so i bought a autometer water tep gauge and went to install it...just took out the stock one and put that one in..but now my car wont idle..it stays at 1500 rpm and wont go any lower..what im asking is where did you put ur probe at!..how do i get rid of the pre cat warm up for good..?..

thanx

Trevor

 

did u install another sensor or what?

 

i took out the stock water temp sensor and put in the auto meter temp gauge in there..thats it..

 

Did you take the sensor out from behind the water pump? If so, that is the water thermosensor. Put it back that it is very important and interacts with the ECU. Water temp sensor is the one on the block near the oil filter pedestal that gives the stock gauge it's readings.

 

ya thats what i did...!..damnit...the thermosensor wire broke too..so i guess im gonna have to order a new one..

 

yep, u replaced the worng one

 

sucks when that happends huh? haha. I hate that

 

That's why you look in the FSM or Haynes manual before doing something like this. Always be sure exactly that you're messing with before pulling it apart.

 

ya i was going to do it there but the size of the hole is tiny compared to the sensor i bought..the sensor that i bought is like twice the size as the stock one...
where did you guys put urs..if you have one and did you have to drill it bigger?

Trevor

 

Umm, I suggest getting a smaller sensor, not drilling a larger hole.

 

yea ... u always wanna try to do other things rather then cut, drill, ect .... cause if you ever need to go back to stock, your fucked

 

and all those beautiful iron debris running thru the cooling system...

 

thats why im asking what you guys did?...i dont want to drill..its an Autometer water temp gauge and the nut that came with it is huge..it fits perfectly in the hole on top of the water pump where that sender is..threads match perfectly too..but i dont think there is good flow and when i took that sender out my car wouldnt drop below 1500 rpm even at normal operating temp.

 

The flow in that location is fine. Your idle is high because the stock thermosensor isnt there and the ECU is defaulting to a set parameter.

Here are some solutions in order of best to worst in my opinion
1) drill and tap into waterpump housing (easy to do)
2) take out the stock temp sensor in the picture above and get an adapter fitting (readings will probably not be as accurate)
3) I think people have put the autometer sensors into the coolant block drain plug (search for it)
4) do it home depot racing style and get a piece of pipe and drill and tap for the fitting and then cut your radiator hose and insert between with hose clamps (not very accurate and will only read once the tstat has opened)

 

buy a gauge with a smaller sender

 

Hmm depends on the engine, on my N/A I just drilled and tapped the water pump housing.
On my S5 T2 engine the back of the water pump has two sensors.. one is used by the haltech, the other Is were I put the temp guage. Not sure what the other is used for normally on a FC though, might be for the electric fan in infront of the ac condensor? I'm sure someone will shime in and let you know weather it is ok to remove the second sensor (single wire), and put your after market sensor there.

But drilling and tapping the water pump is pretty easy.. the hardest part is getting the water pump off and on.

 

You can install it on the front plate instead. There is an allen plug. Driver side of the front plate, a few inches above the oil pan. Im not sure if its accessible if you have p/s and a/c. Mehcanical gauge with coated sending unit (like the autometer) is what I prefer.

 

That location is a branch, so it has virtually no flow across the sensor which slows the gauge's response. Not recommended.

If the new gauge's sensor won't fit in the stock location (don't use an adaptor for the same reason as above) then remove the water pump and drill and tap a hole on the back next to the ECU thermosensor.

 

Yes, you have few options.

To do it the "right" way, you remove the waterpump housing from the engine and have it drilled and tapped for the fitting you have. You have to test fit to be sure your new plumbing wont interfere with anything once back on the engine, too, and you have to be sure the place you drill has enough material to support threads. IT also has to be a clear path to the coolant.

A "cheat" to this, if you can do without your air pump (or dont care to modify the bracket at least) is to remove the airpump bolt closest to the alternator. Use the hole there as a starter, and drill all the way through, drilling and tapping to the size of your fitting. IF you drain your coolant the day before as well as remove the thermostat neck and thermostat, you can use a shop vac and small extension tube while this is being done to suck up most debris that might fall out the back side, and a small bit of debris in the coolant system won't affect anything anyway (you'd be surprised how much crap is trapped in "dead spots" in the blocks I take apart).

Now just screw in the sensor from the front, run your wiring, and put the thermo neck and thermostat back in.

Or if you want to be a real cheap ***, locate one of the small coolant hoses up around the intake manifolds. Cut it, tee into it with hardware from lowe's, and use whatever adaptors necessary to install your sensor there. You may find it necessary to ground the tee/sensor if it is an electrical gauge. This is the cheapest and easiest method but also the most ghetto.