Hey all,

First off, my truck is an 05, 16000 miles, new fuel filter at 15,000. BDDL, Q-zilla Commander, in line lift pump.
Went to start my truck yesterday and it didn't want to start right. Cranked like normal, started up, idled very rough, then died. Ran fine just 2 days before. I tried it again but gassed it when it got rough, it idled up like normal, then fell sharply so I let off the throttle. Idled rough again so I gassed it again and held it to 1500-1800 rpm for a bit. Let off and idled normal. My dad drove it last night, said it died on him going around a sharp corner by his house. He got it back to me today and it now sounds as if it's idling on 4 cylinders. Rail pressures at idle are 20000 psi or thereabouts. What could be causing such high pressures at idle? Any ideas?

 

As an update, I cleaned the COV. Didn't help with my rail pressure problem, still 20500psi at start up... truck used to be 6500-7000 at idle. My logic would say that for some reason I don't understand my rail pressure relief valve isn't working. Tried to take it off to check, but the valve itself is on there very very tight and I have limited tools at work. Any opinions?

 

try taking the Quad off first it taps into the rail sensor if it helps I say maybe a bad harness DO NOT RUN IT with that high of rail psi you WILL kill your injecters.If it does not help I would start looking at the rail senser or the fca being bad

 

Thanks for the reply. I don't want to sound argumentative (i'm not trying to be) but I am curious why you say 20500 will damage injectors? I've seen a diablosport power puck go to rail pressures of 22500+. Even a quad xzt will go above 20,000. Neither stay there all day though.

 

true is will go to 22500+ but for how long? a few seconds.so if you idle the truck for 3 minutes at 20500 what is harder on them???

 

Also could be the regulator on the cp3 pump has gone bad or just came unpluged. worth checking out anyway.