MAF Guru's needed
 

Hey guys/gals. My MAF finally took a sh*t! When i was going through the test procedures Pro-Flow describes, a few things were slightly off key..

When testing pins C & D i got 9.2-11.3vDC(bad sensor) Ok now when i test pins C & D with the key on engine off i get like 5.8vDC

Is the 5.8vDC with the KOEO supposed to be there?

I am asking these questions, because the idiot at pro-flow, told me that there wasn't supposed to be 5+/- vDC through C/D with the KOEO. Yet LaMotta perf. here in orlando says it's a VREF wire(just like the TPS has) and is supposed to have anywhere from 4-5vDC. Any idea's?

After hearing what pro-flow had to say, I untapped the ENTIRE computer harness and found no burns/breaks. ...hmm...aggrevating...

thanx much guys!
.dave

I'll give you the long answer just to cover all of the bases.

Pin A -- VPWR, Vehicle Power (battery)
Pin B -- PWR GND, Vehicle Power Ground
Pin C -- MAF RTN, Signal Return
Pin D -- MAF SIG, Signal to EEC-IV module

*Note: Power to the MAF sensor is controlled by the EEC-IV module; Ground is through the PWR GND circuit to the battery negative (-) terminal.

At idle, the MAF signal voltage should be approximately 0.6V.

I'd first test for power and ground by disconnecting the plug and seeing if there's at least 10.5V between A and B.

Next, with the MAF connected and the engine running (all hoses connected), backprobe the MAF connector to battery ground. You should come up with between 0.2 and 1.5V. If not, I'd consider it junk. Mebbe good time for an upgrade anyway, huh? C&L's make more (proven) power anyway.

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Capri306, Moderator, The Mustang Works Online
1979 Mercury Capri, 5.0L -- C4 -- 2.73
1987 Mustang LX Notch

Capri, thanx for the reply, but i have covered those bases http://www.mustangworks.com/msgboard/biggrin.gif

With the car running i get like 9-11vDC(rediculously high). I have checked the entire harness for burns/shorts and there ins't any.

If anyone out there has some time, i would appreciate you hooking up a meter between pins C & D with the key on engine off and the air meter disconnected.

I get the same reading when i use my computer or a known good one from a friends car.

any help guys..?

.dave