3.9 V8i Floods when cold.

[pfb]

My '95 3.9 V8i runs great, makes good power, and starts effortlessly 999 times out of 1,000.

Once in a while, on a cold day, it doesn't start right up, seems to flood, and then is an absolute bastard to get running. Foot off the gas the entire time, but once it floods, it won't clear no matter what I do with the gas pedal.

By intentionally tripping the underhood accident fuel cutoff, I am usually able to clear out the flooding, then by hitting the button to reset the fuel at the perfect time when it's trying to fire, I can usually get it running again. Obviously, this is a two person job.

This AM, it happened again. I ripped out the fuel cutoff switch and wired in some extension wires and a switch so I could turn on and off the fuel from inside the cab, and was able to get it started.

Question: What is the root cause of this problem?

Why does the engine flood on occasion and what can I do to fix it? A sensor? maybe 02 sensor? Did I read somewhere about a PROM update for the 3.9 V8i ECU? Is this self-installable? Who sells the proms?

Battery, battery wires, and ignition wires are all in good shape. Thanks in advance for any advice.

 

[pikasso5]

I'm getting the exact same thing. I'll post anything if I find out.

 

[joey]

Sounds to me like you may have a sticking fuel injector.... I would start by running some good injector cleaner though your system, or just pull them out have clean them on the shelf... or just replace them.