zoomsan

Car was slow to heat up to operating temp, slow to react to increased temps and slow to cool back down. Temps are now much more stable and consistent.

I couldn't see any obvious signs of damage/defect on the old tstat but its clear that the change has improved things.

Still recommend replacing the hoses while you're down there. I'd have saved a lot of time and aggravation if I'd been able to just cut off the hoses. Its tight down there and tough to get a grip on the larger/upper hose. Ultimately, I had to remove the thermostat housing to get the upper hose off.

I'd also recommend getting a hose clamp to keep from losing as much coolant as I did during the process.

Hi,

Since your original post, I was hoping someone would have put up their procedures for the Thermostat replacement. Unless I'm missing it, I don't see it. I've searched the forums and can pretty much piece together things, but would you happen to have the actual procedures from Loren? Just want to make sure I'm identifying the correct location, hoses, etc. Thanks!

Has anyone considered using airplane paint stripper? This should be available at auto parts stores. Gritblasting will remove a lot of of the material and clean it up, but if there's a chemical solution that won't damage the alloy, why not use it? Especially, if the wheels are aluminum with an anodized coating. The chemical strip won't remove the anodization. The chem strip would be a lot less hands on, but would definitely take more time to remove the paint.

Yeah, it could be the smog / air pump. Especially if it is cold. Sometimes it sounds like either a big vacuum pump or like a table saw / high pitched whine of a jet engine.

Do you hear this sound after driving the car around for half an hour, turn it off, and then turning it back on?

It's the horrible shrieking sound for a second or two at start-up when cold. I have to check the starter first and see

if that is the problem.

Thanks guys for your help

Kristian

Hi...any luck in finding out if your problem was caused by your starter?

Thanks a bunch, guys! All great suggestions and I will try the tests suggested. Looks like there are a couple of different schools of opinion, so I'll take the most cautious one.

At least there is some explanation and I'm not the only schmuck doing this or experiencing this.

Approximately the same thing happens with my stock trans. It's happened on other cars as well. Since it happens rarely, I didn't figure any kind of adjustment would help. I just try to be gentle with it, put it back into neutral, then shift in again. Some of the older transmissions did much better if you shifted from neutral into 2nd, then move it into first. I haven't had that experience in the 996 -- but you could try it.

Thanks for the advice. I've been given the same advice and will probably do it, but I'm still not satisfied that something like this shouldn't be happening IF the transmission is OK. If there is something wrong with the tranny, I'd prefer to knock it out before things get too bad.

Do you have an aftermarket shifter?

I have a stock shifter. Actually thought about switching over to a new shifter, but didn't think it would help much.

Hi Everyone,

Every now and then when I'm at a stop and shift from neutral to 1st gear, it's a little difficult to get it into gear. Sometimes I'm able to kinda force the stick into gear, but most of the time, I need to put the transmission back into neutral, lift my foot off the clutch, depress the clutch, and try shifting again. 8 out of 10 times I'm able to get it back into 1st gear. Is this a sign of something horrible about to happen to the transmission?

I have 48k on my 99 C2S and other than this, have no other issues with the clutch or transmission. In general, shifting to the other gears is smooth.

Any info is greatly appreciated. Thanks!

Ok got this tested the right way. Just removed one of the low speed relays then turned the a/c on and just one fan ran on low speed. A few seconds later then went to high speed and both ran. I guess I had never heard them on high speed, cause they are significantly louder and obviously they move more air. So all is good the noise I was hearing before was the fans on low. Thank you all for your help..

:renntech:

Hi...so did you not try the jumpering suggested? All you did was take out 1 low speed relay and the car automatically kicked into high speed? Just curious if this is an easier way of seeing low/high speed fan flow differences. I guess a lot of people seem to confuse the low for the high.

What year and model 996 do you have? I verified Lorens temps with the Streather book, but that doesn't mean that they are correct...maybe 102C is not high speed for newer models, but low speed...his book has a few errors w/regards to info for pre-face lift cars vs post facelift, but I'd be surprised on that one. 102C is like 216F..., about right for high speed kick on...but the newer cars do run cooler, so who knows. Is that with your AC on or off? Actually, wrong question, because at those temps the high speed should have already kicked in regardless! That is just way too high if the low speed fans are just kicking on. Really sounds to me like the high speed circuit or the temperature actuation isn't working on yours, doesn't it? You really need to jumper the relay base pins to be sure.

I haven't tried stop and go, ( like a Beltway or 95 backup) w/o AC, and there just is never really any S&G traffic in Richmond except 95 at 5:00, and I'm never in it. I know that if I run errands with a lot of S&G around town (lights, stop signs, etc) with AC on, my gauge goes from exactly between the 8 & 0, to a touch more on the 0, which, according to the Autoenginuity software is about 190 to 195. I haven't run errands in 100f weather w/o AC!! But if it's 80F out, like some recent mornings, I have and the temps go only a little higher...still no fans. If those AC fans are running, the hot air wash that comes out directly in front of the front wheels is scathing hot. I haven't put a thermal probe on it, but based on my work around hot air & boilers, I'd guess it is around 160 - 170...really hot. You may have a weak fan or some blockage between the rads and condenser. Like I said, after 38k miles, mine was full of crap, probably 1/4 to 1/3 blocked each side

Thanks alot perrinva! You're advice is really helpful. My car is a 99 C2. But, based on some of the descriptions you are saying in your post above, my car seems to be running "normal" with the exception of the low speed fans kicking on. I'll have to give a shot with jumpering out the relays to see the sound and airflow difference between low and high speed to understand what everyone else is talking about. I've already cleaned out my radiators and I think it has helped a little, but not a lot. Since I've never jumpered out the relays, can you please help provide me some guidance? How are you doing it? Are you removing the relays from the sockets and jumpering it out from there? Also, which particular sockets are you jumpering from/to? Thanks again!

I have a 02 Carrera cabriolet with 32K and a manual transmission. The car is currently in my local dealers shop for repair of the rear main seal and water pump. My service adviser “highly” suggested that my clutch needed to be replaced. The adviser stated the clutch is going to fail in the near future and we should change it out while the transmission is out of the car.

I’m not an aggressive driver, but it seems premature to change out a clutch at 32K. Information I’ve found indicatea clutch life is typical “between” 50K-70K?

I’m going to closely inspect the old clutch when it is removed, what clutch disk characteristic should I be looking for or disk dimensions measured to determine excessive wear or impending failure?

Thanks

Rick

If you plan to keep the car for a while, better to pay for the $500-600 now to have this replaced, rather than the $2200-2500 to have it done in the future. Most of the labor is already taken care of during the RMS change.

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Just the opposite. AC on is low fan mode, ie the series resisitors are switched in. They get smoking hot. >102C is high speed. Only time I've ever seen high speed is by jumpering the relays. Talk about loud fans!

Thank you very much for the input! But, I admit I am a bit confused now. Using the OBD hack, I monitor the coolant temp and when it's > 96C, nothing happens. But, when it's > 102C, the fan kicks on, which seems to blow at the same speed & move the same amount of air as when I turn on the AC. I have swapped relays, so I believe they are OK, but have not tried jumpering them and have not been able to verify impedance (missing the test equipment).

So, be this the case, when the fan blows with the AC on or what I'm feeling @ > 102C, is it really "low fan mode"?? Or is it that the "high fan mode" kicks in at a even higher temp than 102C??

I have a 2002 c2. Older cars may be different. On my car the AC is definitely the low speed. Easy to tell because A. The resistors are burning hot, so they are "in" the circuit. B. I've jumpered the inputs at the relay, and it is easy to tell the high speed fan vs the low speed ie resistors "out" of circuit. The 2002 and newer cars have a newer rev of the DME, and the OBD hack does not work. (BTW, I assume you mean the HVAC hack, not the OBD. if there is an OBD hack that works on newer cars, I'd like to know what it is!!) I have never been able to verify that the temp switches work. When I get a chance, I hope that my Autoenginuity software will allow me to force them on. I just haven't had time to try it out yet. I've had the car since March, and had to replace the drivers side series resistor, because it was burnt out. Noticed it when on a warm 85F day, w/o AC on , I heard the passenger side fan come on, but not the drivers side. Pulled off the bumper cover, cleaned out TONS of crap from the rads and between rad & condenser and replaced the resistor. Both fans come on with AC and when checked with jumper, but so far have never come on due to coolant temp rise! Maybe this week..it's supposed to be 100F all week.

Thanks for the advice! Will try the "temp test" on the resistor with the fans on.

I also saw your post on another topic and you mentioned that you couldn't get the car to go above 96C with sprited driving with the 100C weather we've been getting in VA. That kills me because I can maintain <96C (via the HVAC hack) with consistent highway driving, but the temp will go up to 103C in stop and go traffic on 90+ degree days.

So if I want to evacuate the hot air out of the engine bay, I could turn the a/c on to run the fan?

Sorry...I'm referring to the radiator fans. The engine compartment fan is a different beast. There's a post here on how to do a mod, if you want to manually turn on your engine bay fan....post #13

http://www.renntech.org/forums/index.php?showtopic=20479

Fan speeds and switch on tests are covered here.

I can get to the ballast on my car without removing anything - from the bottom.

Thanks Loren! Much appreciated!

The info on Renntech is really right on, but this particular subject has confused me a bit because I see some conflicting posts. Some people say high speed doesn't come on with AC, others say it does and stage 1 is low speed and stage 2 is high speed, but AC comes on stage 1....not sure who's right. Whatever the case, I'm starting to feel more and more that the ballast is kaput, but wanted to confirm w/ every check I can (without having the ability to verify the electrical conductance), before moving to getting the part or bringing to the shop.

Thanks again!

Electric fan, speed 1

Coolant temperature higher than 96.75° C or air conditioning switched on.

Electric fan, speed 2

Coolant temperature > 102° C or air-conditioning fluid pressure switch closed (coolant pressure > 16 bar).

The electric fans for the radiators are only triggered when the engine is running.

Hi Loren,

Does Electric Fan Speed 1 equate to the "high speed" fan speed (i.e. stage 2....relays 20,22) and Electric Fan Speed 2 equate to the "low speed" fan speed (i.e stage 1....relays 19,21)?

Thanks!

Just the opposite. AC on is low fan mode, ie the series resisitors are switched in. They get smoking hot. >102C is high speed. Only time I've ever seen high speed is by jumpering the relays. Talk about loud fans!

Thank you very much for the input! But, I admit I am a bit confused now. Using the OBD hack, I monitor the coolant temp and when it's > 96C, nothing happens. But, when it's > 102C, the fan kicks on, which seems to blow at the same speed & move the same amount of air as when I turn on the AC. I have swapped relays, so I believe they are OK, but have not tried jumpering them and have not been able to verify impedance (missing the test equipment).

So, be this the case, when the fan blows with the AC on or what I'm feeling @ > 102C, is it really "low fan mode"?? Or is it that the "high fan mode" kicks in at a even higher temp than 102C??

Electric fan, speed 1

Coolant temperature higher than 96.75° C or air conditioning switched on.

Electric fan, speed 2

Coolant temperature > 102° C or air-conditioning fluid pressure switch closed (coolant pressure > 16 bar).

The electric fans for the radiators are only triggered when the engine is running.

Hi Loren,

Does Electric Fan Speed 1 equate to the "high speed" fan speed (i.e. stage 2....relays 20,22) and Electric Fan Speed 2 equate to the "low speed" fan speed (i.e stage 1....relays 19,21)?

Thanks!

Hello Everyone,

I'm not sure if I'm looking at this incorrectly or not, but is there a quicker way to access the radiator fans and it's components other than taking off the bumper or wheel wells? I know removing the fans would require taking off the bumper, etc. but just simply getting access to the ballast resistor, etc.

Also, how noticeable are the fan speeds to one another. I'm in the same boat as owners who have seen the temp gauge creep past the "0" on the 180 at stop and go traffic. The fuses are OK, but I need to verify the relays are OK. I turned on the AC and had the fan blow and assumed this was the "high" speed....I can really feel the air flow. And I saw Loren mention that the fans run at high speed with the AC on, but noticed on the following post:

http://www.renntech.org/forums/index.php?s...iator+fan\

the fans don't come on high speed just because the AC is on. Who's right?? Or am I misinterpreting the info? Also, how much air should I expect to move at "low" speed.

Thanks for any advice!

I recently bought an Arctic Silver 1999 966 C2 coupe and, so far, no buyers remorse. :) I'm going to need tires in the next few months. The car has 18" wheels and currently running Michelin Sports.

I am far more interested in ride and quietness rather than performance. This is mostly a city car.

Your thoughts and suggestions would be greatly appreciated.

bolobar

Try Tirerack.com....good selection and feedback on tires. I ended up getting the Bridgestone Potenza's as well. Some may complain about the noise versus other models, but the Bridgestone's are a great value from a good tire company. Besides, mine are all seasons which will probably make more noise than others.

Relays and fuses all checked out. I took it into the dealer thinking the resistor would be the culprit, but it turns out I need whole new fan. So that's the end of the story, for whatever use it may be to others. Two thoughts:

Knowing how to get the actual temperature reading from the OBD was very helpful to me. Without that trick and this forum, I might never have realized I had a problem.

And I'm going to assume that spending a bunch of time running at 105-108 C won't have any long term ill effects? If something was going to go boom, it would have by now?

Thanks to those who replied.

Hi...would you mind elaborating on the OBD hack? I tried a search and couldn't ID how to do this. Thanks!

may i suggest....

http://www.540i6.com/ultimatecupholder.html

Nice cup holder, but if you're short and have to move the seat up close....the cup holder doesn't work out so nice. It will get in the way of the seat. Nearly got one, but ended up going through the entire OEM cup holder mod.

Thanks for the advice. No real damage on the car. I was just looking to try to get the "new car" shine back in the car. It's a 99 and showing some age. I think I can see where it looks like the clear coat is starting to wear down. Overall, the paint is fine, but I know I can't get the shine it used to have when it was brand new with wax.

What kind of damage do you have on your paintwork?

The only thing that can be removed by buffing (= polishing, does not include any new layers of clearcoat) are superficial scratches. The puffing is not used when a piece will be repainted , but rather the surface will be matted so the paint/clearcoat will adhere.

Saludos

Kare, Spain

Hello,

Can anyone recommend a good paint shop in the Northern Virginia area? I'm just looking to repaint (same color) and put a couple layers of clear coat.

Actually, is it possible to just buff off the current clear coat and put on a couple new layers without having to repaint? (Sorry....know nothing about repainting cars)

Hello,

Can anyone recommend a good paint shop in the Northern Virginia area? I'm just looking to repaint (same color) and put a couple layers of clear coat.

Actually, is it possible to just buff off the current clear coat and put on a couple new layers without having to repaint? (Sorry....know nothing about repainting cars)

I currently use Shell, but would use Chevron if it was more readily available in Northern VA.

A friend of mine said she had injector problems with her truck. Once she started using Chevron, the problems when away. Apparently, Shell and Chevron's additives really help the car's overall performance.

Hi All.. does any of you guys know a good trustworthy indie porsche specialist in northern VA area? Thanks in advance...

Hph

Intersport is good....if you want to head out to Manassas, there's Convenience Car Sales, as well. I've tried both sites at some minor level and they both seem pretty good and responsive.

Hello,

Could someone please let me know the code for my radio? The information is:

Type 4362

S/N X5017838

47/98

Thank you so much for any help! Happy holidays!

Try 8951

or 8949

Thanks Loren....you and RennTech are the best!!! Have a great holiday!

Hello,

Could someone please let me know the code for my radio? The information is:

Type 4362

S/N X5017838

47/98

Thank you so much for any help! Happy holidays!