I need to test and potentially replace the CHTS. I see the lead to the sensor has a 2 inch long red "torpedo" looking device between 2 black connectors. It looks original as the 2 connectors are solid black with VW stamped on them. Anyone know what the red torpedo is and how the 2 black connectors come apart???

Steve

The CHT sensor should be a small 'plug' with a single black wire coming off of it.

It's a resistor. I forget the value, Brad Anders' D-jet webpage will have the number. (240 ohms??) http://members.rennlist.com/pbanders

The plugs just pull apart. The sender wire and connector unplugs from the plastic housing on the resistor, and the resistor unplugs from the plastic housing on the wiring harness.

--DD

the torpedo is likely a inline resistor, used on the 1973 model 2.O liters. this added resistance which made the enigne run a bit richer than without.

Yup 240 ohm.

If yours is a stock 73 2.0 EFI, then you'll need the resistor in line with the -017 CHT.

Otherwise 74-76 2.0s use the -012 CHT with no resistor, which are still readily available from many P-car/914 parts sources.

Rich at HPH may still have one of each NOS for the 73 2L.

nope...none left. just the 012.

if you use the 012 on a stock 73 2L, do you still use the resistor?

Factory installed 270 ohm resistor for 73 2 liter. Early 2.0 engines used 037 1.7 ECU and the resistor corrected idle mixture.

Old thread update. My "red torpedo" cleaned and updated resistor along with a factory replacement from Auto Atlanta.

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Nope....

The 012 CHT had a cold value of something like 3200 Ohm

The 017 was more like 1600 ohm cold That's why they added the 270 Ohm resistor.

If you use the resistor with the 012 you will be making it richer still.