This might not be a big desal or might be for me it was something like a feul filter problem... Biggs Eastside automotive might be able to help you out give them a call and ask them about it...
Monday - Friday:
7:30 am - 6:00 pm
Worst case scenario it may need a valve job.....$1200-$2000. Less if you DIY. If it truely needs a valve job, then the current ebay bid price is already way too high. There's some rust on that truck too.
You can find 99 D1's for around $6k if you look hard enough.