Top sensor in this pic.
1993 3.0. On the water bypass outlet it's the far sensor on the drivers side. Blue. Circular. One wire. Broken. My truck won't start and throws a code 22. Is this why??

 

The great Karnak says: "you have 4wd, and an automatic."

Is he right?

The water bypass is surprisingly non-standard. I believe the blue one-wire sensor is to shut off the A/C; only on 4wd/auto.



So, no, it's not the cause of code 22. That's the sensor next to it (don't forget, the code just says there is an open/short in the CIRCUIT. The sensor could be okay. That's why you have a multimeter.)

 

Nicely done. Ok. My problem persists. So with the mechanical timing set properly, I can see with a timing gun that the ignition is 15-20 degrees retarded. The truck obviously won't run. What would be causing this?
I know the knock sensor will retard timing but it will still run. New sensor btw. Any suggestions?
Thanks!

 

Did you remove the distributor?

If it isn't re-installed correctly, so that it is off by one tooth, that's about 28° (18 retarded minus 28 = 10 BTDC). This is quite common.

 

I did have the distributor out as I just wrapped up a head gasket job. Thought I had it just right. I'll try again. Thanks.