Alright. This is getting really tiring, and I don't know what else to look for.

I've had this '99 Disco I for about 2 months now, and have been chasing down a P1177 (- FMFR correction fault... running lean) since pulling it in the driveway. There have been other codes thrown, but for the moment, let's just say they were all caused by other issues that have since been fixed.

To date, these are the things I have done.

New post cat O2 sensors
New 8mm spark plug wires
New fuel temp sensor
New coolant temp sensor
New driver's side (USA) exhaust flange gasket (Yesterday)

After replacing the exhaust gasket, I took it for a good spin around the city. A good amount of stop & go traffic as well as highway driving. It ran really smooth and had a noticeable amount of increased power. Later that night, I went to pick up my wife from work....and the *&^% CHECK ENGINE light came back on, and it started to sputter. Didn't want to run very well after start up, either. Throw the OBD II reader on it.... P1177.

Now, would it be possible that the previous owner had some transmission work done to it, didn't tell me, and the shop installed the wiring harness backwards?

 

That is a hard one and so far I haven't seen anyone get past it.

 

If you could get to know a mechanic at the nearest dealership, they might have some insight. Only reason I say this is I got to know a Cadillac mechanic and when I can't figure something out I give him a call and he almost always knows the solution ...seen it before and can just rattle it off. We're talking about things that would be really hard for me to track down. I have just walked in the back door of dealerships before and started talking to mechanics before and most are receptive if you catch them when they aren't working on an extremely difficult project. The guys I've known were respectful to someone that took the time to learn how to do their own work. So, that's an alternative for additional info as you work through this problem.

 

The transmission on a DI is not electronic so any trans work should not matter.

 

Just took it here to the local Land Rover guru here in Albuquerque (Rob @ Southwest Rovers. 505.872.7818) He and his partner dropped everything they were doing and crawled all over my Disco for an hour straight.

Diagnosis:

1) Cracked weld on left side exhaust flange.

2) Fuel Pump getting enough electricity, not pumping enough fuel. Fuel pressure steady @ 22psi, should be 32psi. (Hence, the 1177 code all the time)

I'll be doing the fuel pump and filter this weekend. The weld will have to wait.

 

definitely keep us updated as this may be one of those rare but common problems that nobody really knows about, well I guess just something to check out when that code comes up!

I know my post didn't make alot of sense but we are talking about rovers here and when do there problems make sense?

 

Yes, wait...what?

 

No kidding, Chris. One of the first things I said to my wife when this started was, "This is acting like the fuel pump."

Well, on the plus side... I have a bunch of new parts under the hood!

I will update when I get the repair finished and run it for awhile.

 

I have found that on a DI if it "acts" like "X" it is usually "X" 90% of the time.

 

what I mean is there are alot of common problems with these trucks and then there are alot of common problems that only happen to a handful of us like the sunroofs are a common problem, most D1's will have a problem with the sunroof but the headlight switch only about a third of us will have a problem with it, therefore the headlight switch is a common problem but not as common as the sunroof (or the ABS, LOL)

and who knows maybe the fuel pumps not getting enough power is a common problem just not enough for most of our trucks to throw a code.