Fuel Injection 'Looking Glass' Jim TenCate, Michael Hart
Fuelies: Ever wanted to check out your coolant temperature sensor? Simple, just measure its resistance with a Digital MultiMeter (DMM) and compare with the values in the ROM. Not. It's in an impossible-to-reach place and removing the connector (which unfortunately has a locking wire) and then getting the leads of a DMM in there is crazy. Better solution is shown here. It's been dubbed "Looking Glass" because it allows you to measure the various sensors of the fuel injection "looking" through the wiring harness (loom). You simply unplug the ECU, plug this box in, and measure whatever you're interested in. Along with learning your wiring harness is ok, you can measure
coolant (water) temperature
the throttle potentiometer (TR8) or switch (TR7)
the air flow meter (AFM) air temperature sensor
the microswitch inside the air flow meter
and the resistance of individual injectors too
Interested in renting it out? You pay shipping both ways (USPS flat rate box) and rental fee is just $10 (which is about what it would cost you to build your own version).