6.2 diesel driveability issue - feels like "flooding" when accelerating

[biggerhammertx]

Hello All,

I have an 1993 Ex-Navy GMC k2500 4x4 that has recently started giving me drive-abilty problems.

When I accelerate at moderate speed / throttle settings, the motor sort of goes "flat" and doesn't want to accelerate, in fact if I had to name the feeling, it feels like a gas motor does when it is "flooding" out.

If I stab the gas pedal hard, I can get over the 'sag' and get it back up and running at higher speed, but if I don't get on it quickly when it starts to 'sag', it will often just quit.

Any ideas of what to check out? 6.2 Diesel, 41K miles,

I've topped up the tank twice on the assumption that maybe I had some bad diesel. No water in fuel light. Just not sure what to check... Fuel Filters, Pumps, injectors, or ??

Thank to any and all for your insight or help.

BIGGERHAMMERTX

 

[Captaincarrier]

Injector pump......

 

[CUCVLOVER]

Fuel filter, lift pump, injection pump.
Being a 93 that motor is probably covered in wires but still should be a basic 6.2

 

[Barrman]

That is the same basic engine with the same basic support components as the CUCV trucks. The -20 manual has a great troubleshooting section on drivability issues.

Basically, change your fuel filter, check your lift pump flow, check your air filter and then you get to the things which will cost some money. Do the basics and if they don't help, you really aren't out anything because it was preventative maintenance that needed to be done anyway.

If they don't help, pull the return line check valve on the top of the IP. Look inside. There should be a glass ball in there. Look into it and see if things are clear. Clean it out either way and make sure the ball moves when you push on it. If clear, one more thing serviced. If gummed up then IP issues are in your future. You can knock the ball out to give a few more miles of running, but that is almost always a dying IP indicator.

 

[CUCVLOVER]

That is the same basic engine with the same basic support components as the CUCV trucks. The -20 manual has a great troubleshooting section on drivability issues.

Basically, change your fuel filter, check your lift pump flow, check your air filter and then you get to the things which will cost some money. Do the basics and if they don't help, you really aren't out anything because it was preventative maintenance that needed to be done anyway.

If they don't help, pull the return line check valve on the top of the IP. Look inside. There should be a glass ball in there. Look into it and see if things are clear. Clean it out either way and make sure the ball moves when you push on it. If clear, one more thing serviced. If gummed up then IP issues are in your future. You can knock the ball out to give a few more miles of running, but that is almost always a dying IP indicator.

When the ip went on my truck the valve was plugged and full of trash. Cleaned it and got a little more life but it showed me the pump was dead.
Good advice barrman

 

[cucvrus]

In Pennsylvania. We put the trash out by the curb every Friday and a man/men come in a big loud diesel truck with a compacter and pick it up. Do you try to recycle it in your fuel tank? Interesting. Do they have big trucks like that down by the river?Happy Holidays. How's the canoe Rental business?

 

[CUCVLOVER]

In Pennsylvania. We put the trash out by the curb every Friday and a man/men come in a big loud diesel truck with a compacter and pick it up. Do you try to recycle it in your fuel tank? Interesting. Do they have big trucks like that down by the river?View attachment 656386Happy Holidays. How's the canoe Rental business?

https://jet.com/product/detail/2209...M99beSIzwz0b2wo5fgfa7BoCyuvw_wcB&gclsrc=aw.ds
I use this

Rentals have slowed down with the cold weather. Happy holidays to you to buddy