Flooding issue

[Fleetwood]

Hello Guys! I have a 350 TBI that injects way to much fuel to the point that the truck will not even start when I crank it. When I unplug the injectors, the truck runs fine until there is no fuel in the manifold. I read that this could be a coolant temp sensor. I replaced that and it did not help it. What could be causing this?

 

[gmbellew]

could be the injectors themselves are bad or leaking?

to start in clear flood mode, crank it with the gas pedal pushed down. that may help figure out if it is a cranking/starting issue vs a run issue.

 

[Fleetwood]

I don't think that it is the injectors. This first happened when I had a battery die in the truck. It randomly started working again after a few days with a new battery. Recently, I unplugged that battery and I am having this issue again. This makes me think it is an electrical issue. For clear flood mode, do I need to have the pedal down when I first turn on the ignition or just when I am cranking it?

 

[gmbellew]

pedal down, and then start cranking I believe.

 

[fast 99]

pedal down, and then start cranking I believe.

That's correct they were designed to work like carbs with stuck chokes. Try disconnecting the MAP sensor. Also, if the EGR valve is stuck open it causes the manifold pressure to drop then the ECM will add excess fuel.

 

[Fleetwood]

That's correct they were designed to work like carbs with stuck chokes. Try disconnecting the MAP sensor. Also, if the EGR valve is stuck open it causes the manifold pressure to drop then the ECM will add excess fuel.

Just disconnected the map sensor and it ran and idled with both injectors plugged in. It was super rich though. What is the next step? replace the sensor and vac line?

 

[fast 99]

You could try tossing parts at it, but data would be nice. Kind of sounds like you're on the right track. Remember after an engine has run extra rich, gas will pass by the rings. Either the oil needs to be changed or engine run for a time to burn it off.

 

[Fleetwood]

You could try tossing parts at it, but data would be nice. Kind of sounds like you're on the right track. Remember after an engine has run extra rich, gas will pass by the rings. Either the oil needs to be changed or engine run for a time to burn it off.

Ill go to a junkyard and get a ton of parts in a day or so. For now, I want to see if it could be the EGR valve stuck (I don't think it would be because it ran fine w/o MAP but hey). Should I be able to move the valve by sticking a screwdriver into where I have the picture and pushing it up and down?

 

[fast 99]

That will work but usually just reach inside with a finger and pull it up. If it doesn't change either the valve is open, or the passage is plugged.