Update: Engine coolant Still Low

2003 C4S with 33K miles. Bought it few weeks ago. Was told it was good-to-go. Engine coolant level looks quite low. I'm not used to 996 engine coolant, which I assumed would be pink, and this is closer to bright yellow. Pics below. Normal, or am I ? Update : Refilled and low again...has to be leaking. See below for new post.

It does look low. Porsche has two kinds. i think the newer coolant is pink; the older version was yellow. You can mix the two.

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Mine came with yellow, Porsche only sells pink. I mix the two. Check your cap part number. It should end with "03" or higher. I switched mine out and had success.

In the old 944 I had to bleed the system if I wanted to go pink. From what I'm reading here, no need to bleed; just mix by topping off with factory pink; correct? Last thing I want is gel, so pardon the repeated question.

By the way, here's why I get nervous: !

Both are compatible. http://www.renntech.org/forums/index...water-top-off/

I would buy distilled water from CVS or Walgreens for this. No reason to buy coolant to top off.

I topped mine off with some Water Wetter

Bought Porsche pink plus distilled water; no reason not to do it right. Agree that for the little that's needed I could use distilled water, but honestly, it's a good car. I can spend the $40 on the coolant.

u better find out where the coolant went, check the bottom of your tank, make sure u don't have any hairline leaks.

Was refilled two days ago to between min and max, and now it's right back under min, as if it was never filled. Clearly leaking, but where? No moisture I can see. Under a warranty, may end up at the <dun dun dun> dealer's shop....

Have you checked your oil dip stick and see if there's any goo? Had the tank been replaced right before you bought it? If it was, it's possible the bleeding was not completed and you're just seeing the air trapped inside being bled out. You can pulll up the bleeding valve (the black valve with a pull pin that sits on the top of the tank) and drive it for a few days to bleed the rest of the air. Do you have a cap that ends with .04, the latest? A very commonly failed part. Maybe repeat the filling for one more time and recheck. Next stop is to the shop for sure if coolant keeps disappearing.

check the bottom of your tank, looking for white powder, and the sweet coolant smell. u tank looks very white, was it replaced recently?

No goo; just oil. Not that I know, nor have any record of. No; 996.106.447.01 is the cap part number. None; none noticed. No dripping coolant, no puddles on the floor. Did exactly this; I'm realizing that the tank itself and the overflow (reservoir) tank sit right next to each other. Unsure if last time I actually was patient enough to let the tank itself refill, or whether I let the reservoir refill and walked away (although that would be very odd and unlikely). This time I added another 16 oz. or so coolant:water and waited. Refilled to above Min line again. If still low in a few days, it's off to the shop. Thanks for the help.

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Unless you drove alot of miles in that 2 days since the refill hard to believe the cap could be at fault, though a new/updated cap is recommended just on general principles. To state the obvious, there is a serious coolant leak. You have verified the engine oil has no coolant in it, so the leak is from the cooling system to the outside. My first guess would be the coolant reservior tank. But another possible source is one of the radiators though the hole or leak is up high not low. This could be a hole in the radiator or a hose or a hose fitting/connection. Yet another source of a coolant leak is the heater core. Have you pulled the bumper cover and swung the A/C condensors out of the way and checked the radiators as best you can for leaks? Be sure the A/C is off. Top up the cooling system and get the engine nice and hot by running the engine at idle until warm then raise the engine speed to say 2K rpms and hold it there for 30 seconds then let the engine idle for 30 seconds. Repeat. You want to get the cooling system hot enough the radiator fans come on (which IIRC is 212F. They shut off at 205F.) Have the fans come on once, then shut off. When they come on again shut off the engine and check all around for any coolant leak. Use your nose. Use your eyes. Be careful! I did this to check if a radiator fan was working and the coolant tank let go with a gush of hot coolant. Had I been under the car instead of standing a few feet away looking at trail of coolant I would have gotten scalded. Ideally you want to have the car on a lift so you can look under the car from the water pump forward, looking at all teh water hoses, fittings/connections. But you have to be aware that with the cooling system hot and under pressure what was leaking a bit of coolant over some days could decide to let it all out in one big gush of hot coolant. Sincerely, Macster.

Fantastic help; a few thoughts: Thanks; it went about 100 miles or so, but still. Upgraded cap is the -04, or more recent? Not yet; I'm going to play the noob and admit that the car is new to me, and that any minor work even makes me slightly nervous, although I did minor repairs to the 944 (window motor, etc). With a diagram and some help I'm sure I can search for how to remove successfully. I assume this is with the bumper cover removed, and AC condensers out of the way? I don't have a lift, so I'll have to do the best that I can. I haven't seen dripping liquid or puddles in the garage, but I will check again and update. Thanks again.

my bet is that you are loosing coolant from the overflow... the tube drains down the sides and doesnt touch anything (like your ac drain). While you drive it overflows (expands) and when stopped, the coolant resettles below where you last filled it. Im thinking that this level is the coolants normal level.... The min/max window is very small on the tank.... The 996 has cooling issues and this is where your coolant level wants to sit.... its not that big of a deal if it sits at this level all the time. I suggest you drive it more and see if the level continues to drop. If you dont... then this level is normal for your car. But, If you continue to loose even more fluid, then for sure you have a problem. Also, when filling makes sure you burp the line by driving the car for a day or so with the pressure valve open.... after the drive, just close the valve to seal the line. This will purge most of the air out of the line.

Thanks. I did not "burp" the line when last filled, but with this filling today, I will open the valve x 1 day and do so. I should mention that the car is new to me (800 miles ago) and was PPI'd on purchase last month; completely "clean." Unsure whether this would have been seen, if it was a major leak, if they did not drive it.

Peter, The "burping" mentioned above will require a few heating cycles - up to normal engine running temps and then cooling down to ambient with the pressure bleed valve open. Some people (me included) drive for a few days with the valve open to rid the system of any trapped air. Top up the coolant every day untill the system stabilises. When I replaced my coolant the first time, I couldn't understand why I was having to top up every other day - I then found out that the pressure bleed valve HAS to be open to expel all the trapped air....

Thanks. So if I'm understanding right, there's no harm in keeping the valve open for a few days, when the car is either in use or not, in garage? Drive car, let car cool, refill, repeat x few days until stable, all the while with the valve open, correct? It sounds like the options are (1) this isn't a disaster, it's normal and it may take a few days; or (2) I'm hosed and there's a leak somewhere yet undiagnosed. Either way, a few daily drives with valve open and refilled as needed should do the trick and clue me in.

That is correct. If you do have air in the system, it will take ages to clear without the valve being open and it looks just like you are losing coolant but you are actually only topping up. Of course, if you do have a leak, then you will continue to have to add coolant and it's imperative for you to see where it's disapearing to..... As a matter of interest, I keep my coolant level approx one inch below the bottle "max" mark, and indicate it with a pencil or crayon. Then I can see immediately if the level changes. Make sure you fill to the mark with a cold engine and check it with a cold engine, as when it heats up the coolant is above the bottle's "max" line....

driving with the valve open will not harm the engine at all.... from what I understand, the cup cars run like this during races without issues.

I just had the front drivers side radiator replaced because i cracked it hitting road debree, it took 3 days to get the air pockets out, i had to keep going back to the place to have them top it off..maybe as simple as that! and finally now the coolant smell is going away ..they had dumped some and it burned off and smelled nasty ..these cars are notorious for the time it takes for the air pockets to go away

Took a look today cool and was still right above Min, where I left it. Did exactly what Macster recommended; ran until warm, then 2K x 30 secs, then idle x 30 secs, repeat. Fans went on/off. Shut car off and looked for leak. Not a drop. Checked the reservoir (by sight only!) when hot; was just under Max. Left alone for a few hours, cooled down and it's back to where I left it cool, right above Min. Will open air valve tomorrow and this week while driving (keep it open for 2-3 days), then repeat process and see how I do. Let's hope that it's a non-issue, and I can't thank ya'll enough, since it was on its way to the shop before I posted. Might still end up there, but heck, at least I'm more informed.

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I'm a little uncomfortable running the car with the bleeder valve open. The only thing that keeps the coolant from boiling is pressure. If the valve is open and if this open valve allows pressure to escape the engine could see localized overheating as the hotter spots in the engine flash the coolant to steam and this steam blocks further coolant flow. This is a sneaky kind of problem cause the coolant temp may not, almost certainly will not, go up any big amount since the coolant is flowing by the hottest spots and removing heat. I've never had to bleed my cars' coolant systems. In all cases the cooling system was refilled using a vacuum/refill system that ensured no pockets of air. And no driving around with the valve on the coolant tank open. Sincerely, Macster.

Macster, what makes you nervous? I'm interested in learning, and multiple opinions are the only way to do so. Do others concur? I'm down again today, meanwhile....

When the engine is at operating temp the bleeder is up hard against the top of the bleeder housing. When the engine cools the bleeder is down unless the bail is in the upright position holding it up (open?). So driving with the bail up it seems that the engine would not see anything different. It looks like the bail causes a vacuum break that lets the hot air pockets pull water into the maze displacing the air as the system cools?? That is why multiple heat cycles seem to purge the system better then one long drive.

Wierd....I am having the same problem! Just bought a 2002 C4S with 30K miles...was having an issue with mildly fluctuating oil pressure gauge, and while playing with the connections, noticed that the coolant level was below Min....filled it up two days ago...looked yesterday and it's back down about a pint or so...after driving only around 50 or so miles...did you ever figure out what caused your issue?

You should never drive it below min mark. If it is low enough you risk introducing air pockets which can cause engine cracks (and much larger problems). It is possible there is air in your system and since you've added more coolant now it is able to purge this air out, thus requiring more coolant. Or it is possible you have a leak. When the car gets hot enough the bleeder valve opens by itself thus allowing the system to bleed itself to a certain degree. Or on a cold car you can manually pull up the bleeder valve to ensure it gets bled (although there are more exact procedures on doing this properly - you should search/read up on the subject). If you have a vacuum system (such as uview airlift) you can test for leaks and or use it to refill the system properly without any air. Or take it to a shop that has a vacuum system.