what is up with this thing
 

It cuts out at high rpms low rpms whenever it feels like it check this vid out http://s28.photobucket.com/albums/c2...t=MOV01023.flv it shows it in it's finest.:booo:

i'm taking a stabb in the dark here but what's your fuel pressure? does the rotary pump have an overfolw valve like a p-pumed motor? maybe a bad lift pump? maybe air in the lines...... smoke when it does it? or no smoke?

no smoke really when it does it just black smoke cuz I floor it to try to right it. I don't really know what the fp is reading as I don't have a gauge. but could you explain the overflow valve?

change fuel filter first. than try an apps adjustment and reset. NEED TO KNOW WHAT FUEL PRES IS! might have a injection pump going out. go to an autozone or kragen etc and have the codes pulled and get back to us.

sorry...this is my 91 can't really do the underhood throttle with a vp pump...besides I don't need one of those "overvalved" trucks.

I dont believe the lift pump would do that. The VE has the capability of drawing its own fuel, just makes it a dog. Possibly the governer spring, but I suppose Id be more inclined to believe the IP is on its way out. I'll ask some folks n see what I come up with for you.

what would cause the ip to go out though?

ttt

OK, I got with a friend of mine that knows much more then i do. It could be a clogged fuel filter, or bad lift pump. Does it start generaly easy? It could possibly be air in the lines as well. Just basically isnt getting fuel.

Try some of these, replace filter, install fuel pressure guage, put in a section of clear hose in the fuel line. (the closer to the IP the better) I dont know how to really test the lift pump, but I would assume you could pull the outlet, and use the manual prime lever and see if it is putting anything out. If that ends up being it, not a bad time to upgrade to a 2nd gen 12valve piston pump. :up:

The IP could go with age. How many miles r on it?

it starts great runs great when you ease it up to 50 anything over 1/4 throttle or 50 mph it cuts out. It's a bad lift pump I believe. Already changed fuel filter already bled the injectors.