Ford Help Again. MAF sensor?

[katoranger]

Been working on a 93 Explorer with about 300K on it. Surprisingly it still runs. Idles rough and sucks alot of gas. About 11mpg highway.

Fuel pressure checks out at about 35psi and it holds pressure after shut down. I thought it was the FPR.

I cleaned the MAF with electronics cleaner, but with it running at idle there was no change with it plugged in or disconected. This is leading me to think it is completely bad. Reading on other areas also suggested that a relay for the MAF may be bad and no power is getting to it.

I haven't check to see if power is getting to it. It belongs to a friend who keeps adding duct tape.

[AZ200cc]

They're delicate, And cleaning them can actually damage them. Might try to find a used one could save some bucks.

[katoranger]

I got the owner on a junkyard mission today. It may be that we damaged it. I followed all the instructions I could find online. Maybe I didn't wait long enough for the contact cleaner to evaporate.

The thing is that is actually ran better after cleaning it. Maybe I did destroy it and now it is running in limp mode. Can't make it worse.

[PoManzATV]

keep in mind that MAF sensor won't even come into play until the engine reaches normal operating temp and the ECU goes into closed loop mode, reading off all it's sensors to make fuel trim changes. When the engine is cold and in open loop, you should be able to disconnect the MAF w/ no ill effects. A bad coolant temp sensor could be holding the ECU in open mode giving the horrible MPG? Just an idea!?!

Joel

[katoranger]

Thanks, It may not have been up to temp. I will put ECT on the list to check. The temp guage works, but I don't know if the same one triggers the PCM.

He is getting some "spare parts" from the junkyard today. Doesn't hurt to have extras.

I will have to check the MAF after it is up to temp.

Allen

[Reveeen]

Originally Posted by PoManzATV

A bad coolant temp sensor could be holding the ECU in open mode giving the horrible MPG? Just an idea!?!
Joel

Even a thermostat, that is not bringing the engine up to temperature, will keep the system in open mode. This seems especially true on Fords.

A side note: I just rented a 2010 Nissan Maxima for a small tour and it got worse mileage than my Ranger.

[FastDoc]

Have you checked the technical articles at www.therangerstation.com yet? Good forum.

[davidsonsgccc]

I DONT KNOW IF THIS WILL HELP BUT I HAVE A 94 4LITER FORD RANGER AND THE MAF IS BAD . IT WOULD IDLE GOOD BUT WHEN I ACCELERATED IT WOULD STUMBLE AT FULL THROTTLE. I DISCONNECTED THE MAF AND IT WOULDNT IDLE GOOD BUT RAN GREAT WHEN I ACCELERATED. IT RUNS A LITTLE RICH I BELIEVE WHEN IT IS UNPLUGGED. I ADJUSTED THE IDLE AND HAVE BEEN DRIVING THAT WAY SINCE. IM CHEAP

SHAWN

[katoranger]

Originally Posted by FastDoc

Have you checked the technical articles at www.therangerstation.com yet? Good forum.

I have been there, but need to check through more of the tech help. Right now we are just trying to coax a few more months from the thing.

It runs and gets up to temp so I don't think we have a temp problem. It could be though.



davidson, I thought about leaving it unplugged too. We don't have emissions in my county. I am sure it has been driven this way for along time already and I am afraid that it is more than one thing causing the problem. With the rich condition likely the O2 sensor and cat are gone too.

Allen

[phil]

i know this is may be against your religion but you may save yourself a lot of guessing by having someone with a scanner run whats called a key on engine running test (koer) ford is really good for showing everything wrong when this is done, if you want stop by ill do it for free

[AZ200cc]

Yah the cascade effect sucks on newer cars, One sensor can make everything go out of whack. Gone are they days when people could swap out a theromstat for a colder or hotter one. All it does is cause trouble.

[TurboT]

..or you could do away with it and drive a DODGE. Fix all your problems.

....sorry I can't be more helpful. If you needed rod or crank pin sizes I'd be your man, but when it comes to sensors and stuff, I'm out.

..good luck with it.

[katoranger]

Originally Posted by phil

i know this is may be against your religion but you may save yourself a lot of guessing by having someone with a scanner run whats called a key on engine running test (koer) ford is really good for showing everything wrong when this is done, if you want stop by ill do it for free

Is was ready about this. Will need to check it out and see what it gives me.



TurboT. Still waiting for my Dodge. CTD someday.

This ford should have been tradin in last fall as a clunker.
Allen

[montanaoffroader]

Last summer a friend of mine had similar problems with a 92 Exploder, turned out to be a bad intake gasket. Took us a little while to figure it out, it threw out a bunch of codes in KOER test.

With 300k on the clock, I think I would check the compression before I spent any real money on it, though.

Just my $.02

Good Luck, Mike

[AZ200cc]

Originally Posted by TurboT

..or you could do away with it and drive a DODGE. Fix all your problems.

....sorry I can't be more helpful. If you needed rod or crank pin sizes I'd be your man, but when it comes to sensors and stuff, I'm out.

..good luck with it.

Thats funny, I sell more parts for new dodges than any other car on the road. The vehicle I sell the least parts for are Subarus and Hondas....Fords are the hardest to figure out because they change a part every six months and chevys can't make a fuel pump or a cv shaft last to save a life. My best advice is to purchase an older vehicle with simple problems or buy A subaru or Honda. I might also go with only a newer chevy..They are fighting hard to get back in the quality fight.