Overheating, need advice!

[jdesigns]

I am finding the the Bentley CD isn't great for determining locations of parts. Can someone point me to the Coolant Temp sensor in ths pic? I think I found it, and it's green, but I am not certain if it is the Coolant temp Sensor.

I started having overheating problems this afternoon. The Temp idiot light came on and flashed red. I pulled over as soon as I could. The fans were going, and the coolant reservoir level was higher then the lines on the side of it. As I was limping it home, the Red flashing temp light came on again, this time joined by a flashing red oil pressure light. I checked oil level, and added enough to bring it up to full. The oil light went out, but the Temp light kept flashing and beeping at me.

I am thinking I finally had my waterpump fail, but I want to make sure that the Temp sensor isn't the culprit at this point.

IS this the general locatin of the Temp sensor? If not, you can use my pic to point it out. Forgive the dirtiness, it hasn't been detailed yet this year!

[from Margaritaville...]

Justin,

Gotta go fire up the BBQ, but I've got a minute. I'm looking at my printed version of the Bentley.

On page 19-16, it shows a 4-pin harness that plugs onto the coolant temp sensor ( or a 2-pin for the AEG engine with A/C only).

It also warns to release the cooling system pressure before removing it.

[jdesigns]

Thanks Alan!

I'll have to go look again, but I don't think the thing I was looking at had 4 wires. I do remember two contacts, or sockets, but not 4 wires. Hmmmm.

I'm thinking the stealership is going to get it on monday.

[paultakeda]

Get the breather hose (the ribbed hose that goes to the airbox, your question makr is right on it) out of the way and you'll spot it underneath.

At the angle of you pic, it's just a litte above the question mark underneath that hose. It sits upright and you'll spot it because it's just about the only thing there with an electronic connector.

Make sure you do this when the car is cold.

[jdesigns]

Thank you Paul! I attached a pic to verify that I am looking at the right thing, correct?

I got to thinking, after opening the hood, there seemed to be a irregular amount of heat coming from the engine. This tells me that the engine is quite hot, which means to me that the sensor is probably fine as it let me know the engine was hot.

If my thoughts are on track and the sensor is working, then the next step should be the thermostat, right? Can someone point it out to me? I hate being this "dumb" when it comes to my own car. (Give me a schematic and an airplane and I could rewire the whole thing, no problem. But ask me to find a manifold on my own car? I can't even guess.)

[GTRAFF]

The thermostat is just beside the rear of the alternator. You will see the hose coming out of the cover for the thermostat. It looks possible to get it out without removing the alternator, but I have not changed one so I can't say for sure if you have to remove the alternator or not. Might be easier to change with the alternator out of the way.

[jdesigns]

Thank you! I'm gonna see if I can find it and change it out.

[oneighturbo]

you got the Temp sensor correct. its an easy fix but as paul said keep it cold.

the thermostat is a bitch. its next to the alternator and under the manifold.

it sounds like you may need your timing belt done. these are the exact symptoms i had.

how many miles?

[jdesigns]

Thanks for the reply Corey!

Mileage is sitting at 48170 at this very moment. From what I have read here on the Org, there isn't any way to tell if the Waterpump went bad, other than overheating, right?

I'm gonna have the wife call the dealer tomorrow and see if they can squeeze it in to take a look. If it is the waterpump, that should be covered under warranty.

I'll have them do the timing belt if the need to tear into it.


(Why isn't there anyone with VAG-COM near? I guess I should buy one, eh?)

[mezonesxbox]

I think its your water pump, CHANGE IT!! You'll save a lot of money. I ignored the problem and kept adding coolant and drove for a week and blew my head gaskets $1800 to fix!!

[jdesigns]

Originally Posted by Porkchop

.....3. Normally you could minimize coolant loss by pulling the old thermostat and putting the new one in quickly - but in your case, you need to examine the impeller so expect to lose a ton of G12.

Enjoy!

How much would a ton be? I wonder what size container I'll need to use to catch all the G12, instead of letting it run across the parking lot.

[rcy]

Originally Posted by Porkchop

If you're going to change the thermostat next, you should be able to see the water pump impeller once you remove the thermostat (shine a flashlight in the hole with the thermostat removed). Then you'll know for sure.

Incidentally, my understanding is the thermostat housing is identical on your engine to my 2.0L - so let me give you the benefit of my removing it twice in the past week:

1. Make sure you use a new o-ring - reusing the old one will almost guarantee it will leak (more like seep once the engine cools down, in my case)
2. Even though the bolts will accept either a 10mm wrench/socket or a 5mm allen wrench/key, there is not much point trying the allen key on the bottom bolt. I found a combination of a 1/4" socket set with 10mm socket and no extension and a 10mm open end wrench worked best on that bottom bolt. The top bolt is easily accesible.
3. Normally you could minimize coolant loss by pulling the old thermostat and putting the new one in quickly - but in your case, you need to examine the impeller so expect to lose a ton of G12.

Enjoy!

You can also stick you finger in the thermostat opening (after you remove the thermostat) and feel the impeller. You will be able to tell if it's broken etc. by doing this. For the bottom thermostat housing bolt, I used an extension with a univeral joint thingy (you know the wobbly adapter thing).

[jdesigns]

Thanks Justin!

I just got back from taking it to the dealer. It's under warranty, so I might as well make use of it while I can. They are going to diagnose the problem and call me this afternoon.

I may not know much about the workings of a car, but something tells me that if the water pump isn't circulating the coolant around the system, then I probably am not going to have coolant moving through the heater core, thus a failure of the water pump would explain the lack of heat coming out of the vents on the way to the dealer. (WOW! That was a run-on sentence if I ever saw one! My english teacher should be proud!)

Am I correct in this assumption?

[oneighturbo]

Originally Posted by jdesigns

I just got back from taking it to the dealer. It's under warranty, so I might as well make use of it while I can. They are going to diagnose the problem and call me this afternoon.

let us know. if you are under warranty, use it. i wasn't.

these things have a mind of their own. mine went at 40k.

im not sure if a VAG-COM could have helped but it is a def buy!!!!

[jdesigns]

The dealer just called and said it was a ECT, Engine Coolant Temp sensor. I'm not thinking it's right, but that is what codes were thrown. I'll put it through it's paces tonight and find out.

Thanks everyone!

[The Cheat]

Bad temp sensor would be a constant blue light. You'll be back at the dealer soon enough as crappy as that sounds.

[jdesigns]

I certainly hope you are wrong Justin!

[oneighturbo]

j. i know you dont need this but if anyone else reads this and needs a kit...

http://forums.vwvortex.com/zerothread?id=2618678

[jdesigns]

Well, I just got home from the dealer......without the TS. We took it down the highway after picking it up, and sure enough the red temp light started flashing again.

So we took it back and they were "Surprised" by it coming back. They did say it popped a P0117 code, which I haven't looked to see what that is yet. They R&R'd the ECT sensor and "road checked" it. I looked at the mileage when I dropped it off, and when I got in it this afternoon, there wasn't even a full mile on it. I don't know how they got it hot enough to make sure that it wasn't overheating again. I had to drive it amost 6 miles to get it to come on.

Just proves what most of us believe about MOST dealership mechanics.....they are freakin' idiots!

If it does come up that it is a water pump that came apart, I think I might have a word with the GM about the "Service" or lack thereof.

[jdesigns]

The dealership just called, and said they replaced the Thermostat, and the water pump impeller was shattered. They didn't even call me to let me know that they were replacing the water pump. I'm a bit mad at that. I was going to have them do a timing belt at the same time, even though she said the timing belt is good until 105k. They probably did it on purpose just to get more money out of me.