My '99 Disco I has gone through a few repairs since we've had it, I'll list those below. But, it's still throwing the P1177 (Maximum Negative FMFR Correction Fault) when it's been running awhile. When you try to start it hot, it sputters and wants to die unless you flutter the gas for about a minute. Then it "catches" and runs fine.

Also, thanks to everyone who has helped me try to find the problem. You guys are a HUGE help!

Repairs:

New post cat O2 sensor
New spark plug wires
New coolant temp sensor
New fuel temp sensor

I'm thinking about listening to all of the fuel injectors next to see if there's one sticking.

I do have one question. On the passenger side (USA) of the engine, on the fuel rail, there is a covered & threaded port. Is that for a pressure gauge?

 

Yes it is a pressure gauge port there should even be a little sticker there that says what it is for.

Edit: Now that I think of it the pressure port I am thinking of is not on the fuel rail but sticking out from the fuel line on the drivers side. It has a green cap as I recall and has a sticker on it that says it's a diagnostic pressure port. Not sure if that is what you are talking about.

 

my first step would be to pull the plugs out and see which one looks like its been in a coal mine for most of its life. i think youre on the right track with the injector, but id say more likely not fully closing... and yes, the port is for fuel pressure tests

 

Plugs are all good, look normal.

After I cleared out the P1177 code there have not been any issues and the Check Engine light has stayed off. Let's hope this is the trick!

Thanks again for the help. I would have been entirely lost about what to do and look for if it wasn't for this site.