Temp Sensors and cooling in general

[MrBill]

Once my MS2 is delivered via linuxman51, it will be time to wire up my car. I have a few questions, and need to make a few purchases, and do not have the car near me to look.

The temp sensors, the intake one has already been put in the car via previous owner. But the coolant one i dont know about. Does the coolant sensor screw into the top of the thermostat like the others I have seen? On DIY autotune, it seems they use GM sensors, are the threads the same? Should I tap another hole so I have my temp readout on the dash, but also so megasquirt can have it?

What kind of thermostat does my volvo have? Can I get a colder one, like a 160 or somethin?

Edit: if you dont feel this should be in aftermarket management, move it, i debtated which one it needed to go in.

[ovlov760]

On my 530 head there are two coolant sensors, one is for the gauge and the other is for the ecu(sensor closer to the firewall). I take my CLT readings from the one that went to the ecu. The '82 240 might be different? dunno.

[MrBill]

On my 530 head there are two coolant sensors, one is for the gauge and the other is for the ecu(sensor closer to the firewall). I take my CLT readings from the one that went to the ecu. The '82 240 might be different? dunno.

Ah, its on the head... I'm not sure if the old ECU even cared about temps, I know nothing of kjet. Well thanks for the info, I guess ill be waiting till i get home unless anyone else knows.

[ovlov760]

Ah, its on the head... I'm not sure if the old ECU even cared about temps, I know nothing of kjet. Well thanks for the info, I guess ill be waiting till i get home unless anyone else knows.
They are all hidden under the intake manifold in the head.

[The Aspirator]

Your K-jet car will not have the proper temp sensor, LH cars do though. K-jet will have one going to your dash gauge, so you just leave that alone. Then you go to your auto store (or order online) a temp sensor for an '85-95 volvo, I assume they're all the same. You might have trouble threading it into the head, I know lots of the k-jet heads are different, some work perfectly, others can take adapters. I don't think I've had to drill/tap anything yet, and I've done it to a few K-jet heads now.

What's an intake temp sensor doing there from the previous owner? What did they use it for? Just make sure it's the proper open element type (not solid brass, reacts too slow), and that it's preffereably in the cold side intake pipe, not in the intake manifold itself because that can lead to heat soak problems.

[ovlov760]

What if he went with the GM CLT sensor? It's cheaper, but I have absolutely no clue if it threads in. Are there any other good places for a CLT sensor besides the head on k-jet?

[The Aspirator]

The only other place might be the two vertical humps on the very back and very top of the B21 block, they're usually filled with K-jet temp sensors and thermo time switches and junk like that. Dunno what the threads are though.

On a related note, I broke a fairly new coolant temp sensor today, they're filled with this weird very white fluid.

[MrBill]

Okay, I do have an 86 wagon parts car that I'll use the temp sensor from. Ill report back later if the thing does not thread correctly.
The previous owner (turbo16psi) was in the middle of converting it to a electromotive tec2 when I guess he gave up.
It has a b230f manifold and new fuel lines, an 850 tps, and the temp sensor is in the manifold. If this is an issue, I dont think ill remove it, ill just put a new one in after the intercooler (ya know, no way to plug er')
Todd is a smart guy, I am sure he did it correctly. And I have a question about this heatsoak stuff. How can a sensor that detects heat.... heatsoak? I know only some of the people have problems with it, and I think there might be something else. I mean, once fresh air moves through it, it should register that, not something else. Ya know?

[The Aspirator]

Heat soak is mostly trouble during hot starts. Say you bomb out to a grocery store, shut the car off, then start it up again in a few minutes. The sensor will read way hotter than the actual intake air for the first few seconds, and might screw up your fuel calculations during starting, causing it to not start. I've never had this problem, but others have posted about it.

[MrBill]

Heat soak is mostly trouble during hot starts. Say you bomb out to a grocery store, shut the car off, then start it up again in a few minutes. The sensor will read way hotter than the actual intake air for the first few seconds, and might screw up your fuel calculations during starting, causing it to not start. I've never had this problem, but others have posted about it.

Ill look into this, on a related question, what is the coldest thermostat you can get for these cars? Autozone had a 180 degree, I was hoping for a 160:)

Edit: i looked on sam's site and its the same.. blast!

[The Aspirator]

180* is fine (82C) that's what I've been using on my engines, you don't want it tooooo cool.

[ovlov760]

180 is what I use. A couple people use 160 but I do not know where they got them.

[Sinbad the Sailor]

http://www.autopartsauthority.com/oemmakes/volkswagen~Lambda_Idle_Sensor~oemparts.html

and look in this thread

http://forums.turbobricks.com/showthread.php?t=28672&highlight=ms+install

I have the sensor and will be installing it in a k-jet head and will let you know how it goes.