Hello again,

85 3VZE has ran GREAT for two days now. This morning, back to running rough and check engine light on. Code 24 & 25.

Have been researching previous threads and will test the ECT wiring. Here is what I noticed though...

1. Forgot to put the clamp back on to the heater hose that goes into the middle of the firewall. Coolant level was a little over 1/2 gallon low.

2. I noticed the temp gauge had come up to the middle within a couple of minutes of starting. I would have thought It might take about 5 minutes of driving before the gauge would read in the middle. Engine is NOT overheating.

Might the lower coolant level affect the ECT causing the ECU to act up?

I have cleared the codes to see if they come back again.

Respectfully,

DJ

 

It might an issue if coolant was low enough to overheat, but only because the ECT sensor responds to coolant temps, anyway. Of course, a bad connection/sensor would cause problems, but 24 is your air intake signal, DJ. Start looking at your air flow meter and/or connections. The easiest to do first is pull the boot back on the connector and make sure all the wires are in the clip snugly. Inspect the wiring throughout the length of the cables by using an ohm meter to read resistance at the ECM end. Or, you can test the voltage at the VAF meter end of the cable with the key on. It's major easy....unless, you don't have a meter. That might pose a problem.

 

Hey,

I appreciate the heads up. I think ole Murphy is slamming me with his law book. My job is working with traffic signals and components and I like to tinker with electronics. Went out to take measurements on the IATS, grabbed my Fluke 78 DMM, switched to ohm's scale to test the meter leads and got 28 ohms resistance. Not good. Replaced the 9 volt battery same result. Got to looking at the SMD's on the PCB and noticed there was some corosion on the PCB. ARRGGGGHHHH!! Will borrow a meter from work tomorrow and test the values and check the connections.

Many thanks,

Jeff