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On my B6ME, when the car idles the temperature gauge works fine, upon acceleration, the gauge drops, the faster I go, the lower it drops. Is this a bad ECTS or possibly a notoriously bad ground?

Not to be a smart-a--, but this seems like your radiator doing its job.

Nope, in my gs if i gun it sometimes in neutral and sometimes in gear the needle spikes down on the temp gauge and back up.

The point is that the original post was not very descriptive and didn't include anything about it doing this in neutral aswell.

jkbreazeale wrote:On my B6ME, when the car idles the temperature gauge works fine, upon acceleration, the gauge drops, the faster I go, the lower it drops. Is this a bad ECTS or possibly a notoriously bad ground?

Simply, the faster you move, the more air that passed through the radiator. The more air that passes through, the more it can cool down the coolant. Reason why you need a rad fan, to move air when you're not physically moving.

93vtecklr wrote:Nope, in my gs if i gun it sometimes in neutral and sometimes in gear the needle spikes down on the temp gauge and back up.

The faster you rev, the more coolant the waterpump moves through the system. Eventually you working the motor creates more heat, so the temp goes back up.

I get what you're sayin, but then everybody here would have that happen. I'm talkin the temp needle shoots down and spikes up faster than the rpm gauge does. Could it be a faulty temp sensor getting a sudden reading of cooler fluid doing this?

Well, most people don't really pay attention to their temp guage, but also, the temp gauge going down isn't a bad thing, why would people complain about it?

There is the slight possibility of a bad sensor, but it's not common for them to fail, and that's a weird way for them to fail. If it's dropping a few points, than I say no, but if it wants to drop to 0, but it doesn't get a chance and comes back up, than it could be an intermitent bad connection.

If it does down and up predictably when you revving the car in neutral, it won't be electrical, it's too predicable for that.

True. True.

Wow...

I understand the air passing through the radiator and that the needle would drop like a mm or two, however when I gas the car, the needle drops to near the cold line, I live in North Carolina, not Canada so the air is not that damn cold. This is not normal and I know this, just not what it is... looking for guidance.

also, it only seems to happen when in gear, not in neutral.

We just replaced the thermostat on my grandmothers car, so you might try that. Though, her problem was a lot different, and was just that the temperature gauge fluctuated from being all the way at the bottom and cold, to in the middle and fine (and it did this at random times.. not RPM related or anything like that).

I would bet reasonable sums of money that this is an electrical problem. The signal being sent to the gauge by the sending unit is changing drastically in a very short period of time. That is not explained by normal cooling...or even erratic thermostatic function.

The difficulty is that a broken wire can be very difficult to nail down. There should be a single wire from the temp sender to the temp gauge. If you can try to test the continuity of that wire. Try it while wiggling stuff around to make sure that continuity isn't intermittent. From there I would change the sender.