Put it all back together after a good cleaning *again*... hooked on with my vehicle explorer. The volt reading says 11000 for the maf at idle... I don't think it means 11K volts and am guessing it is 1.1V, but can't be certain. The maf check at that scorpio site said above 1 V and bad MAF, but I don't know that I can use their numbers to check MAF.

Also I'm seeing very different readings in the O2s after the cat. One hovers around .78 Volts or so and the other stays below .1 (Bank 2 IIRC) I'm thinking I need an O2, but which one, or do I need a CAT ...

What I could find of Bluegrass posts seems to make sense, but doesn't change what I've been looking for all along. Seems a vacuum leak, MAF, or too much fuel. I've got everything hooked back up again except for the PCV (darn rain and darkness cut me off) Wife will drive it tomorrow and see if cleaning the MAF helped at all.

 

MAF=Typical error value: <0.20V and >4.80V

I take it you have seen these then -

http://www.fordscorpio.co.uk/maftest.htm

http://www.fordscorpio.co.uk/cleanmaf.htm

The CCM page might be useful - specially for the 98. -

http://www.fordscorpio.co.uk/ccmonitor.htm

And this one - It's all about your problem -

http://autotechrepair.suite101.com/a...r_flow_sensors

Okay, I gotta go lol.

 

jbrew, you are the man.... when it comes to sources of info.

its a little early to tell but the last maf cleaning might have done the trick. Wife drove it all day and no CEL yet. I have to hook up to the PCM yet and check. will report back after I do.

 

Well? All better now? Finally

 

It's official, my truck has been cured. My LTFT isn't anywhere near 25 no matter how far the throttle is open. My wife drove it yesterday for about 50-60 miles, I drove it today for about the same and up a hill that surely would have set the CEL before, and even hauled a load of firewood home up a few hills on the way. No CEL, Not even a pending code. I might have a intermittent miss, but I can't tell. The OBDII reader shows an increase in High counter of Miss events (or something like that). I think I'll move on to the upper ball joints and exhaust now.

The cure was (I think) both the PCV elbow in the back of the intake and a fully cleaned MAF wire. I believe there is still a bit of corrosion on the wire but if I keep after it I think it will be fine. When I cleaned the MAF the first time a few months ago. I only sprayed in and let it come out the back of the maf. Well this apparently doesn't get all the dirt off the wires. You MUST pull it appart and spray both ways. I didn't at the time cause I don't have any of those stupid tamper resistant tools. So when I checked it out again a few days ago. I ground off the pin in the center of the screw heads so that I could pull it apart and clean better. I saw a bunch of dirt disappear off of the back of one of the posts, so I'm sure there was probably just as much on the wire. I took it a step further and got a Q-tip and alcohol and lightly swiped the wire and saw some specs of what I assume to be rust. Kind of shows in the pictures I posted. (those are after the full cleaning).

As a bonus the transmission seems to shift at more logical times that it was doing before, It would take a lot of throttle at times to get it to shift out of overdrive, much better now.

Thanks for stickin with me. Hope I can return the favor or at least pass it on to someone else someday. WoooHooo!!! I can finally move on with my life and put this project behind me.

 

- Oh yea, you have to take it apart to thoroughly clean. There's allot of conflicting info saying not to do this, you'll break a wire. Well, I haven't broke a wire yet, but I can see how it COULD happen. It's more of a common sense deal when cleaning.

I never use the CRC or MAF cleaner - They leave a residue if you just give it a shot. Q-Tips are a PITA lol, I've found that a thin straw that you usually get with a can of Gunk or WD40 - wrapped with a thin micro fiber cloth works best. Using Lacquer thinner to assist cleans her up the best. One of these products here along with Lacquer thinner are the best for the MAF IMO -



Alcohol was a good choice, but if you have a hardened coating on their , you'll need something a little stronger.

Oh yea, The MAF/TPS has everything to do with the trans. The PCM uses both sensors for the trans tables.

Man , it must have been running worse than you thought after fixing that lol. Perseverance paid off, pat yourself on the back for that.