Pimpo

I just installed a Mishimoto oil cooler, with the thermostatic plate and 200* switch. The sandwich plate comes with a bung for a sensor, so I added a VDO temp sensor, connected to an Innovate MTX gauge (pressure and temperature)

Everything seems to work fine, but I'm reading high temps when the engine warms up. The gauge progressively increases as the engine warms, as it should, but it goes up to 260F when the car is parked (giving it some revs to warm things up quickly). Water temperature is fine at 190.

When driving the car, the temp goes up to 250 or so, if cruising around, then up to 270 if I start pushing it. All it takes is 30 seconds of pushing the car to reach that temperature.

I have to think this is a sensor/gauge issue as the water temp does not go higher then 192F. I added an extra wire to the sensor to make sure it grounds properly and I checked the sensor with a multimeter to make sure it closes the loop. I also shielded the sensor with high-temp aluminum tape since it is so close to the headers.

The only things I can think of is:

1) Sender is too close to the header and it is still soaking up heat, even though I tried shielding it
2) The sender and the gauge do not work well together...assuming here that they all work the same?
3) The gauge itself is not grounded properly...but the pressure sensor works great and the temperature part increases/decreases gradually as it should...it just goes way higher than I thought it would

Is anyone running a similar set-up and getting proper readings? Sorry for the crappy pictures

spdracerut

My guess is the calibration of the Innovate gauge does not match the output of the VDO sensor. Basically, I'm guessing the voltage vs. temperature curve of the VDO sensor does not match what the Innovate gauge is use to reading. So, for example, the VDO sensor is outputting 3.5V for an oil temp of 200F (where your oil thermostat is set to). In the calibration table for the Innovate, 3.5V = 250F. Something like that. I think it's best to get a hold of tech support from Innovate.

flanders

Yes there are lots of different ohm ranges on the various types of VDO temp sensors.
If you didn't get yours with the MTX gauge you probably have the wrong type, if you are lucky maybe the gauge can be re-calibrated.

Pimpo

Ah that makes sense, so you don't think the heat from the manifold should affect it ?

Jin_SK

If you want to be sure, I'd check the voltage you're getting directly from the sensor and comparing with the table you got for it. If it's still showing abnormally hot then you'll need to shield it better or find a different location.

Pimpo

OK I tested with another VDO sensor I had, the innovate one, a bowl of hot water and a multimeter. The innovate reads ~2.7x the resistance of VDO.

I contacted Innovate, I don't think The MTX gauge can be calibrated so I hope they have a firmware that can address this, otherwise I will just set the lights according to the converted value.... I don't want to disassemble anything unless I really really have to!

Thanks for pointing me in the right direction, hope this helps others with the same issue.

boyguan

In the end for me,i break sensors there. I have gone through 2 oil pressure and 1 oil temp. They say the vibration there and the heat from the manifold doesnt help and to move it else where if possible.

spdracerut

Maybe and an inline resistor to your VDO to get it to match the innovate?

Pimpo

Yep I thought about that too but I can't find the detailed specs for the Innovate sensor, hopefully I get a reply from them.

tehlonz

Why don't you just use this?

http://www.innovatemotorsports.com/x...4&cat=0&page=1