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Discussion Starter #1 (Edited)
If you suspect your MLPS may be bad, here is some good info for testing.

Specs - MLPS Voltages and Resistances (Gear, Volt, Ohms):
Park, 3.97-4.85v, 3770-4607 ohms
Reverse, 3.25-3.96v, 1304-1593 ohms
Neutral, 2.55-3.11v, 660-807 ohms
Overdrive, 1.88-2.30v, 361-442 ohms
Second, 1.23-1.51v, 190-232 ohms
First, 0.61-0.75v, 78-95 ohms

For the backup lamps, the switch must make continuity between pins 2 (Pink/Orange wire) and pins 3 (Black/Pink wire).

For instance, my car was the following (which is a working MLPS):
P - 4.410v
R - 3.615v
N - 2.860v
D - 2.105v
2 - 1.390v
1 - 0.675v

Might be good sticky info...
 

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Discussion Starter #3
Other Numbers

It's good info for static bench testing, but often times the corrosion that ruins them inside makes the problems intermittent, hence why most people experience random behavior.
Those numbers of my car are not static, I took a bunch of measurements right off the ECM while data-logging today (dynamic baby! lol), but I totally understand by what you mean by intermittent problems and bad connections - I fix them every single day! Usually, by the time someone brings a vehicle to our shop, they've tried to fix it, their son/brother/uncle/shade-tree mechanic/know-it-all friend has already tried and more often than not, made problems worse!

I did wiggle the gear shifter in each of the positions (to jiggle the mlps connection) to see if the numbers would change. At the MOST, I could get them to change by 0.01 volts.

If you're interested in any of the other measurements, here they are:
TPS @ idle: 0.975v
TPS @ WOT: 4.630v
MAF @ idle: 0.84-0.870 @ idle (I thought that might be a bit high)
MAF @ WOT: didn't get good measurements cause as RPM changes, youknowwhatimean?
Fuel Pulse @ idle in Park: 2.5-2.9ms
Fuel Pulse @ idle in Drive: 3.2-3.4ms
IAC @ idle in Park: 17-19%
IAC @ idle in Drive: 12-13%
Engine Load @ idle in Park no a/c: 13%
Engine Load @ idle in Park with a/c: 17%
Engine Load @ idle in Drive no a/c: 18%
Engine Load @ idle in Drive with a/c: 21%
O2 Sensor 1 Upstream @ idle: .07-.83v
O2 Sensor 2 Upstream @ idle: .07-.85v
O2 Sensor 1 Downstream @ idle: .29-.77v
O2 Sensor 2 Downstream @ idle: .69-.79v
Idle Speed in Park: 725 rpm
Idle Speed in Drive: 590 rpm (little low)
Barometric Pressure: 13.95psi / 28.40 inHg
Ignition Advance @ idle: 22* BTDC
Completed Driving Cycles: 54

There was a lot more, but that's all I wrote down (I used an SPX Genesis scanner/data-logger). I wish I had taken the Engine Load numbers before my pulley swap, that's would have been an interesting comparison.
 

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Discussion Starter #4
Information

You are all welcome for this information. I know most people don't have access to it and I was just trying to help people out. You kind of ticked me off, Chris, with your criticism and "but's" and "static bench testing". I was just trying to help, I've seen a lot of threads where ppl don't know how to test these different sensors, don't know about potentiometers, 5 volt references, circuits, whatever, and don't know where to begin. I'm trying to help people and give them a starting point, isn't that what a forum is supposed to be about? You're not the only one with some good info here, Chris, and the deity of MN12's. Some of us us low-lifes have helpful information to contribute, too. I respect you your knowledge, Chris, that's why I've gone to you about other topics and issues, you just said the wrong thing in this instance.

Anyways, rant over..... :zsoapbox:

Sorry everyone, have a great week-end! If all you admins and mods want me to delete all my posts here, I'll do it in a heartbeat.
 

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Wow Richard, take a step back and relax. I apologize if I came off as condescending or otherwise unappreciative of the info you posted. It's good that you get that info out there because it might help someone along the way. The point I was trying to make is that it's extremely hard to test something like the MLPS by just measuring the resistance and/or voltage. You had access to a scanner to give real-time diagnostic data, but how many people of the general populous here will? Not many. So if someone takes off their MLPS and bench tests it (that is what I meant by static), they will probably see it pass by falling in the correct ranges. But the MLPS is subject to many things, a few of which are vibrations from the engine, vibrations delivered through the chassis from the road, heat from the exhaust, and varying levels of humidity from the outside air. All of these things and others are extremely dynamic while driving, and these truly can't be simulated unless the MLPS is actually on the car. But again it comes down to who is really going to have access to the type of scanner that will give them this info. Again, thanks for posting the info and sorry if I offended you. There truly wasn't any criticism in there. Can't we all just get along?
 

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Discussion Starter #6
Wow Richard, take a step back and relax. I apologize if I came off as condescending or otherwise unappreciative of the info you posted. It's good that you get that info out there because it might help someone along the way. The point I was trying to make is that it's extremely hard to test something like the MLPS by just measuring the resistance and/or voltage. You had access to a scanner to give real-time diagnostic data, but how many people of the general populous here will? Not many. So if someone takes off their MLPS and bench tests it (that is what I meant by static), they will probably see it pass by falling in the correct ranges. But the MLPS is subject to many things, a few of which are vibrations from the engine, vibrations delivered through the chassis from the road, heat from the exhaust, and varying levels of humidity from the outside air. All of these things and others are extremely dynamic while driving, and these truly can't be simulated unless the MLPS is actually on the car. But again it comes down to who is really going to have access to the type of scanner that will give them this info. Again, thanks for posting the info and sorry if I offended you. There truly wasn't any criticism in there. Can't we all just get along?
Apology accepted. I also apologize for getting short with you. I just felt I'm trying to encourage people to do their own troubleshooting while you were trying to discourage them. It's over. As for the having a $2000 scanner, you don't need one. Most of my life, I didn't have access to one and I managed. Testing an MLPS, I wouldn't pull it out and bench test it, either. If I had to do it in my driveway, I'd use my $10 multimeter! Just turn the ignition on, crawl under and probe the correct wire and write down the voltages found in each gear. Then I'd compare them to the chart I listed above. Simple biscuit. People over-complicate stuff and I have no patience for it.

I love beating Alldata at it's time estimate for it's big jobs. Case in point:
Alldata says changing the lower control arm bushings in a Mitsubishi Pickup would be 2.5 hours PER SIDE. I had them both done in 20 minutes. I just jacked up the outside of the control arm (where the wheel mounts), and put a second jack under the inside of the control arm (where it mounts to the frame. I then removed the ONE BOLT that goes through both bushings and the control arm. Then I let the inside jack down. The spring pushes the control arm down and you can just pull the bushings out with your hand and put the new ones in. Raise the jack until the holes line back up, put the bolt back in. DONE! Go to other side, repeat. How freakin' easy is that? According to alldata, you remove wheel, remove spring, blah blah blah. Screw all that - why bother?

Like I just PM'd you about swapping a 96-97 Bird computer into a 94-95 Bird. You read the threads here about the people who have done it, and it's a nightmare! Replace harnesses, splice dash harnesses, replace sensor plugs - are you kidding me? Relocate 4 pins on ECM, cut 2 wires, run 7 new wires out to engine compartment from ECM, remove ignition control module. THAT'S IT! I don't see all this over-complicating information out there about this procedure. If and when I do this, I'm going to tell you all EXACTLY how long it takes me.
 

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1994 Cougar XR7 DOHC/5-Speed
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Overcomplicating? I made a jumper harness for the dash to PCM harness so I could simply plug and play the 96 harnesses. I could have modified the 94 harnesses but that defeats the purpose since the only real benefit is the revised layout.

FWIW, it took me about 2 hours to make the dash jumper, the O2 jumper, and modify the trans tunnel harness. Swapping in the 3 other harness took maybe a half hour(though having the trans out made installing its harness alot quicker )
 

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Discussion Starter #8
Overcomplicating? I made a jumper harness for the dash to PCM harness so I could simply plug and play the 96 harnesses. I could have modified the 94 harnesses but that defeats the purpose since the only real benefit is the revised layout.

FWIW, it took me about 2 hours to make the dash jumper, the O2 jumper, and modify the trans tunnel harness. Swapping in the 3 other harness took maybe a half hour(though having the trans out made installing its harness alot quicker )
You swapped in 3 complete harnesses in 30 minutes? That's completely removing your existing hooked up, attached harness, then reattaching (I'm assuming you started with an already removed 96-97 replacement harness) the new harness and reconnecting all sensors. That's pretty good! That just sounds like a LOT more work than modifying the existing harness. Aren't those run under carpets/dash, attached with those little plastic clips everywhere, wrapped in that plastic wire wrap and taped all over the place. Then you have to make sure you attach the new harness everywhere because any place that the harness may move/rub is eventually gonna go through the insulation and cause a problem. If I had to because I was told to at work, I would. But for my own car, re-pinning and running a few wires (as opposed to running EVERY SINGLE wire in the harness) sounds much easier. To each their own; your ride looks very nice and you did a VERY nice job with it. Kudos!

EDIT: As an afterthought, from the looks of your ride, you completely went over everything, right? So it wasn't like it was so much more work to just change the harnesses since you have had everything tore apart for rebuilding anyways, right?
 

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1994 Cougar XR7 DOHC/5-Speed
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True, If I solely was swapping the harnesses it probably would have taken longer, I grouped it into the trans swap so I could use the 96+ TCC solenoid right away. Nothing other than the trans, wiper cowl, console and passenger kick panel were removed. I have completely gone through my car but not all at once lol

Honestly swapping the harnesses alone was a breeze, the hardest part was pushing the PCM connector through the firewall, otherwise the harnesses basically go in and out when everything's disconnected.

Trust me, I've gone overkill before (including my latest wiring project), this was nearly plug and play other than making the jumpers.
 

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I just ordered a new mlps, and it came with a rewire kit; Did I order the wrong one, or will all of them need this in the future?
 

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I just ordered a new mlps, and it came with a rewire kit; Did I order the wrong one, or will all of them need this in the future?
Last couple I've gotten had the new style Connector Kit with it - Even if you already have the new Connector on your harness it's nice if you've broken a Clip or something on existing one - Of course you only use the Pins you need but new Connector had like 10 Pins for the AWD cars, trucks etc...
 
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