TommiM

iTrader: (19)

I love working on cars as well, but this aint nothing. Try diagnosing a German car.

If its easier, you can pm me and Ill give you my number so you can text me.

heel2toe

iTrader: (41)

Taking you up on that, thanks PM sent

Biggiesacks

It literally takes 2 minutes tops to check the connector to the temp sensor, and THEN you can cross it off the list. You cant just assume something is working properly without checking it. This is how troubleshooting works, you actually verify something is working properly before you cross it off as a potential problem. Bleeding air out of an engine is super simple Unless you are completely inept i dont see how you could have repeated this procedure so many times and still have this air pocket stopping your sensor from working. You have tried it so many times isnt it time to cross that off your list?

MyronGainz

iTrader: (6)

When this was happening to me it turned out to be a droplet of water in the actual connector of the temp sending unit. I removed it and blew it out, then replaced the sensor anyway because its like 15 years old now. Problem solved

heel2toe

iTrader: (41)

While I appreciate the feedback, what I am saying that if it were a sensor issue then how can you explain that it would start to go up and then drop?

I just undid the connection and it is in perfect shape. I just find it so hard to believe that the sensor just decided to s**t the bed at the same time that I did this whole procedure.

heel2toe

iTrader: (41)

So ive since acquired a pressure tester did that whole thing and it started to rise and then now the gauge is back on the bottom again. This doesnt make any sense...

I just pulled the thermostat and there is plenty of coolant in there. The sensor is submersed is coolant actually. One would think that if I turned the key to the 2nd position it would read some heat on the gauge.

TommiM

iTrader: (19)

its a relatively standard procedure BUT as with anything with cars, sometimes they can get finicky. I have seen a few times situations like this where the air pockets just don't want to bleed. S*&t happens.

MyronGainz

iTrader: (6)

Well, mine would go up normally when the car was warming up. But randomly during any kind of driving at operating temperature, the gauge would just go straight down to cold and stay pegged there lol

Biggiesacks

Electronics dont just have to fail outright. They can work then stop, then start working again. Contacts corrode and thermal breaks can cause all kinds of weird **** to happen. Take some sand paper, or scotchbright and clean the contacts. If you have it, apply some dielectric grease and plug it back together. If thats a no go you are going to have to bust out a multi-meter and do some electrical testing.

Biggiesacks

If you have access to an OBD2 scanner of some type, or better yet evoscan, you could pull the temp that the ECU is reading. If that looks right it would pretty much narrow it down to your gauge cluster. If the ECU isnt seeing any temperature then its going to be sensor/wiring harness related.

heel2toe

iTrader: (41)

So after repeated attempts at bleeding the system using various different techniques I still failed.

Sooooo, I ended up pulling off the thermostat and checking out that area. It was full of coolant and I saw both sensors submersed in coolant. Since it was still hot I went back over to the car put the key in and turned it two clicks to see if it would record the temp then and it was nogo.

I then pulled off the connector on the front sprayed MAF cleaner on it then blew it off with compressed air sanded the terminal put it back on. Checked the temp again ans it started to go up.

So after all of this it ended up being the sensor and my best guess as to how it got gunked up is that one of the coolant lines to the turbo sits right above it so when I pulled it off coolant must have gotten all over it and interrupted the connection.

Lessons learned here:

-Dont dismiss things until proven otherwise

-Not everything has to make sense

-Check the basics

Thanks everyone for your feedback. I guess I was a little stubborn to think that the sensor had crapped out on me. While that may have been true in this case it wasnt working properly as a result of something that I did so it all sort of comes together. I guess I got a little too hung up as I convinced myself that there is noway it could be the sensor when it reality it sorta was the sensor.

Biggiesacks

Glad you got it taken care of! Its all a good learning experience. Gluck and enjoy your evo.

Fast_Freddie

iTrader: (50)

Glad you listened to myself and Biggiesacks as it has obviously happened to both of us before... glad it is working, i know it was frustrating trying to figure out my issue as it happened out of the blue as well.

heel2toe

iTrader: (41)

Thanks guys. Yeah it was one of those things that didnt make sense as to why the sensor would get gunked up or go bad at that exact time.

After further investigation I've determined that when I removed one of the coolant lines going to the turbo I forget if it was the feed or the return but anyway I think it leaked right onto the sensor causing it to not get a good reading.

I didnt realize but there are actually two sensors that go into the thermostat housing. The one on the front is for the gauge and the one on the back is for the ecu. Had I known that before I would have pulled out my laptop and got a coolant temp reading to see if it was indeed an air bubble. I assumed there was only one sensor in there on the back as that is the one I removed to check originally and it seemed fine.

Anyway, the car is back together and seems to be fine now. Im glad I've got a drivable vehicle but a little bummed that I didnt get to do any tuning today.

Oh btw one of you mentioned using some dielectic grease on the connection. I actually meant to but then completely forgot. I guess if it aint broke dont fix it but I wonder if by using that itll help keep the connection good and sealed from her on out.

TommiM

iTrader: (19)

crazy stuff, well glad you got it all sorted out