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View Full Version : 98 burban having problems



danballa
01-16-2007, 19:48
Hey there everyone. This seems to be a great site, and hopefully, can help me find out whats wrong. I've been reading for a couple days, but I'm still not real sure what I'm up against.

I have a 98 6.5t suburban (107,000). I've been fighting some problems since early summer. Shop replaced the lift pump then..and a few thousand miles, it started acting up again. This time they said there was air in the lines, bled it out, and it seemed to work well for another thousand or so miles, now it's having some more problems. They said I should try to bleed air out again. Which I plan on trying again, in the morning during the daylight. Quick question on that too..i have the instructions, but it says to pull the fuel/sol fuse..only there is no fuse there. ? ..I see the relay there, and read something about jumping it...but dunno about that. Also, and tips or anything to help cut down on the smell of the inevitable diesel I'm going to be inhaling? I'm migraine prone, and can't be around the smell for long at all.

anyways, on to what the burban is doing. I let it set and run in my driveway, for 45 min..ran without any problems...oh course. I took it on the road..less the 2 miles later, it started to surge a little..the first warning signs for me to turn around. with a mile or so of the first surge..it will usually start bucking, and losing power. Then it will start to lose power..hard to go the speed limit..drop below the speed limit. If I try and give it more gas, it bogs down. Runs real rough, jerking and such..having a rough time to idle, but generally will not actually die. Occasionally it will..but I'm usually to a "safeish" spot, and shut her down myself. It will fire right back up, rough idle, hard to rev. I can let it set 20-30 min, then it will start up..idle fine, rev fine, and drive fine for a couple miles, and then we go through the entire process again untill I am home. Let it set over night, and the next morning, always fires right up..even below freezing.

Does this sound like air problems? From what I've been reading the past few days, I'm leaning towards the PMD.

while i'm here..I've seen people put links in posts..I click on them..asks for user name, password..But mine doesn't seem to work, and I can't follow the link? Do I need to do something else?

Thanks for any, and all help, tips, suggestions.

Bnave95
01-17-2007, 07:33
When this starts doing the loss of power. Pull fuel cap off tank and see how the cap acts. Does it seem to want to hang on? Vaccum. Run with cap lose,problem returns?
With these issue the SES should be on in the dash or even flash.
Do you know how many miles are on the pump? PMD maybe?
If you question that air may be getting into system than you can take the return line off of the inj. pump. Top front of pump. short tube going to metal return down close to the T-stats. Replacing the tube with a clear line and when running you will be able to see air bubbles passing through if you have air in the system. Air can only inter before fuel lift pump. Bad injectors can also have the same effect with allowing air in. This does not sound like your problem.
You have a new lift pump,what happen when you open the water drain valve?
Eng. should not stall.
Also you should not have to bleed the fuel system other than during fuel filter change.