Lets talk engine temp and other gauges!

so before I go FI im trying to get a handle on all the gauges and such...im going with wideband, boost, oil pressure, and trans temp (also volts for system).

We already have an oe engine coolant temp sensor so im wondering, just how accurate is it???
I have read elsewhere about adding a ground wire instead of letting it ground via threads which makes sense...
if it is inaccurate has anyone tried getting an aftermarket gauge and using the sendor from it and wiring it up to the oe gauge?

don't turn this into a "that's a shit setup because its not mine and only I am right" thread please ^.^ if you have an opinion that's great but back it up with some sort of experience or data cuz blowing smoke only clouds up everyones view :p

I have no idea how accurate the sensor is. I also dont know how you would verify it other then taking
the temp of the coolant which would be hard to do. Is it possible? I dont know if theres a specialists tool
for that. If I had to I would take my laser thermometer and aim it to something that transfer heat easily
like the coolant hose. Would it be accurate,,,, might be close.

Also how would you compare that number to your cluster gauage, correct me if wrong the cluster gauge
doesnt have numbers. I dont know if an aftermarket sender would be compatible with the stock ecu, it might
even do more harm then good if it cant read it.

If I was worried it wasnt accurate I just replace it with new oem sensor. If you want to add more gauges like temp
and psi then add them with right adapters. They sell special adapters for coolant temps that go inline with your
coolant hose.

For your w/b the instructions will tell you how far down stream to put the bung. Volts is nice to have but not critical.
I just installed a volt gauge myself, I dont need it but it beats pulling out my voltmeter.

The OEM sensor works fine. If you overheat, it pegs, that's all you really need to worry about.

I will agree that the OEM sensor is plenty accurate, I've been able to catch the temp creeping up before anything bad has happened. Not sure what adding the supercharger will do to underhood temps as I don't think it will make as much additional heat as a turbo. I know it takes a lot to make the things overheat if the cooling system is maintained and healthy.

I've already got the AFR and made a custom-ish volt meter. Boost gauge is actually going to be a cooling mist methanol injection controller/boost combo thing.

xd_01 you are correct, there are no numbers on the temp gauge but it wouldn't be that hard to figure out what it is then just guess from there ya know :p


thanks for the info, I've seen your autocross vid you posted a while ago and if you can consistently run like that without doing anything I'm not worried at all! I almost never get on in and when I do it's pretty quick and well after she's warmed up. I was just curious how reliable it would be since, like you said, not sure what's going to happen when I slap that thing under there XD

and I guess with the meth kit I could always just crank the levels up if it seems to be running hotter than I want XD

[IMG]http://i1157.photobucket.com/albums/...erwithPods.jpg[/IMG]

and here's a pic of the pods I just fab'ed in for the next 2 gauges (plus the triple A-pillar)

and once I get the gauges to go in the holes I might cut them back a little so they don't stick out so far XD

I'd be most concerned with AFR's, I'll be running dual LC-2's in place of the factory sensors. If you want widebands I can get them for dealer cost here in town.

Back to coolant temp, I just don't see the need for numbers, the easy thing would be to index the factory gauge, which I can do it would just take some time. Without a range chart handy the sensor should read about 35000 ohms at -40* F down to 500 ish ohms at 300* F so there is quite a range for accuracy in the temperature the computer reads. Honestly all I'd do is add a mark at mid gauge and make sure to let it idle to cool down if it got much above that.

agreed, I was thinking about fuel psi also/instead but any fucky fuel stuff will show up in the AFR anyway. since the ECT gauge sits pretty much dead center horizontal now any changes are gonna be pretty easy to see so just stick with it =] just wanted to make sure it wasn't gonna react like a narrowband or something where its cold/good/overheat ya know =]