90 renix to 98 HO swap coolant sensor relocation

[Legendaryfish35]

Hello, currently in the middle of a swap in my 1990 XJ swapping a 98 High Output into it, I am keeping the renix intake and exhaust manifolds and reusing all the renix sensors. I am currently stuck as the coolant plug on the new 98 block is completely stripped so I am struggling to remove it, is there anywhere else that you can put the coolant sensor from the renix block without removing that plug?

 

[RCP Phx]

Drill it and use a easy-out to remove it!

 

[Marcass]

Probably too late for my reply.. but for the next guy.. I would avoid drilling that simply because it is a sensor, meaning the extraction will not be performed as usual. If you have thick enough bits/extractors.. knock yourself out. You are risking components/contaminated material into your block.

Here is your ultimately simple solution. Cut the wires off the old sensor and leave it. Watch for any leaks/seepage since you probably went primal on it.
Get thermostat housing from any HO. Will directly bolt to your RENIX head. That is where the temp sens was relocated. Make proper electrical connections from stock harness and provide yourself with a fresh sensor. Year matching does not matter. They carry the same thread pattern.

 

[Unclewolverine]

I'm not sure on renix but I thought he was talking about the early ho gauge sensor port on the back of the head. Some of the post 97 engines still had the port, but had a pipe type plug since the post 97 temp sensor in the t housing was dual function.

 

[Saudade]

Well, if the OP ever decides to return, perhaps we'll get some clarification.

There are 3 "Coolant temp sensors" on Renix. One in the block, just above the engine mount, one in the head near the very rear, and one in the radiator.

The one in the block does feed the ECU to control fuel pulse. When the HO's came out, this sensor moved to the t-stat housing. On HO blocks, the hole is there but has a pipe plug in it. There are actually 2 plugs (not the freeze plugs), one for the old sensor, and one for a block drain.

The one in the rad controls the electric fan and is a simple switch. Coolant gets too hot, fan kicks in. HO's moved this to the T-Stat housing as well. So the one sensor provided to the ECU for fuel and fan control.

The one on the head is for the coolant temp gauge/light in the cluster. Temp variable resistor if cluster has a temp gauge, simple temp switch if warning light. This remained until '96 when the XJ completed the transition to ODB II. After that, the one sensor in the T-stat housing provided coolant temp input to the PCM. The PCM then controlled fuel impulse, fan control, and gauge display.

Back to Renix , neither the one in the head nor the radiator provides any input into the ECU.

Renix


HO