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IL KIM
01-07-2007, 08:25 PM
I have used this tee (circled in pic) to keep both the factory temp sensor and to tee in an aftermarket thermocouple sensor (for gauge). Is there another set-up, kit, or nicer fittings (brass?) that allow for a cleaner package? Would still like to have both sensors hooked up. Been looking through archives as well... Thanks.

PaCemkr86
01-07-2007, 09:29 PM
im pretty sure the factory one only turn on a light.

Keller
01-07-2007, 09:47 PM
Holy gargantuan pile of...you just added weight to your car! :slap:

Check information on this site. One sensor is only for the TEMP light in the dash. The other is for the temp sensor to the ECM. The dummy light sensor can go. The ECM sensor must stay.

No need for a 2 lb. tee to make all three stay there.

IL KIM
01-07-2007, 11:26 PM
I know; what a mess; but I wanted to keep all the factory idiott lights working (not to say the only other person would be one), but, hey, a light could be a failsafe... Infon on sensor locations must be incorrect and only shows one of the 2 sensor locations on the intake manifold.... Also, I'm not sure which one is the light and which is the input to ECM.

And if I get rid of the sensor for light, I need to do something to the wire? :ow:

Keller
01-08-2007, 03:59 AM
The wire can just be tucked away, or back into the harness.

Since the temp is readable on a gauge, you should be checking it periodically, anyway. The oil sender for the light gets tee'd in, since it is more critical to know of oil pressure loss immediately.

IL KIM
01-08-2007, 01:14 PM
Thanks Keller.
I look at the gauges quite often, and yes, the oil senders are teed in.

How do I keep the temp idiot light functional as well, without this gargantuan pile?

IL KIM
01-10-2007, 10:36 PM
OK; so no-one is running the stock temp sensor and an aftermarket gauge sensor?

I had a Probe GT that overheated on 80+ degree summer days after being driven about 45 minutes on the freeway. I would shut the engine off and coast to keep the guage down whenever I could and it got to the point I would call the dealership and coast into the bay while it was acting up with them waiting at the entrance with the door open. They couldn't find the root cause, and I ended up putting in a manual fan switch, that I would turn on whenever I noticed the temp gauge was rising. I must say the idiot light also helped once in a while so I would reach for the fan switch instead of having to pull over and wait it out. The person I sold this car to, took it to a dealership in California, and trusted in them that the radiator was bad, and had them switch it out, as well as unwire the fan switch. The motor burned up.

So I'd like to keep the idiot light and will at least change out the black pipe to brass if I can find the parts, as I think the black pipe may act as a heat sink. If anyone has a different setup, info would be appreciated. Also, the link here //www.gnttype.org/maint/sensors.html shows one of the 2 temp sensors (27. Coolant Temperaturehttp). Is the other one missing in this pic?

Which one is for the ECM and which is for the idiot light?

PaCemkr86
01-11-2007, 12:16 AM
the one for the ecm is on the drivers side and the one for the light is on the passenger side



Phil

Praezision
01-11-2007, 02:05 AM
EVERYTHING MECHANICAL HAS AN ELECTRICAL EQUIVALENT :stir: - and it's usually 99% lighter! :woot:

You could use the stock ECM temp sender (resistive/temp) into a buffer (so it doesn't affect the ECU's readings) then into a threshold (comparator), which drives a bipolar or FET which drives the stock lamp... can likely be done with one LM324 and either a 3904 or 6 depending on which way that lamp is driven.

The ECMs read the 'thermistor' (the actual ECT sensor) by setting it up in a voltage divider. The ECT sensor is the 'lower' leg and the upper is internal to the ECM and is a fixed value. What the ECM reads voltage wise is the non-grounded pin of the ECT sensor.

Would be a cool lil novice project! :innocent:

:flame:
Phil

IL KIM
01-11-2007, 12:13 PM
Thanks Phil and Phil. Phil; you went over my head. I knew there was a reasong to become an electrical engineer in colledge rather than a mechanical engineer. Sounds to me like RJC racing or other company should put something on the market. :faint:

At least I'll move this setup over to the lhs and not tee in with the ECM sensor.

chrisgarrett
01-11-2007, 12:41 PM
I just screwed my temp gauge sensor into the ds of the block. I don't have a pic of it, but here's the oil tee if you are interested.

Praezision
01-11-2007, 03:02 PM
Phil and Phil

Sounds like we could be a comedy duet... I'm sure if you got us together that's what we'd be!

:slap:

Praezision
01-11-2007, 03:06 PM
Ah... and on the oil tee... I've done the same, except I like to use stainless fittings if at all possible. The brass *may* :quote: break. If anything I would use the SS fittings for the Male-Male couplers. The SS fittings are sometimes a PIA though since they're not "squarey" :quote: so getting a wrench round em in tight spots is sometimes a PIA. Hit up McMasterCarr for all that junk!

Phil

IL KIM
01-11-2007, 08:51 PM
Chris; very nice. Looks like a swivel setup? I already have a tee for the oil sensor. Are you saying this setup might work for my temp sensors? If so, Where did you get it? What is a "ds"?

Phil, I can imagine what getting you and Phil together in one bar! Problem with McMasterCarr is I need to tell them what thread size all this mess is. Would be easier to go to a HW store, but thanks!!!

PaCemkr86
01-11-2007, 08:57 PM
you could always wire up a hobs switch to your gauge and have it turn on your factory light... then there would be no T and you will still have the "idiot light"
and with the use of a hobs switch you can have it turn on the light at what temp you want



Phil

chrisgarrett
01-11-2007, 08:58 PM
ds means driver's side of the car. There is a allen bolt on the ds block that you can screw out and screw your temp sensor in. Then run the wire up through the firewall hole.

IL KIM
01-13-2007, 09:30 AM
Chris, reviewing your suggestion prior to picking one and I don't see any hex or allen fastener on the ds block. I got the block back yesterday from machine shop and ds has engine mount holes, dipstick hole, and a hole for the small-hex-cap/bolt drain plug. Nothing that at thermocouple sensor could screw into... :nope: What am I missign.

chrisgarrett
01-13-2007, 10:21 AM
Chris, reviewing your suggestion prior to picking one and I don't see any hex or allen fastener on the ds block. I got the block back yesterday from machine shop and ds has engine mount holes, dipstick hole, and a hole for the small-hex-cap/bolt drain plug. Nothing that at thermocouple sensor could screw into... :nope: What am I missign.

I'm not sure. The small hex hole you describe is probably it. My temp sensor screwed right in.

chrisgarrett
01-13-2007, 10:26 AM
Here's a view from under the car.

Praezision
01-13-2007, 12:56 PM
I believe that is actually the "plug" for the waterjacket to remove all the water when doing the freeze plugs. Usually, there's some sort of brass plug in it - think it's like an 1/8NPT or somethin.

chrisgarrett
01-13-2007, 01:06 PM
My temp gauge always shows the same temp as the Scanmaster, so it should be an okay place to install the sensor. I always pull it out when I want to drain the block.

Keller
01-13-2007, 02:31 PM
Ahh, yes. Forgot about that. The picture is rotated compared to reality. The head and header are on the left in the picture, engine mount on your right. Transmission would be downward. A local shop does the connection this way always. You will retain the warning light if done this way.

Great suggestion! :tup:

IL KIM
01-13-2007, 10:13 PM
Chris, every picture you post shows your engine is immaculate! Yes, this where the is small brass drain plug goes. My thermocouple has a 1/2 male pipe thread - far too big to do what you did. I like it though. Also looks like you changed your motor mount to aftermarket. I think a trip to the hardware store to reduce my 2lb steel mass to 1lb of brass is in order.

Keller
01-14-2007, 02:21 AM
Why not just get the right sender for the job?

chrisgarrett
01-14-2007, 07:28 AM
Why not just get the right sender for the job?

That's what I was thinking. Mine's a VDO. They aren't very expensive.

IL KIM
01-14-2007, 10:26 AM
There's nothing wrong with my sender or gauge, and the gauge I have matches others I have.... Is Chris' VDO or mine more accurate(?) If I just get the VDO sender, do I need a new guage or will it throw off my gauge? I need to go look at my gauges. Thanks for the pics and options.

chrisgarrett
01-14-2007, 12:30 PM
There's nothing wrong with my sender or gauge, and the gauge I have matches others I have.... Is Chris' VDO or mine more accurate(?) If I just get the VDO sender, do I need a new guage or will it throw off my gauge? I need to go look at my gauges. Thanks for the pics and options.

Call VDO directly: http://www.vehiclecontrols.com/products/vdo_heavyduty.htm

IL KIM
01-14-2007, 01:36 PM
Here is a pic of the plug the goes into the block on top, and my thermocouple sender on the bottom. Pic is lined up left/right to where the plug and thermocouple would rest against the block. Looks like it won't fit. Thanks.

chrisgarrett
01-14-2007, 01:40 PM
Here is a pic of the plug the goes into the block on top, and my thermocouple sender on the bottom. Pic is lined up left/right to where the plug and thermocouple would rest against the block. Looks like it won't fit. Thanks.

That thermcouple looks pretty sad.

IL KIM
01-14-2007, 03:20 PM
It's just 2 dismilimar metals sitting in coolant for 16 years. I'm sure a scotch pad will do wonders! Will let you guys know if I take the easy way out after visiting the hardware store...