'73, 2.0, engine temp sensor relocated?
 

I have a '73, 914, 2.0 engine 'barn find' that I can't seem to get running. Have checked out a lot of parts by swapping with my good running '74 2.0.

I noticed that the engine temp sensor that is usually in front of the #3 cylinder has been relocated to just behind the #2 cylinder. The hole where the sensor should have been is plugged with a bolt.

Is this a common fix for stripped threads or other problem? Or could this be the source of my non-running problem?
Thanks

Are you referring to the engine temp sensor or head temp sensor? Sounds like the head temp sensor that is used by the fuel injection system.

It's possible that the engine was converted to carbs at one point and so it wasn't needed and maybe plugged (even though it would not need to be plugged).

I'm really not sure how relocating this would affect engine performance but maybe the sensor is bad. If you are running with fuel injection, a bad sensor will prevent the engine from running - this is a $20 fix.

Use #3

C

You are correct, it is the head temp sensor. Should be in front of the #3 spark plug, but instead a bolt is located there (plugging the hole) and the sensor is located on the opposite head, behind the #2 cyl.

Could someone have replaced the left (driver side) head with a head from the pass side, therefore have the head temp sensor on the wrong side?? Or stripped the threads so they relocated the sensor the opposite side?

I tried shorting the sensor input lead to the battery (neg terminal), but that did not affect the poor running condition.

1. Has anyone else ever heard of moving the head temp sensor to the opposite head?
2. Would that make any difference, provided it is the correct sensor and working properly?
3. Could this be the source of my problem with poor running eng?

#3 will tend to run hottest because of the layout, oil cooler etc. There is a reason the temp sensor was put there. Nothing on the car that was not well thought out(except for putting a rubber plug in drain at bottom of hell hole and the plastic fuel lines, near as I can tell)

Someone put the heads on the wrong side. It happens from time to time. It shouldn't make much difference to the running of the engine. I doubt it is the source of your poor running problem.

--DD

The 2ltr that I bought had the heads switched by the PO, consequently the TS2 is on the wrong side.

#2 may run as much as 30 degrees cooler which may delay the TS2 signaling the ECU that the motor is fully warmed, but after warm-up there will be no performance differences.

My 2ltr warms-up great and runs like a champ...someday if I ever take this motor apart, I'll switch the heads.

You have done the most impt. check by grounding the TS2 lead which simulates a full warmed-up engine to the ECU....if your engine still runs poorly after the engine is warm, you've have other problems.

Thanks everyone for the help! I have an extra head temp sensor, so I even tried connecting it to the ECU lead (not installing the new sensor), and grounding the sensor to the body to see if that affected poor running. It did not help.

Still running way to rich.

I will leave the sensor on the driver side until I get it running well, then may move it back to the #3 cyl where it belongs.

Next project is to check injectors, and if they appear clogged, stuck, will switch the injectors from my '74 2.0 and see if that fixes it. Thanks again!