What the hell happened to my coolant temp sensor?

[Cody]

So, I recently acquired my first true e30, a 3/87 build 325is, and naturally had a few issues to deal with.

Had the 'surging' idle problem, and after replacing all of the vacuum hoses, I purchased the ICV, o2 sensor, and was set to order the coolant temp sensor for the fuel injection.
I saw there were two different version, one with blue and one with tan, so I removed the connector to find a 3 prong black sensor...

I dont have the bosch part number in front of me, but it was the temp sensor that came out of a 750 or 850 of the same vintage...

There was also a pair of wires running from it to a hella relay that are definitely not stock.
From the relay, in addition to the two running to the temp sensor, there is a lead going to the starter, and one to ground,,, almost like a cold start modification.

so... anyone ever see this. It is a one owner car and mostly had it serviced by the dealer, or Berkeley motor works.

Here is the link to pictures:

http://imgur.com/a/7ipk1#4

Thanks for your help, I was waiting to make a proper introduction when she is running properly and more dialed in, but just need to get the damn thing running first.

Also, still have idle problem after ALL vacuum hoses have been changed, the o2 sensor yet to be installed, and ICV is on the way.

Regards,
Cody

[paperplane94]

Is it a 3 pronged sensor now?

If it is I do recall someone else with that same problem, or was it you?

[Cody]

Yea, It has the 3 prong sensor from a late 80's 750/850 v12...

And it was not this car with the problem before, so hopefully it is something that someone else has experienced, or documented.

[paperplane94]

AHA, I found the other guy:
http://www.r3vlimited.com/board/showthread.php?t=252895

Bit of an unhappy ending if you ask me. Another theory is that it was sold as a kind of mod by some ebay seller or the like.

[Cody]

Yea, I just don't know.
The guy definitely did not do it as a performance mod.

The only thing I can guess is that looking through the records there was a problem cranking/starting a while back, and some mechanic may have modded it as some sort of cold start thing since two of the leads end up at ground and the starter... making a circuit when cranking the car to give more fuel.

As long as the car will idle after changing out the O2 sensor and the ICV, I don't really care if it's all rigged... just wanted to eliminate all of the possibilities of 'hanging' idle.

[paperplane94]

Ah, that sounds a little more plausible.

[maxlax7910]

I had this on my IX. Removed and replaced injector harness with used one, along with new coolant temp sensor. I played around with removing the relay before I did anything.

I think it is something for cold start. My ix cam from Colorado.

[AndrewBird]

I wonder if this this was part of the cold weather package that came on some cars. OP, run your VIN through here and see if it was an option:

http://www.r3vlimited.com/board/showthread.php?t=264057