1G How many coolant sensors on a 1G Turbo DSM?

[XC92]

Hi all, hope you've had a not too bad winter and are enjoying the early spring weather.

It's almost warm enough around here to work on the car w/o freezing and I've continued to have idling, warm engine startup and excessive gas consumption issues plus an exhaust/gas smell that I suspect are due to a faulty coolant sensor.

Thing is that 1G Turbo DSMs have multiple coolant sensors and I'm wondering what they all are and which one is likely the faulty one if it is indeed faulty.

Best as I can tell these are the ones:

1. At bottom of overflow tank to light up dash light if coolant is running low
2. By thermostat to tell ECU current coolant temp (2 wire)
3. Also by thermostat...connected to dash coolant temp gauge? (1 wire)
4. A/C switch, located...?
5. Fan switch

I'm guessing that probably some of these are the same sensor, and maybe I even missed a sensor. Yeah I can look it up in the FSM but I slept poorly last night and can barely function, but yesterday the car acted up again and I'd like to address this ASAP.

But do I have it pretty much covered as far as all the coolant-related sensors and if a faulty one is causing these issues, is it most likely #2?

If so, OEM or is aftermarket ok and if so which one(s)?

Finally, why are some of the vacuum hoses connected to #2 & #3 if they're already feeding data to car electronics? Double duty sensors?

 

[jdxnc]

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[XC92]

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Thanks, so, likely #5 (from your image, not my list), if it's a bad sensor, right? And, this explains what the various sensors & valves are, so many that it can be confusing.

OEM part appears to be out of production, so any aftermarket ones you'd recommend?

But I could have sworn that there were 2 vacuum valves, with 2 pipes each. Am I thinking something else that's near the thermostat but not the thermostat? I redid it all last fall and promptly forgot it.

Also, my A/C no longer works, could it be because #6 is faulty, or likely something else? I mean it puts out air, just not cooled air. Unrelated but just wondering.

 

[1990TSIAWDTALON]

I run Standard Motors TX32 for that #5 sensor (because Standard Motors is located in my town and I have relatives that work there).

 

[XC92]

I run Standard Motors TX32 for that #5 sensor (because Standard Motors is located in my town and I have relatives that work there).

Thanks. Is NTK ok too? RockAuto has both and several others.

And is this a common cause of the symptoms I described? Of course only an actual diagnosis would tell me if this is it, but just wondering.

 

[1990TSIAWDTALON]

A bad temp sensor is usually associated with a no start or hard to start condition, so it is a very important sensor. I haven't used an NTK temp sensors although I think I have 1 or 2 Knock sensors that are that brand (it kinda sounds familiar).

 

[XC92]

A bad temp sensor is usually associated with a no start or hard to start condition, so it is a very important sensor. I haven't used an NTK temp sensors although I think I have 1 or 2 Knock sensors that are that brand (it kinda sounds familiar).

When cold it always starts, no problem, and idles more or less ok. But after it warms up it idles rough and doesn't always start up well unless I feather the gas pedal. Also poor gas mileage & gas/exhaust smell.

Btw why do we still call it the gas pedal when it's actually the throttle pedal, which indirectly controls gas flow via sensors and the ECU? Or am I the only one who still calls it that?

 

[1990TSIAWDTALON]

I am 60. It is a GAS PEDAL to me. Not the accelerator, not the foot feet, I am of the age (a better way of saying I am old) that I remember the starter "button" on the floor.

 

[XC92]

I am 60. It is a GAS PEDAL to me. Not the accelerator, not the foot feet, I am of the age (a better way of saying I am old) that I remember the starter "button" on the floor.

Hey, as you can guess with me being the original owner of a '92 DSM I'm not that far behind, in fact just a few months from that threshold. Almost makes me wonder what I'm still doing messing with cars let alone a 25 year old's car.

But yeah, fewer syllables for sure, but it's not a gas pedal dammit Jim. It's a Throttle Opening Mechanically Operated Control Actuating Pedal, or TOMOCAP!

 

[1990TSIAWDTALON]

Love it!
You gotta be our age to know who the hell "Jim" is!
"But dammit Jim, it's a flip phone not a communicator, now BEAM ME UP SCOTTY"!

 

[XC92]

Love it!
You gotta be our age to know who the hell "Jim" is!
"But dammit Jim, it's a flip phone not a communicator, now BEAM ME UP SCOTTY"!

Heh, all wisdom relates to Star Trek. Anyone under 40 is just a child.

Btw just tried to test the temp sensor. Way too much crap in the way to get to it w/o cutting my hands. It's too cold and rainy today to tackle it but tomorrow I'll remove whatever needs to be removed to get at it. But I'm guessing that it's bad.

I mean she's a-got to a be a-malfunctioning Jim! I cannot a-say what else might a-be a-wrong wit her! I replaced the dilithium crystals last week!

 

[1990TSIAWDTALON]

Well that shit worked last week Scotty...............

 

[XC92]

Well that shit worked last week Scotty...............

Well slàinte mhath to you too, Jim!

 

[danl]

Thanks. Is NTK ok too? RockAuto has both and several others.

And is this a common cause of the symptoms I described? Of course only an actual diagnosis would tell me if this is it, but just wondering.

NTK EF0099 is likely the oem manufacturer.

 

[XC92]

NTK EF0099 is likely the oem manufacturer.

Hmm, interesting. Looking at the images of each on RockAuto, the Standard Motors TX32 actually looks somewhat better made. But it's probably six of one...

 

[danl]

NTK is the sensor side of NGK. I have the NTK temp sensor in question in hand. I can not tell the difference between the original in my car.

I am very happy with the ISC I got from standard motor products. You do you.

 

[XC92]

Always hated that expression. I mean, what else am I going to do?

 

[danl]

Buy both. Having a spare is never bad. The prices aren’t horrible. My oem works and I bought the NTK as a spare because, dsm.

 

[XC92]

First I want to confirm that it is in fact bad. Perhaps it's ok and the wiring is bad and something else is bad. But based on all that I've read it's at the top of the list of likely culprits. I'll test it, and maybe do that silly LED to read the OBD1 code morse code thing to see if a code has been thrown (although the CEL hasn't come on but for all I know it too is bad). But I have to remove a bunch of stuff to get to it first. DSM are packed tight in the engine bay.

 

[Jk's97DSM]

NTK/NGK is the best.