check engine light

My check engine light came on yesterday while normal driving (nothing spirited). It was on all day and it was on again this morning for my ride to work. At lunch, I was driving and it went off? On the ride back home it is back on again. I have an appointment at the dealer for Wednesday to get an oilchange and check the codes...ever heard of something like this? I thought that once the light came on, it stayed on until the reset order was givin...???

Yup. Mine did this for CATs. Goes off and on sporadically. Tripped codes are stored, and checkups confirm this. -td

I believe most of the CELs will reset within 6 to 7 drive cycles (if the fault doesn't occur again during those cycles)

One easy thing to check-- make sure the gas cap is on correctly. (Actually saw this with my Audi; loose cap screws up pressure and CE light came on.)

And buy yourself a code reader from Harbor Freight - worth $50 to do your own diagnosis

+1 on code reader, I have an acctron unit I bought from amazon and it reads codes, clears codes, and records data while you're driving (so you can see what the sensors are seeing during a fault, adaptation values, fuel/air etc) The advice on the gas cap is actually very good, almost all modern cars have this issue with loose gas cap tripping OBD2

Go to Autozone and ask to borrow their codereader for 5 minutes. It's free.

the I replaced my bad cats the light stayed on. I disconnected the battery for about 2 minutes and it cleared.

Mine did that when the MAF was KO'd.

We'll find out the verdict tomorrow morning...I'll post the results after my dealer visit. As a side note, I just found out my aftermarket warranty expires 6/28/08 so this is really perfect timing.

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FWIW, Harbor Freight has their code readers on sale until July 4. The pocket version is $40, and the big one is $90. -td

IMHO those things are worthless...you can't read all of the codes and can't clear them all either. Just go to autozone and borrow theirs for free. If you want a Porsche diagnostic tool Durametric is the one (given you don't want to spend $$$ on a PST2 or PIWIS).

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I'll disagree with you here. 1) You can read all codes - some (generic codes) you'll get a diagnostic right on the code reader - Porsche specific codes, you look up on RennTech and get the answer that way - either way you get to know exactly what the codes mean, and you can then post here for additional forum insight. 2) You can absolutely clear codes using the ODBII Readers - of course, if the problem still exists, the codes and CEL come back - but you can clear codes and hence clear those random codes that sporadically cause CEL. 3) Having your own reader means that you don't have to drive to AutoZone every time, and you have a heads up on potential issues before you go to the dealer and get the 'widget is broken' BS. Information is power..... Durametric is nice, but cost prohibitive for many.

The dealer says the code is: Cam shaft adjustment ...bank 2 They suspect the camshaft actuator...anyone ever heard of this? They said they need to do further diagnosis to determine the exact issue. At $125 per hour, I hope it doesn't take them to long to figure it out.

I for one, have to agree on owning a 'code reader'. I have a real good OBDII reader, I got back in 2000 for one of my BMWs and it will read and clear codes as well as 'real time' reading. But it doesn't do the 'non' P code problems. My Pcar had the Airbag light come on and my problem was...."I would have to go to a Dealer/Pcar repair shop that is about 150 miles from me to find out what caused the Airbag light to come on; drive back home, 150 miles, fix the problem; drive back up to the Dealer/Pcar repair shop, 150 miles, and have the light turned off; drive back home, another 150 miles." This would be big bucks (gas and cost at the Dealer/Pcar repair shop) plus mileage on my Pcar; so I bought the Durametric tool and it paid for itself first time I used it. Told me it was the drivers seat belt buckle...cleaned the inside of the buckle cleared the code and haven't seen the light for about a Month. So, if you are like me, far from a Dealer/Pcar repair shop or don't like anyone touching your cars, then you just about have to have some type of code reader/clearer. Just my two cents worth. Good luck on your problem, Patrick

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Cam shaft actuator, lets hope it isn't that. I am sure that is not a quick fix, like a o2 or maf sensor.

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This is not correct. There are areas of the DME that can not be accessed with a generic OBD reader Again...wrong...try the airbag light for one. I agree that it is good to have your own, but there is no question as to which is the better diagnostic for Porsche. You get what you pay for.

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That is not a code, but a description of possible reason for a code. Get the actual code and we can look at it.

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He can't he doesn't have a code reader - he was told they were a waste of time...

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So last time I checked, Airbag was not an OBDII code - and did not cause a CEL. So if you'd like to differentiate between OBDII codes - which code readers can access, and other fault systems on the 996, then maybe we can be clear as to what we're talking about here. As for the OP - he had a CEL, which has an associated OBDII code or codes, which can be read and then diagnosed using an OBDII code reader.

OK, I see your point, but kind of semantics if you ask me....a code is a code...this is something reported and stored in the DME. My first post was about code readers (these are devices that connect through the OBD port). I did not differentiate between what types of codes. Again, IMHO the durametric is far superior and in the long run will cost less. It can read ALL OF THE CODES.

I think the OBD readers are great for peace of mind and can clear a lot of powertrain stuff, but they can't clear many deeper internal module issues in most german cars, for example Benz electronic transmission controllers, BAS, ESP, ABC (including the on in the tiptronic-S if I'm not mistaken) and many of the other items stated. The peace of mind I refer to means not wondering so much about whether you're seeing everything on the dealer's report, and not having to wait (often up to a week) for a service appointment to determine the fault. You know what it's saying, today, and you can move on with your life. The feature I like best in mine is that I can drive around and record the live sensor readings and adaptation values in a variety of different driving situations if there's a problem. It really helps, especially if you have a weather sensitive issue like the early stages of coil pack failure, or a CEL that may have reset itself after several drive cycles, because it also shows "pending" codes (and is the reason I quickly caught an opposite bank misfire and was able to bring it back to the dealer immediately to do the other bank). When I have a problem which isn't covered under warranty and that I can't deal with using the universal reader I have, I will definitely purchase a durametric. In fact if durametric had a universal add-on I would have purchased durametric right off the bat, but I have multiple makes and at the time I hadn't seen a CEL on the Porsche yet. In retrospect I would have purchased a cheaper reader (~40-50 bucks) and the durametric, and that would have done the job, but I spent more than I needed to on the reader. RE: the specific reader I bought, it is ACCTRON 9180 I believe, I spent ~150, and it can access and do a little more than a typical reader, wideband o2, state emissions check type stuff, but in retrospect I should have gone with a cheapo and a durametric (I'm the sort of guy who would love to have a PST2 but won't spend the money and will definitely buy the durametric when the time comes.) I don't think there's any reason not to spend 50 bucks on one of the simple ones though, just for the better sleep! I personally have already saved a LOT of money because of it, particularly on the out of warranty Benz and even the Audi, because it didn't lie to me or throw up its hands and try t replace a whole transmission or exhaust when only a wiring fault or fouled o2 was to blame, or charge me 300 bucks for diagnostic on a SPS or VAG-COM.

My cheap code reader, Autozone for $39, reads all codes and clears all codes. So worth it.

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How do you know if your reader can't read all of the codes?

I'm pretty sure that if it lights the CEL, it has to be readable and resettable with a standard OBDII reader. The airbag light isn't the CEL.

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FYI: my Harbor Freight (Cen-Tech) reader can't/won't clear a Cat O2 sensor fault. Good thing the CEL resets after a few cycles. [it did, however, identify the fault - which saved me a trip to the shop] -td

Quote: "Cam shaft adjustment ...bank 2" What were the cam timing deviation numbers? What's the mileage on the engine?

I had a similar code description on my other car. It was only a solenoid that needed to be replaced.

Maybe I should be more specific. My cheap code reader reads and clears nine hundred and ninety eight "P" codes (powertrain), as defined by the Society of Automotive Engineers. If your problem is not one of those 998 problems, maybe you should take it in to be checked out. My point being, to me personally, it's worth every penny of the $39 cost.

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My $40(Harbor freight) code reader clears all but the airbag code and has enabled me skip a dealer visit, and more than paid for the cost of acquiring it. I carry it in my car so I can focus on driving my Porsche rather than worrying about a CEL while I'm at the wheel.

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You seem to misinterpreting my point. I am very much in favor of having a code reader/diagnostic tool....I just think it is worthwhile to buy one that can do everything you need on a Porsche. The generic ones don't cut it (I tried). Get the Durametric and be done....it will pay for itself quickly. BTW, if you get a CEL while driving, unless it is flashing , the car can still be driven. If it is flashing, your generic reader is worthless. Cheers

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Actually the flashing just means you are in really deep trouble and you better pull over and stop immediately. But then again, it is possible to get one of those that is not so serious and it will clear it self up. That happened to me once. The car dried out and all was well again. As for the generic readers, they do have their limitations, but most of the time, it is all you really need unless the car has some really serious problems.

Can a durametric read other cars also?

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no, which is why I didn't buy one (I actually needed it for MB, and though heck if i'm buying a reader, might as well buy the durametric) I regret it. I should have purchased a very cheap ODB reader and a durametric, and if anything serious happened to the Audis a VAG-COM would run on the same laptop, just would need a new cable and of course the software cost. These things pay for themselves quickly when you realize what an out of warranty diagnostic will set you back.

so what was the outcome.........