Hey all... My fuel rail started spraying fuel all over the intake manifold on initial start-up. It's coming from the front crossover pipe on the fuel rail, so I gotta pick up a set of o-rings for it. I figured it would be a good idea to take care of it before something really serious happens.

Anyway, with the plenum off, I was reminded of a question I had long ago that never got answered. Looking at the MAT sensor, it seems to be practically identical to the Coolant Temp Sensor mounted in the front of the manifold. Does anyone happen to know if they're the same thing? The connections look the same, and the sensor itself looks the same, but I dunno. Thanks. - John '89 L98

 

Looking at them, I noticed a couple of visual differences.
- the MAT sensor has diamonds cut into hex portion of the sensor. the CTS is a solid hex with no cutouts.
- the MAT sensor seems to use a tethered check ball arrangement at the probe end, while the CTS has a solid metal probe(no visible openings.

the information I found, indicates they both have the same output resistance vs measured temperature. However, as the CTS will have to measure higher temperature than the MAT will ever see, I would have to think there is a difference in thier operating ranges. and as indicated above, the differences in thier probe ends would seem to indicate differences in thier actual operation.

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He who hesitates,... is lost!

 

Hmm... I have three TPI Camaros ('86, '88, and '89) sitting at the house, and all three examples of MAT sensors do not show the features you're describing. In fact, they look exactly identical to the two Coolant Temp Sensors I pulled along with the spare one I have in the garage.

Maybe I'm confused here... I pulled my MAT sensors from the back underside of each Camaro's plenum. That's where they're supposed to be, right? With a black and yellow wire going to them, right?

My CTS looks exactly as you described ("solid hex with no cutouts... has a solid metal probe(no visible openings.)") But, all the MAT sensors I have do not have "diamonds cut into hex portion of the sensor" or seem to "use a tethered check ball arrangement at the probe end." They are identical in looks, feel, and connector type. Now I'm even more curious.

Anyone else have something to add? - John '89 L98

 

My stock CTS and MAT sensors looked exactly the same and that's w/out the "tethered check ball arrangement " or "diamonds cut into the hex portion of the sensor".

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92 Z28 L98 350
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Ported and polished heads, ported stock TPI base, ported plenum, Comp Cams XR270HR-10 cam (lift .495/.502 duration 218/224 lobe separation 110), Edelbrock TES headers, LT4 valve springs, Crane AFPR, Flowmaster catback with LT1 style tips, MSD coil & wires...

"Take that auto, drop it in first, hold the brakes, stomp the gas and grin from ear to ear! :-)

 

I just replaced both my CTS and MAT. I got them a local GM dealer, and they are the same. While you have that off, you might as well do the MAT relocation

 

Hmmm,

When I pulled my MAT sensor to do the relocate mod. it was I described it(diamonds cut into the corners of the hex, and a caged checkball at the probe end). Mind you, the previous owner of the car had done some wierd stuff to the car(such as gutting the cat((Ugh!)) and then welding it back to the intermediate pipe). Anyways, if that was not the exact replacement, it at least gave the correct output ohms for the current temperature.

Has anyone else ever had a sensor as I described above. Can anyone tell me if it is actually a "correct" thermistor(it appears to work fine even with the relocation to the airbox lid).

I guess the best solution would be to go to the dealership and ask for a MAT and a CTS. If the p/n is the same, they're interchangeable.

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He who hesitates,... is lost!

 

Thanks Freeze, for letting me know they're the same part # from GM. 88IROCs, I'm not sure as to what it might be that you have as a MAT sensor. Who knows? It might be a sensor from another vehicle that serves the same function. As long as it works.

And I did end up doing the MAT relocation tonight. It seems GM even had a nifty little spot already picked out for me on the driver's side of the air intake piece. A couple of splices, a foot of wire loom, some paint on the brass hex part of the sensor, a little tucking and hiding, and voila! It looks as if it came from the factory. Thanks again, guys. - John '89 L98

 

There is no "tethered check ball". This is the thermistor in the end. As for your sensor 88Irocs, it may just be an aftermarket replacement. I remember I changed the Mat sensor in my grand am with one from advance auto and it was different than the factory one.

James

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If the women don't find you handsome they should at least find you handy

 

88irocs i have an 88 and the mat and the CTS are identical. you could also have the sensor from the v6 in there maby? i kno wthe sensor on the 6 has the same plug but the prob end is open and i think plastic as for the v8 its solid brass just like the cts? i donot know however if th ecomputers on the v6 and the v8 look for the same output voltages so i dont know if this is even a possability


-Stell

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1988 IROC 305TPI MINT!!
Mods= Accell SuperCoil, MSD 6A, Ported Plenum, No MAF Screans , K & N, 160 Thermostat+ Temp Switch
And Always Trying To Go Faster