Recent loss of power after 2k rpms

wunnabe · 10-24-2009, 09:52 AM

Well... its really starting to bug me and im trying to figure this mess out and ive gotta few ideas on hand on what it could be but i wanted to get some more opinions...

Ok.. first off i have no aftermarket parts on this truck at all.. its a stock daily driven truck with a #0 plate and Housing full forward.. Governor springs tightened down 3-clicks.. straight exhaust wiht 5" stack and an AFE pro guard stage 2 intake... it used to run like a beast all the way to 3k rpms ...and take no time what so ever getting there... well this past week i noticed i lost power above 2k rpms.. it would be really really hesitant after 2k rpms and kinda have a sputter and would put out a lil bit of white smoke... as if it was completely a cold engine that had no heat in it what so ever....

I remember from my old truck when my fuel shutoff solenoid went out that when the shut arm on the pump isnt all the way up it wouldnt get the proper amount of fuela nd have no power... well i stopped and checked it one day and all my AFC housing bolts had somehow came loose... so i tightened them all back down and that didnt solve the problem...

i tore it apart today and checked to see if the fuel plate was still forward and it was fine.. i looked and checked for leaks and found no boost leaks or anything... the only other two things i can come up with is slipping timing ( cause its cackleing alot more than it used to ) or the lift pump is dieing not putting enough fuel to the pump and whatnot... hopefully someone will chime in and give me some light on this subject... any info would great be appreciated...

Thanks.

jb 73 · 10-24-2009, 11:29 AM

Put a gauge on it, 25psi is normal. it could be that the overflow valve spring is weak...this will drop fuel psi.I would check that before i threw any parts at it. A fuel psi gauge would help you diagnose this problem.

***12VEG*** · 10-24-2009, 01:04 PM

Fuel Filter!!!

firedawg015 · 10-24-2009, 08:10 PM

I just started having the same problem about 2 weeks ago. Runs great until I get on it and want it to run above 2K then all the power is gone. Thought I had bad fuel at first because I noticed it the first time right after I filled up, but I've ran two tanks since with fuel injector cleaner and no change. I'm thinking its the fuel filter too. At least that's where I'll start.

Deeslfxr · 10-25-2009, 11:14 AM

Quote:

Originally Posted by 12VEG

Fuel Filter!!!

CumminforCummins · 10-25-2009, 12:11 PM

Quote:

Originally Posted by Deeslfxr

Another

All those problems you are saying is sounding like a fuel filter to me. Change it, use a good filter like a Wix or Fleetgaurd and get back to us on your report.

illflem · 10-25-2009, 04:34 PM

Quote:

Originally Posted by CumminforCummins

Another

Or the prefilter, lift pump or overflow valve.
Hook up a fuel pressure gauge or throw parts at it.
http://www.cumminsforum.com/forum/94...-12-valve.html

CumminforCummins · 10-25-2009, 10:01 PM

Flem always backs me up.... Hes got a point.

***12VEG*** · 10-25-2009, 11:28 PM

Any progress?

Quote:

Originally Posted by illflem

Or the prefilter, lift pump or overflow valve.
Hook up a fuel pressure gauge or throw parts at it.
http://www.cumminsforum.com/forum/94...-12-valve.html

It can easily be any of those things, but the fuel filter is the easiest, most likely, and most inexpensive part to throw.