temp sensor, plz help

[DJester187]

hey guys the k08 had 2 coolant thermosensors (temp sensors) and my ze only has one, on top of the left side of the engine after the fuel rails. my cel won't go off and the code always comes back. i have the two sets of wires (for the old sensors) wired together for now (based upon actual mazda wiring schematics), but they should be giving the ecu different readings. this effects my start up and stuff a little, and idea how to wire it properly as to stop this issue?

[TsiMiata]

You have to put that other sensor back in. The two sensors read completely different from each other. They have very different resistance characteristics. I have to do the same thing. What my plan is is to drill, spot face & tap the waterneck on the car. Your other option is to tear apart the engine and swap the waterneck from your K8 onto the ZE. There's no easy way out.

[mdavis]

More simply put - you know the flat spot on the coolant neck bellow the filler cap? On the K8 there's a hole there with a sensor in it and on the ZE it's just a flat spot.. You can wither swap the filler neck when the motor is out, and timing belt cover is off, and the IM is off, or you can drill and tap a new hole yourself. I did this and it took like 2 minutes (seriously) Just make you use take the rubber hose off the metal neck, and shole a cloth up there or something to drill into to get the aluminum filings out so they don't circulate around your engine I took the told sensor from the K8 into the auto parts store with me (jsut unscrew it) and they found an appropriate tap, and the tap instructions had the needed drill bit listed on it (as I recall, it was an odd size..) So just go home, stick a cloth up there, drill it, tap it, clean the shavings, and screw in the K8's sensor!

[DJester187]

wow! ok that was definately one of the best, and most comprehensive responses i've ever gotten off this site. i will definately try that, now 1) can i use just a regular drill? 2) is the location easy to get to if the engine is apready in the car, and lastly 3) if i were to completely drill into the engine some filings will end up inside it right? (perhaps you could post/email me a pic of where to drill, or just circle it on another pic or something. either way thanks a ton!!

[PATDIESEL]

You have to take that part of the coolant line off so that you don't get shavings in it then drill it out to the size of the sensor threads minus the threads, then tap (after guaging the sensor threads) it so that the sensor will screw down. It is a major pain in the butt. i think that it took me about 4 hours, best I can remember I ended up taking off the whole timing belt and everything in front of it. Also had to remove the intake. Then you can get to the pipe to remove the end piece to drill and tap it.

[mdavis]

I just got a metal drill bit in the size the tab directions said I needed. Yes, it's very easy to tap when the engine is in the car - I did. Here is a pic of mine: http://www.mkd.cc/coolantsensor.jpg (if that gives you an error, copy/paste the address into a new browser window - sorry!) As you can see mine leaked a bit, I just snugged it down a bit - Just make sure you take that rubber tube off the coolant neck underneath it and shove a cloth up there or something to drill into to capture shavings. Unscrew the filler cap, too so you can somewhat see what you are doing. Try to clean as much of the savings out afterwards as possible.. I don't know what they will do but I bet it's bad

<small>[ July 22, 2004, 07:36 PM: Message edited by: mdavis ]</small>

[TsiMiata]

I'm surprised it hasn't leaked on you. The threads aren't what seal it. The sensor seals against the spotface on the waterneck. If yours hasnt leaked yet it shouldnt in the future though.

[TsiMiata]

I just drilled and tapped my sensor today. Didn't go real well. Even with spotfacing the water neck it leaked. I ended up putting an o-ring on the sensor and countersinking the hole. That sealed it up finally. I took pictures and I'll make up a procedure with pics sometime this week.