My b3000 sputtered and die yesterday, cost me a tow. I changed the fuel filter and still nothing, so I pulled the gas tank and replaced the fuel pump. Progress, the truck starts and runs but idling at 3000 rpm's. No adjustment was done to the idle set screw and the truck idled fine before. does anyone have experience with situation before? I don't know where to look next.....help

1994 b3000

thanks\

 

Did you ever get an answer or figure out what the problem was?

 

no still stuck.........

 

Is it safe to assume that you have gone back and checked all the vacuum hoses?
Does the truck have A/C? Sometimes there is an idle increasesolenoid that allows more air directly in @ the intake manifold or carb base to bringup the idle when the eng is under load from the A/C compressor. Could thathave been activated (if it has one?)
I would think it has got to besomething pretty simple?

 

I'll take a look at that.thanks

I was look over the truck today I thought it might be a pressure problem with the fuel line so released pressure at the fuel rail a couple of times, thinking maybe air was traped in the line. I also found out that the engine will stall if I disconnect the breather hose from the clean air box. This doesn't make any sense to me why it would stall after get unrestricted air flow.....

 

When you disconnected teh breather line from the air box it allowed the engine to suck in air that wasn't being measured by the airflow sensor which would cause a really lean condition... Although normally by doing this it willjust idle very rough...This makes me think you may have a vac leak somewhere past the throttle body..... The next though would be by some chance that maybe your idle air valve took a crap the same time your fuel pump did....

 

I've checked for vac leaks and can't locate any. I did change the air idle control motor(iac) and the idle came back down to normal, but it only lasted untill the next time I started the engine and then back to 3000rpm's. I think it might be my mass air flow sensor(big$)hope it not. I have to read the computer to find out whats happening. I miss the caburator days...before computers.