Dad's V-Dub is having odd overheating issues

Ok, try and stick with me.

My dad called and told me his car is having water temp issues (it's an 04 Golf, 1.8 NA). When he's on the freeway going 60 mph, the water temp sits about 200*, but as soon as he tries to go above 60 he can actually watch the water temp gauge start climbing; it gets to 230 within 10-20 seconds. So, he slows back down to 60 and it returns to ~ 200*.

So, he replaced the thermostat thinking it was stuck closed or something. Didn't help, same thing. Now here's the kicker that really confuses me... say at 60 mph in 5th gear the car is at 3,000 rpm and at 70 it's at 4,000 rpm, which is when the temps start rising. I suggested that if he is on a city street, leave the car in a lower gear and rev it out to see what happens. So, he leaves it in 3rd doing 4,500 rpms for a good minute and the water temps stays at 190*! That contradicts everything I can think of. At a higher rpm, and slower speed, it doesn't overheat. The water pump is belt driven at higher rpms and the radiator is getting less air, but it stays cooler?! Why is it overheating in 5th gear at 4,000 but not 3rd at 4,500?

I mentioned to pop the radiator cap while the car is idling to see if any air bubbles are coming through,which would point to a blown head-gasket, but it still doesn't make sense to me.

I am at a loss...

See, the problem with the car is that it's a Volkswagen. Tell him to get a Honda or Toyota, or if he wants to stay German to get a BMW or egads! a Porsche, and it will all sort out nicely.

Seriously though, if I were you I would post on a VW forum. Maybe it's a common thing.

there's some equation involving the combustion temp, based on the amount of gas/oxygen burned, per rpm relative to the speed of the car, due to the drag. low speed/high rpm still burns a lot less gas than high speed/low rpm.

i only vaguely remember an argument about this on c&d years ago, but i bet his water pump is fucked.

Is he noticing anything in the overflow tank?

Maybe it is just a bad temp sender?

Talon wrote:Why is it overheating in 5th gear at 4,000 but not 3rd at 4,500?

that makes sense, in 5th gear there is a heavier load on the engine to keep the car moving, so more heat.

I would guess it to be a water temp sender possibly. Or does he do lots of "muddin" so his radiator is full of mud and dead frogs? Or all the fins fell off the radiator?

^^ yeah, what they said ^^

I thought about the sensor, but I would have assumed that the mechanic had checked that before suggesting the thermo to him. Where are those located, anyway?

I thought maybe the fan wasn't kicking on at higher speeds, though I don't see why speed would even be an issue whether the fan kicks on or not.

Only thing he said was the radiator cap was really easy to turn and take off, and probably wasn't sealing the best.

Fffffffffffffuck where's CK when I need him?

well if you think the cap is suspect buy a new one, because if its not pressurizing right it won't run at the right temp either.

Talon wrote:I thought about the sensor, but I would have assumed that the mechanic had checked that before suggesting the thermo to him. Where are those located, anyway?

you trust a mechanic???

they are located in several spots, some cars may have more then one. Usually on 4cyl's they run coolant thru them and typically thats where you may find a Water temp sensor. (usually you can test them to see if they work)

I'd say make sure there isn't anything stuck to the front of the radiator like a plastic bag. Also, 4-cyl VWs used to be notorious for getting air pockets in the coolant system so maybe make sure that while the engine is running after its at operating temp the hoses feel firm.

check out SBF dropping some science on deez niggas

Yeah 4 years of tech school helped dat shit

When you find out what it was, be sure to let us know

Yeah really, we get tired of being left hanging in the wind.

I will. He was about to take the car on a 1700 trip. Obviously the car wasn't up for it so he had to take his truck. When he gets back I will find out what it was...

Does the car smell like its running hot? You know that smell. It smells bitter and putrid, from the coolant and engine oil boiling away.

Is the fan kicking on? Ok when you start it have the hood up and crank the AC on max, the relay should kick the fan on in about 15 seconds, if it doesn't kick the fan on, the relay is bad. Thats they way it works on alot american cars. But may be the same with vw. If relay is good then the culprit would more than likely be the the temp sending unit that sends the signal to the ecu , which in turn sends the signal through a fuse then the relay. Not the temp sending unit for the guage. Now that is basics. I hope it helps with vw.

Oh and if you are not sure about the fan motor/motors, unplug them and jump them to make sure they work.

the fan doesn't HAVE to kick on when you're at speed. guess why.

*bites lip* ...........because it's union?

hahaha! ba-ZING!

"Made in Germany. You know Germans always make good stuff."

I knew that Sham-Wow guy was full of shit.

big_jesus wrote:the fan doesn't HAVE to kick on when you're at speed. guess why.

I didn't know if they were coming at all. I was trying to deduce things over the net, which is not always easy without looking at it and testing.

Talon wrote:"Made in Germany. You know Germans always make good stuff."

I knew that Sham-Wow guy was full of shit.

got his ass kicked for it, too

Aristotle wrote:

Talon wrote:"Made in Germany. You know Germans always make good stuff."

I knew that Sham-Wow guy was full of shit.

got his ass kicked for it, too

]

"You're going to love my nuts"

Aristotle wrote:

Talon wrote:"Made in Germany. You know Germans always make good stuff."

I knew that Sham-Wow guy was full of shit.

got his ass kicked for it, too

His parents certainly weren't German.

Well what did it turn out to be?

water pump got slap chopped is my guess.

Bluntman wrote:Well what did it turn out to be?

Good question... I will ask next time I talk to him.

Talon wrote:

Bluntman wrote:Well what did it turn out to be?

Good question... I will ask next time I talk to him.

oh for fuck's sake, talon

GET ON THE STICK!

SBF wrote:

Talon wrote:

Bluntman wrote:Well what did it turn out to be?

Good question... I will ask next time I talk to him.

srsly

Bluntman wrote:

big_jesus wrote:the fan doesn't HAVE to kick on when you're at speed. guess why.

I didn't know if they were coming at all. I was trying to deduce things over the net, which is not always easy without looking at it and testing.

sure. also, talon's post is about the car overheating when it's moving.
i mean... that's the point. that's when the problem happens. so...

A girl at work bought a new Golf last week. Already had two electrical gremlins...

Swerve wrote:A girl at work bought a new Golf last week. Already had two electrical gremlins...

lulz, I haven't talked to him in a while.

I called him for you assholes... he said it was the water pump. Replaced that and the timing belt. Runs good now.

Benfolio wrote:

That video is awesome