frayed reference sensor?

[uvachief]

Well I may have found the culprit of my starting problem. My bottom cross reference or speed sensor is frayed. I pulled the ecu dme box and the oms and voltage all checked out. See below. How do you disconnect the male plug?

[mytrplseven]

Good find. On the other side of the bracket is the female side of the connector. There's a thin wire that wraps around the fat portion of the connector. Take a fine screwdriver or thin, pointed knife tip and lift the wire off the connector on the sides. Don't lose the wire. Once it's lifted, the plug should easily pull out. Before you plug in the NEW sensor, put the wire clip back into it's recesses on the sides of the connector. Then when you plug in the new sensor plug, it'll click right in and you're done.

[uvachief]

When I went to disconnect the male from the female, it just came apart. No wire and the male connector was cracked or broken around the fringe. I saw no gold wire. It just came apart without any effort.

[uvachief]

Could any animal have gnawed the wire?

[tamathumper]

After many years of heat cycling and engine-related chemicals, it was just time to fail. That heater control valve in the background might be on its last legs too. This stuff just gets crispy.

[uvachief]

Yeah but I just replaced the reference sensors 4 years ago and the heater control valve 2 years ago.

[tamathumper]

Really should have been good still if they're that new. There's no sign of animal gnawing in the picture, it's just a clean break that would leave no gaps if you pressed the two halves back together. Animals and insects remove material.

Does the cable get bent or yanked on a regular basis, or does anything hit it when the engine moves?

[uvachief]

I tried black taping it together as best I could but I still cannot get it to catch when trying to start. She cranks but won't catch. Since I cannot get the engine to run, I cannot see if anything is hitting. Looks clear or would have been cut up worse.

[mytrplseven]

Since the wire separated, I assume from pulling, you can't be assured that the conductor inside is intact unless you take an ohm meter and see if you get around 1000 ohms between connectors as shown:
Sensor Resistance Checks


Disconnect the Sensor plug connector at the back of the engine compartment.
Using a multi-meter, check the sensor resistances as follows:

Speed Sensor
Terminals Resistance Reading
8 - 27 600 - 1600 ohms
8 - 23 > 1 M-ohm
Reference Sensor
Terminals Resistance Reading
25 - 26 600 - 1600 ohms
25 - 78 > 1 M-ohm

[uvachief]

I'll test it. Already tested the dme ecu plug. Anyone got step by step instructions for removing the old sensor? Do you just loan the nut and it comes out?

[uvachief]

Oh yeah. .. don't drop the reference sensor bolt onto the bell housing!

[Dean924s]

It is from the movement of the motor causing repeeted flaxing of the wires.

Mine were much worse.

I cut the wires off the plugs and then took a dermal tool with s grinding stone attachment and carefully ground done the plastic of the plug to expose the connectors in the cast plastic. There should still be parts of the wire insulation attached to match up the colors. Strip back the wires on the lead form the sensor and put shrink wrap over the whole thing and then over each individual wire and then re soldered things back together and put the shrink wrap over and then wrapped in electrical tape. Works good as new and no more intermittent no start any more.

I tried to remove the sensors af first but they are stuck in there so I did the next best thing and repaired the plugs.

[Grandad#3]

Check out the link at clark's-garage.com.

Speed and Reference Sensors - Checking, Replacement, and Adjustment

http://www.clarks-garage.com/shop-manual/elect-19.htm

Cheers,
Larry