injection pump on its last leg?

[HANK1948]

About a month ago it started stalling at idle but it ran great going down the road, so i changed the fuel fiter and raised the idle up a bunch (for winter) and that seemed to do the trick. but yesterday it started stalling again with the idle still high . it seems to surge a couple of times at idle then stall, also after it stalls and it starts right back up I will go to take off and it wont take off right away it takes a few seconds then it goes like hell. But when iam crusing it runs fine. I also changed the fuel filter again just incase but that didnt change anything. help! by the way this is a 88 6.2 3/4 ton burb 200K :confused:

[britannic]

Check for air leaks in the fuel lines up to the lift pump before you write the pump off. Pressurize the fuel tank with about 8-10psi of air (using a tire valve in a spare fuel cap) and then check for seepage in the lines over the next 30 minutes or so.

[HANK1948]

will all DB2 pumps work? on my 6.2

[britannic]

Yes, with the caveat that there will be variations in dynamic timing advance and total fuel injected depending on the model and year.

[Peter J. Bierman]

How, hang on for a sec!

All GM DB2's will work, not any....
Ford used the same pump but its setup to rotate the other way around.

Peter

[dieselbegreat]

Hank: Mine did the same thing you described last winter for about two or three weeks, then cleared up. I think the housing pressure was all goofed up because of air leak in the fuel line (which I re-tightened some clamps) and dirty or stuck valve in the injection pump. Yours may clear up on its own if you can live with it in the meantime. Check for air leaks, wet and/or rusted lines back by the rear axle, though.

[britannic]

Originally posted by Peter J. Bierman:
How, hang on for a sec!

All GM DB2's will work, not any....
Ford used the same pump but its setup to rotate the other way around.

Peter Nicely spotted Peter, I shouldn't have assumed the question was restricted to GM pumps.

To underscore your point, I saw a DB2 4 cylinder pump on a John Deere tractor the other day.

[HANK1948]

bad injectors wouldnt give me this problem would they? also I always run power service in every tank full. Thanks for all the info guys!

[britannic]

Do you have a mechanical pump or DS4? If you do have a DS4 your symptoms take on a whole new realm of possibilities and I would recommend reposting this topic in the 6.5LTD section.

[Peter J. Bierman]

How about the lift pump, does it work ok?
If it getting weak, it might not give enough fuel at low rpm and still do ok at cruise.

Peter

[N9Phil]

I would suspect an injector might be causing your problem. I have run into the same problem several times with my Iveco Turbo Diesel. After giving it a double or triple dose of injector cleaner, the idle always smoothes out.

N9Phil

[HANK1948]

Originally posted by britannic:
Do you have a mechanical pump or DS4? If you do have a DS4 your symptoms take on a whole new realm of possibilities and I would recommend reposting this topic in the 6.5LTD section. Britannic , this problem is on my 88 6.2 burban. I also did what you said and pressurized the tank and found no leaks. I noticed when I free rev it, the rpms dont come up for a couple seconds then the motor reponds, but still runs fine driving down the road :confused:

[HANK1948]

I forgot, also were is the lift pump located. I believe on the 6.5's its located along the frame but I know its not on my burban the only thing I see is a pump on the side of the block that looks like a fuel pump , is that called a lift pump on a diesel?

[britannic]

On your mech. 6.2L, that pump is the lift pump, you need at least 5psi from it for the IP to work properly.

[HANK1948]

I replaced the lift pump today, still shutters and stalls It doesnt smoke much, only on start up ,so I believe its not the injectors? so I guess its the injector pump? Iam at a loss:confused:

[britannic]

Originally posted by HANK1948:
I replaced the lift pump today, still shutters and stalls It doesnt smoke much, only on start up ,so I believe its not the injectors? so I guess its the injector pump? Iam at a loss:confused: Talk to Tim Wagner at www.accuratediesel.com (http://www.accuratediesel.com) about your pump, mention you're a DP member:

Accurate Technical Services, LLC
8768 N Centerline Rd.
Bitely, MI 49309
(231) 598-1227