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Docfranco
05-18-2005, 12:32
Hi all
I have just mostly finished a swap of a 1996 6.5 TD into a 1980 scout. Now that i am driving it I am experiancing a strange miss. It idles fine, fires up great, revs nice. But while driving it has a irregular miss, only in mid throttle. no miss under acceleration or if i stop it stilll idles without a skip. it feels like a spark plug shorting out. i have not yet run codes, i will later today. two days ago I did find algae in the tank & had to drop the tank & clean it out then had a no start incident & found code P0251 which at this point i attribute to the fresh fuel system cleanout. I am already running a remote FSD. the pump is a 5521. Is this an indication the IP is going bad, or am i missing something else?

charliepeterson
05-18-2005, 18:44
This Injection Pump needs lots of fuel. Do you have a lift pump to force feed the Injection Pump. The Injection Pump is capable of pulling from the tank on its own but performs much better with some help. 3-5 psi is all you need under a load.

Docfranco
05-18-2005, 20:34
afirmative, i am running the AC delco OEM new fuel pump.

Hubert
05-19-2005, 05:41
Hmmmm would you call it a fishbite (small brim or pan fish not a lunker bass) type feeling.

I get a little bit of it and have read several other with similar feeling too. Mostly at about 1700 rpm light load. I can't feel it at 2000 + RPM.

I think its the way these engines meter fuel. Fly by wire throttle electronic pump etc. You have covered PMD/IP already. So ....

I am not sure about worn injectors mine have 120k miles and I want to change them but can't afford it right now. Any comments guys?

My clutch also just took a hike and I think I felt it bumping a little more limping it home easy. I guess the something in the springs in the disc absorbing the diesel vibration powerstroke surge etc. What is your flywheel/tranny set up?

rjwest
05-19-2005, 12:41
Slight miss at low rpm with TCC locked , light load.

Had it for a year, finally IP started to die when warming up .
Replaced IP , fixed " Fishbite"