Good TPS value. Good timing advance (should increase when accelerating). Vacuum reading is only an estimated value by the scanner, I think. We're starting to run out of options (that's a good thing).

The fuel trims will look odd for several drive cycles after the adaptive values have been reset. Remember Long and Short trims work together, so record both if you can, both at idle and at constant speed on the highway (accelerating and decelerating will change a lot).

 

Sounds good, ill do some more driving tomorrow and see what it looks like.
I was able to swap the camshaft position sensor today as well so we will see if that helps.

 

So after some spirited driving through the mountains here are some STFT/LTFT values with MAF #2
STFT1 Idle ranging from -1% to +5%
STFT2 Idle -1% to +5%
LTFT1 -14.06%
LTFT2 -14.06%

No miss codes yet, can still feel vibration in engine bay

 

And the miss codes came back
P0300 - Multiple misfire
P0302 - Cyl 2 misfire
P0340 - Camshaft position sensor (Thank you ebay parts)
P1316 - Multiple random miss

STFT1 -1 to +5%
STFT2 -1 to +5%
LTFT1 -20.31%
LTFT2 -20.31%

The fact that the misfire code moved from cyl5 to cyl2 has me thinking it might still be the camshaft sensor. The only appreciable thing I changed over the past couple days of testing was the camshaft sensor. This car has thrown cyl5 misfire for the past 40k miles of ownership and ive never seen a cyl2 misfire message. I kept the original lucas sensor that was in there after swapping in the cheap ebay part so I can always swap back and see if it moves to cyl5. Is this a typical camshaft position sensor failure condition?

 

OK. Good feedback. Can you monitor the short and long trim values while cruising at constant highway speed? Definitely need to verify a known good cam sensor.

I like ebay for lights and seat covers and such, but not for critical engine parts. I bought counterfeit ebay spark plugs once, that was enough.

 

Swapped in the old cam sensor and that solved the cam sensor code, probably fixed one of my oil leaks too because the o-ring was more of a plastic bevel at this point.

Crusing at 2250-2500 rpm @ 65-70mph
STFT1 -4 to +7%
STFT2: -4 to +7%
LTFT1: -21.09%
LTFT2: -21.09%
Occasionally when coasting downhill or near the top of a gear, torque will report 0.00 for STFT on both 1 and 2. Is this expected behavior?

 

So trims at idle and cruising are roughly the same. Over-fueling on both banks, but able to compensate with LTFTs. So no vacuum leak, but maybe fuel pressure is a bit high, which is not necessarily a bad thing.

Have you inspected the condition of the reluctor ring on the flywheel? Maybe one or two of the teeth are bent out of shape a little. That could cause the CKP sensor to trigger a miss at the same cylinder position. My '96 had a couple bent out of shape. I don't remember where to inspect. Under the transmission front cover plate, or through the CKP sensor hole?

 

I havent checked the reluctor ring. Ive never checked one on a disco but I understand the basic function of them in relation to the CKP. What is the best way to inspect tabs with the least amount of tearing apart engines? Im working outside in the snow on all this.

 

No need to tear stuff apart. I think it is accessible by the cover plate on the lower front of the transmission. Can also be viewed through the mounting hole for the CKP sensor with a mirror. The teeth should be equal distance on both sides of the sensor center pin. There might be a gap at TDC, I don't remember? There might be other access ports as well that should be fairly obvious (unless covered by grease).

 

Per rave theres two sets of teeth missing to indicate TDC
Just to verify, youre talking about the hill shaped piece labeled FRC2859 (pic attached). When I pull it will I need to re-do a seal? From looking at the rave it appears to be 9nm and im seeing a mention of a "gasket" and my searching leads me to a "594087" that I dont have on hand.