It's been w while since ive had to come and ask, thanks to all the great info here, but fellas, I'm stumped.

Last week I had a guy do some basic maintenance on my 1995 Disco; re-gasketed the valve covers and oil pan to stop the leaks, plugs(NGK Platinum Plus ) and wires(NGK).

While he had the truck, he changed the oil. Went from Mobil 1 to Rotella 5-40 synth, changed the filter (Mobil 1) and cleaned the MAF with MAF cleaner.

he ran a qt of ATF before changing the oil. it was pretty gummy in there, even with regular oil changes. way worse than i would have expected, hence the change from Mobil 1 to Rotella. included a pic of the nastiness under the VC.

When i got back in, i noticed the Check Engine Light was on and it was running rough and now have a sticky lifter.

I also had him look at the water temp sensor, as i thought it was bad. He found it unplugged. That would have been my doing.

OBD gives a code 12, MAF. I cannot find anything more info than that on the subject. The fault doesn't clear.
Running rough, shaking the vehicle more than it should and the electric fan runs on start up.

he's a very competent mechanic, specializes in BMW and LR, stands behind all his work and has offered to let me bring it back. I know there is nothing intentional or incompetent, but something is not right, he's an hour away and i need the truck as my daily driver so im hesitant to take it back if i can fix.myself,

What am i missing? I dont want to change the MAF if that's not the problem. The plenum comes off to change the plugs. Could that be the culprit? i've checked the air flow connections from the air filter to the intake. all are good and tight. The air filter is not spotlessly clean but it's not overly dirty if i were driving a chevy 350.a little dusty is all,

Happy Trails to you all,

johnny

 

I know on my '95 that the wiring is getting brittle and I have had a few break, he likely had to un hook the maf wire connector to remove the maf, I would look at that connector first. then check the throttle body to make sure it's clean, the plenum needs a little sealant when it's been taken apart , and also check all the vacuum hoses to verify they are hooked up.......even a pro can miss or forget one. The fan switch ( on the intake manifold ) COULD be bad but maybe he pinched the wires putting everything back together..also the fan runs when the A/C switch is on.....you can clear the code by removing the 20amp fuse marked "injectors" in the fuse box under the hood for about 15-20 seconds with the ignition off

 

Thanks! great info to start running this to ground!

Cheers!

johnny

 

We'll, that didn't get it. Did all the checks, a suggested. All looks good. I went ahead and replaced the MAF this morning, as it's low hanging fruit. No luck.

The truck continued to give a code 12........ until........with no changes, minus some wd-40 stayed on the plenum to check for vacuum leaks, it started throwing code 44, O2 sensor. The 12 is gone, or still sitting behind the 44 which is not clearing. I'm not sure if it works that way.

Also discovered an exhaust leak at the manifold/pipe joint and very close to the O2 sensor. Can feel and hear the leak.

Any thoughts?

 

Is the replacement MAF an aftermarket unit from China? Those are known to be DOA right out of the box.

 

I assume it is. Came from 1A auto parts. But, why would that change the code from 12 to 44?

 

Use this procedure to clear faults:

1. Switch "on" the ignition.
2. Disconnect the serial link mating plug, wait five seconds, and reconnect.
3. Switch "off" the ignition, and wait several seconds.
4. Switch "on" the ignition. The display should now reset.

 

also..........on the 14CUX vehicles...........just pull out the 20amp "injector" fuse located under the hood for 15-20 seconds............and only one code will clear at a time

the o2 code may be due to your exhaust leak, these ECU's arent as sophisticated as the newer ones and the maf code may have been there 'cuz the ecu saw an air mixture fault and picked the maf sensor to blame it on first...perhaps the o2 hadnt shown a problem long enough to register yet at that time, or the maf (being screwy) messed up the fuel/air mix and the o2 couldnt cope with it

one thing at a time though....you know you need to fix the exhaust leak, so start with that......and yes the chinese mafs have a virus...lol.....if you end up needing another one try Will Tillery or Paul Grant for an oem used one , Lucky8 has a decent aftermarket one new

 

I've been doing this, it's just that the faults don't clear. At first it was 12, then today it switched to 44. The exhaust leak and the codes started at the same.time.

 

Ok. I looked for the 20A breaker, but none of them looked like injectors. I'll pull up the rave and give it a read. I'll have the leak fixed next week. And.if.the.new MAF is bad, I still have the original one. Thanks for your advise!

Me and.my mechanic had a real good laugh at Rois Landver drivers expense!