Need help with MAF code 157

[opelgtman]

I have been trying to clear this code for weeks now. I have a '93 Explorer Eddie Bauer and it has been running rich and throwing this code 157. So far here is what I have replaced:

MAF
IAC
ECT
TPS
Cat
Plugs and wires
Seafoamed the engine

It runs sluggish and seems to miss still. The running rich is not as bad as it was before I started replacing parts.

How do I test the voltage levels going to my MAF? What should they be? Do you think it could be my connection to it? The check engine light will come on within 2 minutes of starting my explorer.

 

[B2scott]

Maf

MAF systems typically use a 0 to5 volt sytem. So if you have a volt meter you can check the voltages to and from the pcm. There should be 3 wires on the MAF sensor, one is a 5 volt referance from the pcm, one is the metered voltage that the MAF sends to the pcm, and one will be a ground wire. So to test these you need the engine running and check the wires one at a time by hooking up one end of the voltmeter to a good ground and use the other end to probe wires in the back of th MAF connector, one should have 5 volts, one should have around 1 volt or a little more,and the last one should have no voltage. If the 5 volt wire has less than 5 volts you need to inspect the connector which is a common cause. Hope this helps and feel free to ask questions

 

[opelgtman]

How do I replace the connector? Do I just get one from the junkyard and splice it in? Or does it have a connection somewhere farther down in the engine bay?

 

[B2scott]

connector

Ford should have the conector and the wire terminals needed to put the new connector on. Was there sign of damage at the connector or did you test it?. cause just replacing the connector might not fix the problem unles you know it is bad. You could splice in one from the junk yard to see if it fixes the problem, but not really the right way to do it. it should be tested for voltages to make sure there is not a problem in the rest of the wiring. good luck

 

[opelgtman]

I got a multimeter today

Using the battery post as ground, I tested the maf connector. Starting at the left with the open end of the connector facing me....

Red cable - 14.6
Black - .135
Biege with blue stripe - 1.87
Blue with red stripe - .4

So what should I do now?

 

[opelgtman]

I went to a pick and pull today and got another pcm. Swapped it out in the parking lot and the explorer runs amazing now.

Now just to figure out the ABS light lol.

 

[Blacksheep Josh]

I went to a pick and pull today and got another pcm. Swapped it out in the parking lot and the explorer runs amazing now.

Now just to figure out the ABS light lol.

look around the braek booster area under the hood. my buddy had a 95 f-150, and his ABS light was on, and we were looking at it one day and i noticed a plug that was unplugged, i plugged it in and it fixed it! it was actually quite funny...

josh: "hey, this is unplugged... looks like it goes there" plugs it in.
sean: "i swear, if that fixes the abs light, i'm killing you, i've spent weeks working on it." checks dash, lets loose flurry of curses.

just check to make sure everything is plugged in, also check the fuses. could be something simple.

 

[B2scott]

Thats awesome Opel sorry I havnt been gettn back to you been busy, but the pcm was a likely culprit for the problem and its great you got it fixed not sure about the abs light though.

 

[33exploder]

Scott, I had an abs light about 7 years ago. I when to the local stealership to hear the most expensive repair, short of new truck. To fix it.

R & R the abs pump, master cylinder, 3 wheel speed sensor,2 front calipers, 2 rear wheel cylinders flush and bleed system. [Over 2 grand].

naturally I assumed the shop manager had bumped his head. I paid for their time thanked him and drove home. Jack up the truck to ohms test the wheel speed sensors, as soon as the tires cleared the ground I hear it clunk on it's spindle, now I have something else to check. All sensors check out good. While I had it on jacks I pulled an inspection on the wheels and found worn bearings, R & r all the front bearing and seals reinstalled the rotors torqued to 18 ft lbs. Set it on ground and road test. ABS light never came again.
Apparently the sensor and the shutter wheel on the rotor have a prescribed gap allowance, a worn wheel bearing will cause an excessive gap which causes the ABS light to illuminate.
have fun.