and while it's acting up. Unplug the connector from the FCA and see if your truck idles at 24000-26000psi, it should be running wide open at this point. My rail gauge was the best tool in deciding what was wrong and if your sensor is bad, the rail gauge doesn't work right.