wwest

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!

SOP for manual transmissions, even worse, more often, shifting into reverse when full stopped and therefore the gearbox synchronizers cannot be fully operational.

The method I use when this happens is to shift into a different, higher gear, release the clutch just lightly, enough to move the gear teeth/cogs, and then complete my shift into first or reverse. This is basically the same problem you might have shifting a true (assuming dog/spline "transfer clutch) 4X4 from 2WD into 4X4 mode while fully stopped.

I know that I have seen carpet mats molded to exact fit for an '88 Carrera, plastic/vinyl base and heel pad but with carpet (appearing) surface.

Anyone know where these can be bought..??

Original Fit Interiors in Oregon seems to be least expensive 541-459-1700

also see:

autosintl.com

Appbiz.com

gahh.com

Other than OR, haven't tried, no luck with any other of those.....

Hello guys does anyone have a laser jammer installed on there 996. Radar detectors are no match for police laser. I have a Valentine 1 that does detect laser, but once it warns you it's to late. So I have reserched the Blinder M25 Extreme. It seems to jam all police laser. (not radar) I do mostly highway driving and am taking a trip to the West Coast (2000 miles of highway one way :drive: ) and I would like to cruise at 90 mph. If you have a laser jammer on your 996 please let me know how you like it and if it is worth the money. Thanks

Don't worry about speed at that level crossing the dakotas, MT, WY, ID, but once entering WA.....

10MPH below posted speed is the only "safe" way through AZ.

When driving my car- it pulls strong all the way till about 5k rpms. At that point there is a noticeable reduction in power. I do have cel on for running lean in a cylinder (maf issue after k&n install).

Does the engine hold back timing/fuel w/cel on?

Depend on it, YES..!!

I am waiting on a replacement maf sensor right now.

Toss the K&N first, otherwise you will be wasting money on the new MAF/IAT.

I also have a question about diagnosing a bad maf:

For most cars if you start the car with the MAf/IAT disconnected you will get a CEL but the idle will be okay. Idle or constant speed cruising does not rely on the MAF/IAT functionality, only the upstream A/F mixture control oxygen sensor(s).

On the other hand disconnect the MAF/IAT(***) with the engine idling, get a CEL, and the engine will either die or idle poorly.

For many this is a simple way to temporarily disable PSM(VSC)/TC. When there is a CEL many vehicles disable these functions.

When my maf is installed and hooked up, the car holds idle fine (maybe a 200rpm fluctuation). However when I remove the connection for the maf- the car will not idle properly. Is my MAF still bad or should I see this as a sign there is another issue?

thanks!

meek

I know that I have seen carpet mats molded to exact fit for an '88 Carrera, plastic/vinyl base and heel pad but with carpet (appearing) surface.

Anyone know where these can be bought..??

I have a 1999 Carrera and recently replaced the headlights to a "Euro Effects 8000K Platinum Series Bulb" that has a draw of 55 W and output of 125 Watt. I've read the manual and it says to replace with bulbs with the same wattage, which I did. I was wondering if the 125 watt ouput would melt the housing at all. This is my first post (of many newbie questions) so sorry if this was already discussed before. Thanks for your help in advance.

KrinDot

More snake oil...

Human vision has been "tuned" to the light spectrum, centered around 4300K, of our sun over the many thousands of years we have occupied the earth. The relative wattage rating of 125 watts vs an ordinary halogen bulb might be as a result of measuring the 8000K output of the Euro Effects which have little positive effects (other than maybe impressing oncoming drivers, the majority of which you will never meet) for your human vision anyway.

Your OEM probably give you, as the driver, substantially better night vision that those "Euro Effects".

Personally I would use an isolation diode to power the footwell light from the door switch and use the extra switch to turn on only the footwell lights.

Pressure going up and down as if regulated but compressor clutch always engaged seems improbable. Some newer systems use a variable displacement compressor so the clutch, if any, is always engaged. But I don't think the '01 used that system.

A good test would be to disconnect the A/C clutch electrical connection at the compressor and see if the sound changes.

You may have a defective refrigerant pressure switch which doesn't turn off the compressor when it should, that would certainly result in some very strange noises as the liquid refrigernat reaches the compressor intake.

2000 carrera cab

My climate control has been acting strange. When the AC is on I can hear the fan running but almost no air comes out. If I hit the snowflake button to turn the AC off, cold air comes blasting out, but of course it soon gets hot.

If I hit the snowflake button again the air stops blowing but gets cold.

Assuming it takes a matter of minutes, 10-15, from the time you turn on the A/C, the flow gets cold and then stops, the evaporator is icing up.

So the AC is working. The fans are working. But when the AC is on the air is being blocked.

Any ideas?

Check the body ground post/stud for the battery negative side, just near the battery, and check the engine/body ground connection/strap near the engine, engine bottom front (I think).

I believe the bulb on 02+ headlights are different than 99-01 996's.. where can I buy higher temp bulbs?

You do understand, do you not, that higher temp (color) bulbs, above 4300-5000K, result in lower human forward vision...??

As do fog lights when used simultaneously with low beams, especially non-amber BRIGHT fog lights.

My fog light bulbs are the halogen AW, All-Weather, type and are NEVER on along with my low beams.

While quite possibly impressive and most certainly IRRITATING to oncoming drivers (most of whom you will NEVER be likely to meet and hear {or maybe "feel" in the case of irritation} their impressions) foglights along with low beams have the unique advantage of the raising the potential for putting you and you passengers at risk due to the reduction of forward vision at night.

If you must spend that money otherwise burning holes in your pockets then move the map lights to a point behind you, above your right shoulder, and change them to recessed bulb "projector" types so your passenger can read without the OEM BRIGHT map lighting interfering with YOUR forward vision.

thanks for the reply...so what next?

ofpiste;

With the A/C system under maximum "stress", max COLD, HIGH blower, open doors/windows, fresh mode, incoming HOT, >80F, airflow the low side should read about 30-40 PSI.

Common recharge method is to add refrigerant until low side pressure reaches 40 PSI or compressor starts cycling off and on, mostly ON.

Actually the current knock sensors are broadband single wire and flat response two wire knock sensors. My response is up to date. If the sensor was responded to for all harmonic frequencies

But, just as you said, the sensor does "respond" to all (harmonic??) frequencies.

Its the ECU firmware that "sorts" things, the various frequencies deemed of importance, out.

it would never allow the engine to run at it's full potential since engines harmonics are not all due to knock.

They still have their specified window!

WINDOWS, nowadays...

Therefore a base line has to be configured. Once agan a knock snsor is not the cure all!

Think this topic is worn out!

Methinks you maybe need an education in/on DSP, Digital Signal Processing. With the newer inexpensive and SUPER fast processors modern day engine control ECU firmware is well able to "sort" out the various frequencies (frequency bands, really.) and their crankshaft position, timing-related, "meaning" and react/adjust the engine control parameters accordingly.

A single day's subscription to techinfo.toyota.com and a complete and comprehensive reading about the modern day use of knock sensors in/on the diagnostic sections would probably suffice.

AND...

Why go to the additional expense of wide-band sensors if you're not going to take advantage of the new capability...??

I bow to the self proclaimed experts who know nothing about the mapping software and insist that the scanner watching the sensors tell the combustion profiles! No longer worth the discussion! Do what you like it's your vehicle!

Such a stubborn, condescending view begs for other opinions. Here's my 2 cents. It doesn't take a "self proclaimed expert" to know that there is fuel in the tank without using a dipstick. The expert can monitor the fuel level gauge and if there is no reason to disbelieve the gauge, he can tell the level from it.

Much in the same way, a "self proclaimed expert" can monitor the "combustion profiles" (boy there's a twenty dollar phrase) by monitoring knock sensors and ignition timing "profiles". The knock sensor feedback is quite simply a monitor of "There is detonation" or "There is no detonation". Period. It's quite simple and does not lend itself to any exotic study of thermodynamics, wave theory, or "combustion profiles".

I'm sure that your answer will be that I myself am also a self proclaimed expert but in fact I have gleaned this knowledge from schooling and 30 years experience engineering race engine parts and systems.

Sorry for the pointed response but your attitude begged for it.

Pointed response or not my response was based on the attitude of another!

That's interesting, you ever write any mapping firmware! Have you ever developed digital interface of OBDII diagnostics into a technician terminal. Have you ever wriiten or even seen tuning software and remote engine monitoring software?

Well I probably know the answer to that, and if you can just say that since you have a knock sensor that is the cure all, you are way off.

The limitations of the maps can only go to the a low threshold! So depending on the threshold written into the firmware will be the determing factor.

Even if the knock sensor continues to hear it does not mean that detonation will cease! A knock sensor is tuned to listen

in the 5khz range.

Aha...!

Your knowledge is out of date by a goodly number of years....

Technology has moved on.

The 4-5Khz resonant knock sensors were abandoned by most marques more than 5 years ago, probably more like 10 years for high performance cars such as Porsche. The new wide-bandwidth non-resonant sensors can not only detect knock/ping but also actually detect the initiation of the flame front and thereby determine, via comparison with the crank position sensor, if the flame front "beginning" was correctly cognizant with the spark ignition.

From reading the material on the subject it appears that if the detonation is prior to spark ignition the corrective action will be to enrich the mixture as retarding the timing would just be detrimental.

Combustion chamber cylinder bore and temperature are charateristics that vary knock frequencies. Engines typically have muliple vibrations modes. So in reality depending on the condition the design or location of the sensor may not pick up all the knock. It is not unusual for one cylinder to knock and not be detected due to the transfer function of the cylinders and engine characteristics. In addition, the base reference of the sensor has to be set low for knock detectiion above idle speed. There may be times a knock sensor to shut off above 4000rpm make more dependency on the ECU maps to prevent knock in this range. The sensor can actually not pick up 100% of the knock based on variables mentioned. So now add in 87 octane which may or may not cusae issues! Thus my point in my posts. Another point od f which I agree that a knock sensor goes from base to no knock condition, but that means nothing based on the design and other factors mentioned and if the maps cannot correct then it makes no difference if it hears it or not. The Maps are wrtten for fuel economy, emission standards and performance. With all factors considerd. The outcome is a limitation of the stock firmware.

As an engineer one would think you know this!

Nice try though!

Since this all came from someone making a mistake on using the correct octane, the article I referenced in my above posts backs that 87 octane will have it's problems in a Porsche 996.

Have a great day!

Whatever....

So let me get this straight you are comparing a Mazda CX 7 a passenger crossover vehicle vs a performance car, wow! We are talking Porsche a performace vehicle!. Once again would you really put 87 octane in Carrera turbo "street engine"?

If the tank is empty, and only regular is available, yes, absolutely YES..!!

Well if you don't know what a performane tune is, which there are many avialable for Porsche, how can you comment on the acceptable fuels to use?

NO comment.

Oh btw if I remember correctly most European countries have a minimum or "regular"@ 95 RON which is = to 91 in the US. Kinda matches the octane recommendatin in the owners manual 91 to 93!

Funny how that works out!

Yes, LOL, it is funny, truly FUNNY..

"to provide optimum performance and fuel economy Porsche recommends unleaded premium fuel with an octane rating of 98 RON (93 CLC or AKI)."

"be assured that your vehicle will operate properly with octane numbers of at least 95 RON (90 CLC or AKI)....

So, by your "standards" when we in the US fuel with premium we're really using "regular" as defined by Porsche..??

Would that mean their premium is ~100 octane....??

With that said, all I am saying is I would not make any speculation on using 87 unless Porsche says it's okay, or someone has looked at the maps! To just randomly say you can use it is nothing but speculation.

Check this out from PCA - looks like what I have been saying.

http://www.pca.org/tech/tech_qa_question.a...9-50218293CFDC}

I bow to the self proclaimed experts who know nothing about the mapping software and insist that the scanner watching the sensors tell the combustion profiles! No longer worth the discussion! Do what you like it's your vehicle!

Okay, question for you, then.

With the A/F mixture and ignition timing "mapping software" so easily malable/modified and regular fuel less expensive and such a common thing why wouldn't the parametric mapping ALWAYS allow for the use of regular fuel. What's the harm...??

Wouldn't it take a somewhat idiotic engineering team, engineering management, to overlook such capability..??

Allow an engine, "street" engine, to be damaged as the result of an owners simple oversight/mistake...??

NOT..!!

No because they already specified the fuel that should be used! Porsche and other performance cars are fighting the battle between performance and emissions! To just say you can use this fuel and to design

with such wide paramaters is a false understanding!

Yes, all of <6% between 87 and 92 octane..!!

It's a myopic view to think it's as easy as your comment!

Those who buy these cars are expeced to want the performance,

therefore the price of fuel is not a factor.

In our travels throughout europe fuel price, while SUPER expensive even for regular, was not the issue, availability of premium was.

If that is your concen then go buy a honda!

With your logic on street engine, then 87 must be okay in a non natually aspirated street engine too?

Again, other than designed strictly for race use, yes.

Take, for example, the Mazda CX-7 turbo 4 cylinder, recommended fuel is premium, minimum fuel octane is 87. Stated right there on their home page.

Hey the guy made a mistake and put in the wrong fuel!

Go try and get a warranty claim done if it's found out the so called street engine did not use the recommended fuels!

BTW when you go get a tune, guess what, they tune to the fuel being used.

What tune, which modern day street use car requires a "tune"...??

So turn the question around, if you get a performance tune what makes you think you can step down from the design? It is a bad assumption on your part!

So to respond on your comment NOT! Nice try though!

"if you get a performance tune..."

Pardon my ignorance but I have no idea what you mean by that, with today's engines just what is, what consitutes, a "performance tune"..??

I bow to the self proclaimed experts who know nothing about the mapping software and insist that the scanner watching the sensors tell the combustion profiles! No longer worth the discussion! Do what you like it's your vehicle!

Okay, question for you, then.

With the A/F mixture and ignition timing "mapping software" so easily malable/modified and regular fuel less expensive and such a common thing why wouldn't the parametric mapping ALWAYS allow for the use of regular fuel. What's the harm...??

Wouldn't it take a somewhat idiotic engineering team, engineering management, to overlook such capability..??

Allow an engine, "street" engine, to be damaged as the result of an owners simple oversight/mistake...??

NOT..!!

This is all speculation, anyone without seeing the maps to say the computer will detune to 87 is just making assumptions. I believe it will to 91 but since the recommended is 93, I would not make that assumption!

I know for a fact that maps that I was involved with Ford and GM, the threshold was not that robust to allow such a wide margin of error. Yes it will attempt to retard the spark, and adjust the fuel flow, but some maps are not that robust to get you that far below the recommendation.

You really don't need to take the time to tell us just how far behind the technology "curve" Ford and GM are, we're all, hopefully, very well aware of that. Even my '92 LS400, with the old style resonant knock/ping sensors, has enough range to adjust for regular fuel.

Based on the lower limit of not allowing it to detune that far it can only offset some detonation.

BTW on some cars high speed detonation may not even be audible!

So unless someone can show the actual fuel map. I would not speculate on anything!

And just how many of us out here in the peanut gallery do you think would even understand the actual fuel map....??

So why take a chance!

And wouldn't it be somewhat idiotic for Porsche to design a car that didn't have enough parametric mapping range, A/F mixture and/or timing adjustment, for use in a country/region/continent where premium fuel is often not available...??

I accidently filled up with regular unleaded (87 octane) rather than the recommeded super unleaded (91 octane). I know the computer will adjust the timing so that the engine will run on lower octane (albeit with less HP), but will the prolonged period of running a full tank of 87 hurt the engine in any way?

The 996 owner's manual says that the car will operate normally on at least 95 RON (I think 87 octane is about 91 RON?), so that doesn't sound good. Should I siphon out the gas?

Accoding to what I was told at the factory when I picked up my '01 the engine ECU compares the initial detonation, detected via the newer (then) wide-band non-resonant knock/ping sensors, with crank timing to determine if any corrective action is required/needed. If the (even minor) detonation is prior to the spark ignition then the mixture will be enriched since it would make no sense to adjust the ignition timing.

I was told that in my travels I would not always be able to fuel with premium and that wouldn't be a problem but I was to absolutely avoid fueling with leaded absent encurring a fee to install new catalytic converters prior to US shipment.

Hi from Saudi Arabia! I have a 2004 996 4s and it is a joy to drive. It is my daily car and drive around in temperatures of 47c. I have taken this car to Bahrain and back averaging 200kph there and back. This is a strong car! But the only issue I get is that the PCM comes up with a message saying that its shutting down due to overheating in 10 seconds. I took the car to porsche and they said everything is fine !

Does anyone know how to get around the issue?

Did you by chance mean to say PSM....??

All PSM fuctionality is provided by the ABS hydraulic pumpmotor and it will shut down due to overheating, or the potential for, really.

As I have said before, you might find someone with the knowledge and willingness to modify your ABS system such that it does not activate at all unless PSM indicates that your car, under braking, is not following the desired "line". That would give you total and complete control of braking until actual loss of directional control is threatened, impending.

If you change the compressor, you should also change the dryer.

I believe you charge on the low pressure line, which is the smaller one, but you can't just put coolant in. You need to pull a deep vacuum on the system first.

Yes, you add refrigerant via the low (<50PSI) pressure line, but I suspect in this case (if not all) the low pressure (vapor) line is the FAT one. Note that the pressure sensor/switches is in the smaller line where it can be used both to turn off the compressor once the high pressure side reaches the upper limit and prevent the compressor from operating if the system pressure is too low.

You can add refrigerant as a test without "pulling" a vacuum on the system. But in the normal case the only reason you should need to add refrigerant is because the system has a leak somewhere.

Good catch. Although, I'm sure he would have figured out the small one was high pressure when it started spraying at him. lol

Do you mean "spraying at him" as in the retail refrigerant filler can exploding due to the design pressure being dramatically exceeded..?? :rolleyes:

If you change the compressor, you should also change the dryer.

I believe you charge on the low pressure line, which is the smaller one, but you can't just put coolant in. You need to pull a deep vacuum on the system first.

Yes, you add refrigerant via the low (<50PSI) pressure line, but I suspect in this case (if not all) the low pressure (vapor) line is the FAT one. Note that the pressure sensor/switches is in the smaller line where it can be used both to turn off the compressor once the high pressure side reaches the upper limit and prevent the compressor from operating if the system pressure is too low.

You can add refrigerant as a test without "pulling" a vacuum on the system. But in the normal case the only reason you should need to add refrigerant is because the system has a leak somewhere.

you need to replace both, the compressor and the clutch. The clutch has been damaged trying to turn a frozen compressor.

Rick

99 996C4

87 044S

"trying to turn a frozen compressor...."

No, maybe not.

For some reason there seems to be a "spat" of electromagnetic clutch failures recently apparently due to the epoxy material surrounding the electric coil having not completely cured and then melting under use and engine compartment heat.