NVW
Well-Known Member
My 98 has run perfect for three years, the gfi tripped at -30C a few times and it fired up with little smoke. I know it tripped when the timer cut in.
This spring it smoked grey for a second then would clear up, it started to buck at certain speeds but would run perfect at others, I suspected the APP, changed out with no luck. It started to get much worse so I thought maybe bad fuel or a plugged filter. I opened the water drain and got a bunch of wax out of it, likely Biodiesel.
First off I changed the fuel filter. blew back into the tank and took off the IP fuel inlet and made sure the screen was clear, still no good. The truck would run but smoke grey and would accelerate at low rpms, if you stepped on it it would just rev to 2000-2500 rpm and not upshift.
I tried known good PMD's with no luck, I pulled an OS off an engine that is on my engine stand that was running well and changed it out, no go. It was progressively getting worse, then sometimes it ran almost normal with good acceleration. I then took the CPS off the spare engine with still no luck, but the smoke was pretty much gone with smooth running. It will only rev to 1000 to 1500 rpms, it varies every time I run it. I next tried the ecm from the donor truck, still no change. It idles well but will not rev up, I'm thinking the armature or something in the IP is effed. It has had an occasional fishbite since I rebuilt it. It is the IP that came with this truck

This spring it smoked grey for a second then would clear up, it started to buck at certain speeds but would run perfect at others, I suspected the APP, changed out with no luck. It started to get much worse so I thought maybe bad fuel or a plugged filter. I opened the water drain and got a bunch of wax out of it, likely Biodiesel.
First off I changed the fuel filter. blew back into the tank and took off the IP fuel inlet and made sure the screen was clear, still no good. The truck would run but smoke grey and would accelerate at low rpms, if you stepped on it it would just rev to 2000-2500 rpm and not upshift.
I tried known good PMD's with no luck, I pulled an OS off an engine that is on my engine stand that was running well and changed it out, no go. It was progressively getting worse, then sometimes it ran almost normal with good acceleration. I then took the CPS off the spare engine with still no luck, but the smoke was pretty much gone with smooth running. It will only rev to 1000 to 1500 rpms, it varies every time I run it. I next tried the ecm from the donor truck, still no change. It idles well but will not rev up, I'm thinking the armature or something in the IP is effed. It has had an occasional fishbite since I rebuilt it. It is the IP that came with this truck
