94 6.5TD 4x4 4L80E,, Truck started idling rough, pulled codes 97 & 98, cylinder balance fault. I can hear a noise that seems to be coming from the intake, it gets louder if I open the air filter housing and listen through the turbo. Any ideas on whats going on here?
One more thing, I just had the trans re-built. Could the trans shop have messed something up on rear cylinders on both banks? Can't imagine both head gaskets going at the same time. Or a problem on 7 & 8 showing up at the same time either. This seems weird.
Ted

Seems to have been an easy fix. I had a new fuel filter here and thought what the heck.. Old one was in about 15,000 miles and looked pretty black. Replaced filter and fired it up. Smooth idle and after clearing codes they did not come back.. Thanks to all the techs who responded to similar problems in the past, I looked at them all and figured fuel delivery, if I was lucky.
After the trans shop buggered up the trans install, I guess I'm pretty quick to think they might have messed up something else while they were buggering away.
Ted

Damn, Drove the truck 800 miles yesterday and it ran great. Fire it up this morning and the engine is shaking all over. Pulled codes 91 and 98 this time. This is getting weird.
Help !!!!!
Ted

Cleaned connector plug and big wire connectors on glow plug relay, cleared codes, fired it up. Runs good again, no codes. Hmmmmmm.
Ted

Last few days it has done it again. Code 98 comes up most along with a 97 or 91, was a 91 by itself once. Weird. Got new glow plugs coming. Seems it happens only when I start it after it sits all night. It will run with no fire in a cylinder or two so I let it warm a bit, clear codes then start again. Usually fires up and runs fine after it gets a bit warm. Then all day with quite a few stops and re-starts it runs fine.
I can't believe nobody on here has an opinion on this.
Ted

injection pump or injectors

Patrick, That sounds simple enough, but what is your reasoning?? I'm going to change glow plugs first and see what happens. I can see wore out injectors causing it, but the truck runs great after it gets fire in all 8 holes. Fuel mileage is pretty good too. 18 mpg.
Ted