Strange - 95 3.4 is flooding! (1 Viewer)

[caz]

All,

I developed a strange problem with my swapped 3.4 yesterday. It has been running like a top for 15k miles since I did the swap.

Yesterday I went out to start it, and it would not start. It turned over fine, and it sounded a few times like it may want to start, but did not.

It smelled like it was flooding!

After double checking a few things, I decided to unplug the fuel pump. I did this, and after a few seconds of cranking the truck started!

I plugged the fuel pump in again and the same thing happened. I had to unplug it again to get it to start.

Once I got it running with the fuel pump plugged in, I took it for a drive and it was fine.

I am at a loss on this one! Anyone have any ideas? Could it be a leaky injector or something?

Thanks,
CAZ

 

[LukeZero]

I don't know that engine specifically- but it could be a failed fuel pressure regulator. Lots of times the regulator is on the return line and only "bleeds" back to the fuel tank anything above a certain pressure to keep the injectors fed. If that regulator has failed in the closed position- you may be over feeding the injectors. The other possibility is a failed throttle position sensor (TPS). Maybe you're putting too much fuel in for the amount of air passing through the throttle body. Does this engine have a "cold start injector" that is only there to richen up the fuel load on cold start up? It might be stuck open.

By the way, this is a multiple choice test, pick the answer that best suits your situation.