Truck has sat for a couple years was running really rough when parked
things i have done so far changed fuel pump, dist cap, rotor, wires, plugs,
drained fuel cleaned injectors.

motor will try to start run up to about 500 550 rpm and then just die will not run more than a couple secs

 

If you hold your foot on the gas a bit, will it run?

 

it fires and runs up to about 500 rpms i have tried pumping pedal at that time but it wont stay running in short yes i guess it will hit but not run long

 

I would check fuel pressure and TPS to start.

Go to FAQ/DIY section and download service manual also.

Welcome to DF.

 

Clogged cat.

 

That would have been my next step after fuel and TPS along with this End-all Be-all plenum thread

 

places to start great thanks has had me lost for the past couple days on where to go next

 

Don't forget to get the service manual......

 

pull the pre cat o2 sensor to determine a clogged cat. once you remove the o2 sensor and try to start it, if it starts and stays running its the cat, and also a blown plenum, and possibly cracked heads.....

 

Had to stop work on this truck for bit but back at it.

i pulled the o2 sensor and it would idle it even reved up but wont stay running now it will start sometimes and idle but if i give it gas it will sputter and stall