sensor location at rear of the block (water temp sensor)?

i was finishing up my b16a swap and i ran into a problem… i have a green connector at the rear of the block with what looks to have a long water temp sensor attached to it. i think there is already one on the block but it has a broken socket. does anyone know where this sensor is in the rear of the block? does the b16 even have one of these? Pics would be PERFECT!!!

i’ve looked and looked but haven’t found any helpful info on the subject. thanks!

the green sensor is what i’m talking about. the b16 has this plugged off with a hex cap. is that normal? what does that sensor do?

That is the coolant switch. It was on the block of the B18A but they moved it on later engines to the thermostat cover. If you didn’t get the cover with the B16 then you can put the switch it in the same location as the B18A.

i’d like to put it there but i don’t think i have an allen key large enough to fit in there :frowning: maybe i should try finding an obd1 water neck. thanks for the help!

you dont even need the whole neck. just the thermostat cover where the hose connects. that will give you that sensor bung you want:whisper:

oops, i always referred to that housing as the water neck. that’s what they are called in hotrods… i guess it stuck with me. i guess i’ll look for one. thanks!

You can easily find the hex key “socket” from a Harbour Freight type store. I bought mine in a set and it has the correct size in it for like $10. It’s either a 14 or 17mm size (it’s been a while since I used it). Or you can go the waterneck method as stated by others, but you will need to find the sensor and connectors too if you don’t want to rigged a connection.

Before you guys get WAY off base…

http://www.g2ic.com/forums/showthread.php?t=41506&highlight=ect

I’m blown away at all the ECT related questions recently…

In addition to that post:

ECT Switch
-located on the back of the block on 90-91 b18a’s
-located on the thermostat housing on 92-93 b18a’s (and many other b series)

ECT Sensor
-located on the side of the head (cyl #4 side).
-location is slightly different on vtec heads as the vtec solenoid takes up some extra room. But it’s still on that side.

Gil, is that photo of your stock b18a? That “new and improved location” will not work properly.

Is your b16a 89-91 or 92-93?
See the ECT Switch in your picture (the unit w/ the black rubber “booty” on it) does your b16a have that?

If you look closely you will see that the sensor is located where one of the upper alternator bracket bolts should go. This is a common location for a Knock sensor when building an LS/VTEC engine. Someone has added a knock sensor to that location. If you need one, then replace that one. If you don’t then you can either remove it and put a bolt in there or leave it alone.

no no, that’s just a picture i lifted off the net. i am talking about the green sensor that is in the pic. my b16 has that location blocked off. my engine did not have one of those installed anywhere on it… ? colin, it does have the sensor with the black boot. i am wondering about it since i recently got my car running and noticed that the fans do not come on. i jumped the sensor (one with green socket) and nothing happened. i guess i’ll start looking for a water neck and extend the green plug to the neck. or maybe my b16 wasn’t meant to have one? i dunno…

I can’t say for sure Gil. I did a little looking into it and it’s very possible that that motor simply does not have it. It may be something which only came on cars setup for a/c and I don’t know enough about the jdm b16a’s to say if that could be a factor.

Can you pull the one off of your old motor? I would be surprised if it wasn’t the same threading.

Remember, we are now talking about the Engine Oil Temp switch - not any of the ECT units. I’m not going to go into the nitty-gritty… but you should. Helms 23-102.

The “black boot” sensor is the ECT switch. That should wire up just fine w/ your stock wiring if you have a 90-91 and you’ll just have to re-route the wires if you have a 92-93.

“Jumping” the switch does absolutely nothing, or actually it might be able to cause damage, I don’t know for sure. Remember, the thing IS the switch, it’s telling something else when to turn on/off.

[QUOTE=Colin;1895430]I can’t say for sure Gil. I did a little looking into it and it’s very possible that that motor simply does not have it. It may be something which only came on cars setup for a/c and I don’t know enough about the jdm b16a’s to say if that could be a factor.

Can you pull the one off of your old motor? I would be surprised if it wasn’t the same threading.

Remember, we are now talking about the Engine Oil Temp switch - not any of the ECT units. I’m not going to go into the nitty-gritty… but you should. Helms 23-102.

The “black boot” sensor is the ECT switch. That should wire up just fine w/ your stock wiring if you have a 90-91 and you’ll just have to re-route the wires if you have a 92-93.

“Jumping” the switch does absolutely nothing, or actually it might be able to cause damage, I don’t know for sure. Remember, the thing IS the switch, it’s telling something else when to turn on/off.[/QUOTE]

hey colin I know you probably answered this and I was wondering if you could tell me what all three of those sensors are sorry I am pretty sure you said the green plug was ect and the booty one is for oil temp or something if I am wrong please fill me in sorry to jump on here and changed subjects but does anyone know how to fix a code 20(my car is a 90 db1 with a 95 b18c1 with a p72)

The one with the black boot is the ECT swtich, the green connector is the oil temp sensor, and the one prong connector is Oil pressure switch.

i ran into that same problem when i swapped a 99 b16 into my gsr, i plugged the sensor and left it hanging, gotta go a big enough allen key is remove and replace it haha

thank you appreciate it. plus it wasnt the tps sensor I have no dang clue whats up everything is connected how its supposed to be I bout a boomslang harness a while back and wrote down what pins go to what so I doubt thats wrong does anyone know where the eld is on the 90 db1