leftlane

Hi all - took my car out for a drive last night - hadn't been driven much in the last month or so. All was fine until the way home, when I turned onto a residential street and heard a very strange noise from the driver's rear - almost sounded like a flat tire, but was burbling at low speed like an exhaust issue. No loss of power, no loss of boost, no lights - noise would come and go and was not present at normal speeds, just occasionally at low speeds (less than 15 mph). I couldn't get it to reliably reproduce before shutting it down for the night.

This morning there is an orange fluid on the ground, and I can barely see under the car to find where the drip is coming from. See pics attached - the fluid is slightly oily, not a huge amount but obviously has been dripping overnight. I have not started the car at all today since this kind of stuff freaks me out. Any ideas as to the culprit - what fluid and where the leak might originate? I wonder if the noise was from the fluid hitting the hot exhaust and burbling.

I figure it's coolant coming from somewhere underneath the tank - can't tell if the tank has a split, a hose has failed, or if maybe a fitting is giving out.

Sorry for the pics - the car is in a small one car garage and I don't want to start it if it could worsen the issue.

2004 TT cab - 6 speed, 63k miles.

Rvca3112

Any liquid against a hot exhaust wouldn't cause a burbling noise, just slight hissing noise. Also you would see some sort of steam coming up from the rear deck lid vents if that was happening. Coolant is pink, oil is tan/black. I think that may be power steering fluid or coolant.

leftlane

Thanks - wouldn't power steering leaks be towards the front where the reservoir is? Seems like it's pretty well located under the coolant tank if I have my tanks correct.

I didn't have any overheating last night and obviously didn't see a total loss of fluids, but the coolant tank is around the minimum mark today.

996tt6156R

Looks like your water pump is going.

Macster

Did you check the power steering and brake fluid reservior fluid levels? Check the windshield washer fluid tank too.

If I had to guess I'd say that was anti-freeze. The noise event may be unrelated but it could have been from the water pump.

Regardless it is going to be pretty difficult for you to ID the leak source with the car on the ground. My advice would be to get the car to a shop and in the air and so a thorough search can be made for the leak source.

Should be pretty easy to spot once the car is on the lift and the tech and you are under the car with bright flashlights.

How you want to get the car to a shop is up to you. I'm reluctant to drive a car when I suspect a water pump or even something with the accessory drive being wrong.

Without knowing the source of leak and what if anything the noise might mean I'd have the car flat bedded to a shop rather than risk driving it.

996tt6156R

Power steering is not pink nor is brake fluid.

Sounds like your water pump is going. That's the first signs.

Carlo_Carrera

I would also check the coolant overflow tank.

"02996ttx50

^ was gonna say.

to me, that appears to me original ( older) coolant. leaking from the ( commonly cracked and/or yellowed with age ) expansion tank. if so, then it could well be the original fill and an old tank that has finally failed. also from the pic, it doesn't appear viscous enough to be pentosin.

iirc? the older original coolant wasn't pinkish ( like g12/13 ) but was an orange ish color. also check for whitish residue around the left motor mount directly under the exp tank. if you see any? than you have probably had a slow hairline crack in the expansion tank, which is not slow any more. many of us have.

last thought.. pentosin ch202/11s is darker purple/maroon(?) but thats not generally where you'd see a puddle, if say, your accumulator had failed. it'd be closer to the center of the chassis rear.

I'm betting that is in fact, coolant, whether "old" or not. good call also on the failing WP possibility. that'd leak coolant for sure!

best i got.. GL w it.

leftlane

Thanks everyone - it appears that it is coolant, and my expansion tank is right at the minimum level right now. It isn't leaking very fast at all. I am concerned about the noise though - would a failing water pump make some kind of noise? It was almost like a rough exhaust brap at very low speeds - I at first thought I got something stuck under my car or on my tire. It went away with any revs at all.

I'll most likely flatbed it to my local indy next week. I don't want to make anything worse by having WP fragments running through the system.

Any ideas on costs to replace the expansion tank and/or the water pump?

"02996ttx50

flatbed it for sure as mac/others have suggested. a slow leak of the tank can be endured for awhile by watching the levels. topping off w distilled or even 50/50 g13..

but "puddles" aren't that forgiving and are obviously a sign of a more "catastrophic" failure. i wouldn't chance it. cant help on costs but hope its just the tank, as that would be the least expensive repair. GL.

Macster

Noises are hard to diagnose. If the tank is leaking the noise could have arisen from coolant leaking onto some of the accessory drive hardware.

It could have been something got momentarily caught in the belt/accessory drive system. Don't laugh.

Last Monday drove my Boxster 30 highway miles to the office. A few blocks short stopped to pick up some breakfast. The car sat just maybe 5 minutes. Upon restart there was a low pitched intermittent but regulator growling noise. The noise was slower than engine idling speed and slow enough that it really had me thinking a bad serpentine drive belt. But no warning lights and everything was otherwise ok.

I drove on to work and parked the car. An hour and a half later I was back at the car. I started the engine and the noise was still present. I decided to flat bed the car to the dealer (30 miles away) vs risk driving it.

After a 30 mile ride on the back of the tow truck and back on the ground with the SA and senior tech there I started the engine. Dead quiet other than the normal engine noise a healthy engine makes.

Since the car was due for a 5K mile oil/filter service I left the car there. Tech did the oil change and road tested the car. Still no noise.

We talked and left the car there another day during which time he checked the belt which was fine. No signs of rubbing, of coming apart.

The accessory drive pulleys showed no signs of rubbing by the belt and there was no bearing/shaft play. Even the water pump which has 138K miles on was fine. Not even any leak sign.

So I picked up the car one morning right when the shop opened and drove the car 30 minutes and got it fully up to temperature. Even stopped to fill the gas tank to duplicate the 5 minutes the car sat while I was getting breakfast back on Monday.

Even after the 30 minutes still no signs of the noise I heard Monday.

Both the SA and tech told me likely something blew into the accessory drive system. The SA and tech said they see maybe 5 to 6 cars a year in for noise suspected to be from the accessory drive area that proves to be non-reproduceable.

Have had the car back now this entire weekend and have driven it some with still no noise.

Just my way, my long-winded way, of highlighting how a noise may not mean anything at all.

But still to be *safe* I'd not risk a drive of the car. Any runnning the engine gets should be in the presence of a qualified tech with the goal of him making a quick and accurate diagnosis as to what is going on with the noise, if anything.

Besides the leak is real enough. Get that addressed. At the same time a check can be made of the accessory drive system. If it was truly the source of the noise the cause should be easy to spot.

Well, unless the source of the noise was something that momentarily got caught then got loose again. But if there is a real problem the tech will spot it.

Chessie

I had very similar symptoms when my water pump went bad. First signs of the problem was a gurgling sound I could only hear at idle. Thought is was my imagination at first, but the longer I drove, the more clear it became. I considered there was a problem with my coolant system, but noticed my temp gauge was holding steady so I kept going. Eventually made it to where I needed to be, and once the car was stopped I lost a whole lot of coolant. Took it to the shop only to find that the water pump, which was my suspicion, had torn itself apart.

Good luck with the diagnosis and eventual repair -

-c

leftlane

You guys were dead on - shop came and picked up my car today and the bearing in the water pump is failing. They are replacing the water pump and also the belt since they have to remove it anyway - don't need plugs or coils or anything else that would save me some money on labor. They are going to check the T stat while they are there but not anticipating needing a new one - also checking hoses.

Thanks everyone for the help!

"02996ttx50

good news it was a simple and easy fix. back on the road..just in time for spring!