'99 SD 4.0l V8

I'm getting p1179 and P1177.

P1177 - Maximum Negative FMFR Correction Fault

P1179 - Maximum Negative AMFR Correction Fault

Ok.... I'm not a genius, but that is pointing to rich fuel levels, right? If I knew what AMFR and FMFR were, I might be able to narrow it down a bit.

So... Since this engine has a coil pack and no old school distributor, how does one deal with this. Or-- Where the heck is the air flow valve?

 

Those are hard ones to track down, I have always suggested checking for vacuum leaks based on what I have been told in the past, which I could tell you more.

 

Thanks, Mike... I'll look the vac lines over.

It just threw a new one at me P1316 - Misfire Excessive Emissions Fault. It does seem at times like it's running on 7 cylinders, but it will mellow back out. The previous owner said that he just got new plugs....I guess I'll crank those out and take a peek. I don't have a manual...does anyone know what the gap should be?

These things have coil packs, right? (sigh) What happened to the good old dizzy?

 

First, what plug and ignition wire set is on the truck, are the wires gray?
If the plus look old, have a gray ring around the base of the porcelen, then you need new ones anyway.
As for the coil pack, yes, since 96 they have had coil packs, which are far better then our old distributors.

 

The previous owner just put Bosch platinum + plugs, and the wires are black.

 

Ok.... So today I'm going out and pulling all of the plugs to inspect for anything suspicious.

Is there a proper brand/type of plug wire that is required other than the normal silicone "high temp"?

 

I think just about everyone here recommends the Magnecor 8mm wire set.

Eric

 

Well, I found all the plugs were gapped @ .032 and I regapped them to .035. I took the thing around the block (which has about 100' of climb) and it pulled really strong and steady, even with the a/c on.

I also found that the air intake tube (right at the throttle body) was really loose. Air was definitely getting in. So I tightened that up as well.

Before the run around the block, I cleared out the OBD codes (P-1177 and P-1179 respectively). The CE light didn't come back on, and I ran it pretty hard.

Let's hope this is the trick. I really need to get this little piggy smogged and tagged.

 

btw; how many miles on your Disco?

 

About 131,000

...and it flooded out on me yesterday. Something's definitely amiss, and I can't seem to track it down.