996 coolant burning smell and brake problems

noah · 09-13-2012, 11:20 AM

Hi i have a 996 1999 with 40k miles. I have two problems with my Porsche and i thought i would post my problems before i take it into the dealership.

First, Every time i drive it i smell burning anti freeze yet my levels of anti freeze never reduces, or if it does, it reduces at a level in which i cannot detect. Also, I have no leaks under my car and i always check the fluid levels and it seems to be constant. Visual inspection of the hoses seem to be fine. No anti freeze is blowing out the exhaust either or from the coolant cap/ over flow hose.

Any ideas on what it could be and how i can check it?

My second problem is that the brake pedal is not releasing. I have to manually lift the pedal up with my foot. I thought it was the rear calipers but i replaced them and it slightly fixed the problem but now it takes 5 seconds for the brakes to release. I am thinking that its the master cylinder or the front brake calipers but i would hate to replace it if its not broken bc i just spent near a thousand replacing both rears.

Thanks much.

tonythetarga · 09-14-2012, 03:11 PM

Noah...even if your calipers were seized the pedal should still return. It probably is the maser cylinder. How long has it been since the brake fluid was flushed completely and replaced? Things might be gummed up in the m/c. I'd start by flushing the fluid with some good stuff. Start with the cheap solutions and work your way up. Replacing calipers is expensive and not likely the problem. Not replacing your fluid every 2 years will ruin the m/c and calipers after a while though. Remember your basic maintenance items and make sure they are taken care of. (like replacing oil and filter every 4-5k even if it is the Mobil 1 synthetic and costs a lot). Once a year regardless of whether you do less than 5k. Oil is cheap compared to a new motor.

If you are smelling coolant then it is getting out of the system somehow and dripping on the engine or exhaust. Might check the water pump housing or connections there.

FPB111 · 09-27-2012, 06:41 PM

Are you sure that the smell is antifreeze? These cars smell like burning rubber from the tire dust blowing back on the hot mufflers right behind them. Faster harder drives give stronger smell.

bornrich · 09-30-2012, 08:39 PM

As for the brake issue, I had a similar problem. Turned out to be a brake booster damaged by water. Hope this helps.

noah · 10-26-2012, 12:20 PM

The dealer suggested that it might be a leak in the coolant tank or water pump. But wouldn't I have a significant reduction in coolant levels after awhile? And I don't. It does smell like burning rubber as well and I always have a ton of brake dust on my rear bumper after a drive. But dang it really smells. I would like to think its a leak so I can address the smell

Hurdigurdiman · Hurdigurdiman's Garage

If you are not a DIY man now is the time to learn. Get on youtube and buy the tools you need. They are all free from the money you save by doing the jobs yourself. Flush out the braking system. Take it on the road and brake like hell. Flush the system out again. Do the same again See does that take care of the pedal.
If your coolant is not going down then you have nothing to worry about. Keep your eye on that. My guess is a hiss from a hose or radiator or a joint which is getting into you via the heater vents. Anything from the rear would be left alone in the dust. Theres a film on you tube on how to remove the front bumper to clean between the radiators and condensors. I did mine, I am 71 and its a dodle of a job. You can easily check things when you are in there.

Porsche 996 986 bumper removal - YouTube