head temp sensor wiring modification??
 

I have a 2 wire head temp sensor that I am going to replace as a matter of maintenance. Heres what I want to know. The installation process is quite simple but the wire and grommet is a pain. I want to install the new sensor in a manner that would make it a snap to put one in on the road if necessary. I want to use an insulated 2 wire connector in line between the head temp sensor and the grommet so I can effect a change roadside if the sensor fails. I would wire the old one (spare) with a connector of the same type so I coud remove the failed sensor with my slotted socket and replace it roadside. If the connection is clean and insulated would this cause a resistance problem for the sensor. Thank youany information greatly appreciated, thanks JL

Hey CaptainLewis,

I think it would be OK as long as you insulate the splice i.e. heat shrick?. I would worry about the elements though, it does get pretty exposed there.

The new updated CHTS rarely fails so I would not worry about "on the road" failure. Once you update it is good to go for many miles without trouble.

+1 most failures of cht sensors are intermittent anyway and wont leave u stranded, and you will get home to be able to diagnose the issue. Even if the sensor completely fails, you can operate the vehicle in "limp mode". Do a seach. It involves unplugging the cht sensor from the sensor strip on top of the engine bay, and plugging in a resistor in place of the sensor.

head sesnsor mod
 

when spiceing the wires can they be croassed or does it matter, I mean if the leads are switched does it make any difference, Thanks JL

You're going to jack up your car on the side of the road, take off the rear wheel, pop out the grommet, and install a new CHT sensor on a hot engine with your head and upper body up in the wheelwell while hoping to not wreck the speed and reference sensor wires? Not something I'd sign up for ...

The connector you're planning will be next to the cylinder head, so it had better be pretty heat proof.

And I vaguely remember reading that the car will run with the sensor wire grounded, albeit rich. That you could try on the plug in the engine compartment with a couple of alligator clips.

Agree with "dimeified".
If you feel you need a backup use a resistor into a plug, replacing the sensor. Use a resistor anywhere between 90 to 210 ohms (1 watt) would be fine. This will simulate head temperature above 210deg F (normal). If additional fuel was required for a cold, cold, cold start unplug the resisor for a few cranks.
Paul

IMHO, such modification would probably just add a weak link to an otherwise trouble-free setup.