98 5.0 MAF diagnostics
Probing the connector, I have battery voltage on Red and black ground is good.
Key on, Connector disconnected from MAF
Red Wire (Power) is at 14.2V to chassis and battery negative
Black Wire (Ground) 0.05V to chassis&battery, 0 Ohms to Chassis & battery negative.
T/LB: 0V, 8.4MOhm to ground
LB/R: 0V, 0 Ohm to ground
Resistance between T/LB and LB/R: 700 Ohm
Key on, connector connected to MAF:
T/LB: 0V, 0 Ohm to ground
LB/R: 0V, 0 Ohm to ground
Resistance between T/LB and LB/R: 0 Ohm
Engine Running, voltage T/LB to LB/R
Idle (700 RPM) 160mV
Rev Up (?? RPM): increases with speed up to about 225mV
Diagnostic reads .24 lb/min for MAF and 0 for MAF voltage
Connected up the AutoTap,
While running, disconnected MAF connector and feed power into connector signal leads via AA batteries.
1.5 V (1XAA) feed, OBD-II reported MAF V=1.2, MAF Rate - small change (~0.3lb.min)
3V (2XAA) feed, OBD-II reported MAF V = 2, MAF Rate: 3.3 lb/min
I know the MAF is a resistive device, so not sure what the readings should be with and without the connect + the ECM is in the mix too. Can someone help me figure out if this is the MAF, wiring, connector, ???. I'm leaning toward connector or wiring right now.
BTW: When problem first started I thought it was the MAF sensor and replaced it. That did not fix things which led me to digging deeper.


