loss of power when towing

[Gene888]

96 k3500 CC LB Dually 6.5
I am by no means a gear head, but am confident to tackle most jobs.
Recently did....upper and lower balls joint, tie rod ends, front rotors, calipers hoses, fuel filter

Bought this truck used, dont know any real history.
Picked up a 20' 6800lb gooseneck trailer and the truck struggled to get up hills. Hard time keeping speed at 65mph. Got a P0326 code. Service engine light went out on its own. Didnt notice nay broken/cracked vacuum lines to turbo. Have recently replaced the fuel filter. Read here that there is an inline Injector Pump filter (not sure where to locate it). Any insight would be greatly appreciated.

[BrentN]

That code isnt listed in the DTC list. Not sure what it is.
Go here for the codes for 96+ vehicles
http://www.thedieselpage.com/members/DTC9698.htm

The inline filter is on the inlet side of the injection pump. As you are facing the engine, it is the hose that is on the right most top side of the injection pump. Remove the hose and then use a deep socket (I think it was a 15mm., try and see).

The inline screen/filter is a complete assembly. Move to cleaning it out really good.

Aside from checking all of your filters (Simple things first), getting gauges is another good step to see how your turbo is working (Boost and Pyro).

If your vacuum pump is intermittent, you may be losing boost, but it will set a code if boost is too low.

[DennisG01]

Are you sure it wasn't 236, instead of 326? 236 is a common one (low boost) associated with either cracked lines (which you said you addressed) or a failing wastegate solenoid. I wasn't aware that that one would cause a defuel, but I am not an expert. If it was a 238 (high boost), now, that I can tell you that it WILL cause a defuel (experience).

[Gene888]

oooppps....was a 236 code. Will check the inline filter.

Just a side note, truck seems to generally lack pick up, no real get up and go when gas pedal is depressed.

Will check back in after I clean the filter tomorrow after work. Thanks guys!

[a5150nut]

oooppps....was a 236 code. Will check the inline filter.

Just a side note, truck seems to generally lack pick up, no real get up and go when gas pedal is depressed.

Will check back in after I clean the filter tomorrow after work. Thanks guys!


Well theres your problem right there! You got a gas pedal in a diesel, happens every time!:D

[DennisG01]

Just a side note, truck seems to generally lack pick up, no real get up and go when gas pedal is depressed.


Just out of curiosity, what are you comparing that to? Is this your first time with an older style diesel? A 350 gasser will definitely out run a regular 6.5. the 6.5 doesn't have nearly the immediate "get up and go" that a gasser has, but the gasser will require a lot more gas pedal to get a load going than the 6.5 requires.

All that being said, I am VERY happy that I have a 6.5 in my Suburban as opposed to a 350 or even a 454. The 454 would likely be about the same as far as pulling power goes, but it won't even come close to matching the mileage.

FYI, a new ECM (computer) tune will fix that lazy pedal!

[Kennedy]

Start with a 15 psi boost gauge and pyrometer. This will provide meaningful data to help troubleshoot any issues you may be having.

[Gene888]

@ DennisG01 .... First time for a diesel period. Needed it for my contracting business to tow a gooseneck.

@ BrentN ..... I could use some more guideness on locating the IP and this filter. I am not quite sure what I am looking for, learning as I go.

@ Kennedy .... Gauges are in the near future, as well as an exhaust from you (I previously emailed you about the exhaust with a cat). I am definitely interested in both, but need to wait a very short while since I just moved to a new state and started my contracting business back up.

Thanks to you both for the help and input

[phantom309]

hook a spring on the wastegate actuator to keep it closed,. drive it,.
if it suddenly wakes up,( and then codes a high boost condition).buy the boost guage,.and build/buy your own turbomaster thingy,.(check engine light comes on for high boost,. motor cuts back power, cycle the key on and off it resets,.
put a new fuel filter in it, the black can looking thingy at the back of the intake,.(the one at the I njection Pump is usually clean)
make sure you actually have fuel pressure,.;)..... fuel pumps(technically called a transfer pump) can give up,.(under driver side, on inside frame rail,.they can make noise and make no pressure or volume,..) and the injection pump (where all the lines come out of) will still draw enough fuel to run, but the motor will be weak,.
lots of stuff on youtube for visuals,.
JM2C

Nick
ps my 6.5 can keep up with any 350 tbi :D