I need some help finding the location of the MAF Sensor on my '91 Bronco. It has the 351 Fuel Injected motor.
I've looked all through the engine compartment and haven't a clue on what I'm looking for.
Can someone reply to this question??
Any comments are well appreciated.
How difficult is it to replace??

Thnx,
Mike

 

The MAF is after the air cleaner box, before the intake manifold. It's tubular in shape with a plug of wirezs attached to it.

 

Thnx, Blue'87 for your reply. Is the MAF attached to the "Throttle Body'? I've removed the throttle body, cleaned it, replaced the "Throttle Position Sensor", replaced the "Temperature Sensor", and replaced the "Idle Air Sensor". The only thing I see between the Air Cleaner Box and the Throttle Body\Intake, is the two air tubes. No other attachments.

 

Your Bronco does not have mass air, so there is no sensor for it. The Bronco never came with mass air until 95 or 96. Your truck has a system called speed density where it measures the volume of air not the mass.

 

Thnx Kameronth. I guess I've been chasin' my tail here. My Bronco has 393K miles on it and I've done a tune-up here a couple of week's ago, because it had some problem's running. I put in new plugs, plug wires, rotor, rotor cap. I removed the throttle body and gave it a good cleaning with SEAFOAM, and ran the liquid SEAFOAM through the main vacum hose from the brake-booster to the intake(before I put in the new plugs). When I crank it up it will idle @ about 1100-1200 rpm's till the temp come's up and then it start's a verry eratic acceleration\de-celeration through all the rpm range, from about 750 to 2000 rpm, then dies. When it dies I can hear the fuel pump still running, until I shut off the ignition. I put in a new fuel pump last Aug. so I don't think that's the problem. I did have the catalytic converter removed last Sept.
I wonder if that may be part of the problem?? Could the Oxygen sensor be sending the wrong message to the computert?? I did notice that when the thing is trying to idle, it start's pumping out black smoke, kinda like a stuck float in a carbuerator would do.
Any idea's?? Any help would be greatly appreciated.
I'm stumped.
Mike K.

 

It sounds like your throttle position sensor is needs replacing. It will cause an erratic idle. It's located on the bottom of the throttle body.

 

I had a problem something of the same nature. My 89 would idle down real low when I came to a stop after the engine was warmed up and would die. It would start right back up like nothing was wrong.

Then one day on a long trip the truck died while driving it on the freeway. This had never happened before and this time it would not restart.

Had it towed to a shop that could check it out for me but they could n't check until the next day. That night I tried to start the truck and she was running great again like nothing was wrong. Since I was out of town decide to still have a check down to see what they could find. They found nothing wrong!

Long story short I replaced everything you could replace. New BBK TB, every sensor on the motor. New fuel pump, filter, air filter, plugs & wires which were ford parts. I even bought a new computer with no luck. The truck how ever never did die while driving it. Only when I would come to a stop and only once in a great while. Which made it even harder to pin point. I tried to by-pass the EGR valve with no luck. Installed a new timing chain and gears. Like I said you name it I changed it.

After I changed the distributor the problem seemd to go away. I think I drove the truck almost 4 months with no more issues. It would show a small sign that it was going to act up but never did. I no longer own the truck.