MAC702

My brother changed out my fuel filter, which it needed. But now it won't idle well. It idles better after we bleed the filter, the IP, and the lines at the injectors. But it still loses prime after a couple hours.

Should we suspect the lift pump? Brother says it was starting to run poorly, which is why he suspected the fuel filter in the first place.

Seems something always go wrong on the truck when my brother borrows it, of course.

Assuming the lift pump is the culprit, is it best to replace or upgrade?

gorms

I'd check the fuel filter first. I needed one quick a few months back and could only get a cheap one from auto zone, one of the o-rings (the small one) was defective and had a split in it after a week, had similar symptoms to yours. If you can, check the lines by pressurizing the fuel tank with compressed air, only a few pounds should show you any leaks.