ciphercong

Well it not just for a while, Two weeks ago I noticed my check engine light was on,that was just a day before I scheduled the battery replacement at a auto shop. I had the auto shop checked the code and it showed 3 codes for:

EVAP SYSTEM Large Leak
AC Switch
Fuel Level Sensor

I was busy travelling (and lazy..) so it took me 15 days before I could find a free time(today) to take it to a Porsche indy shop, and what is funny is that the light became off ever since yesterday morning, so today I cancelled the trip..

My question is should I take it as it is, or should I still go to the indy shop and have them take a look into it? For fuel level sensor there was one timeI had to jump started the car (and that's why I replaced the battery recently) and for 45 minutes the fuel level sensor didn't work. Now it works just fine..

I was told you have to have at least three codes on your car to light up that 'check engine' light? Does that mean if you have two codes you won't see a check engine indicator? Does that apply to a Porsche? By the way mine is a 2008 997 C2.

Any thoughts? Thanks !

Macster

If the shop will check for pending or permanent codes for free have the codes read just to see what if any pending/permanent codes are present.

Or you can buy an OBD2 code reader and read the codes yourself.

Permanent codes are codes that can only be removed by the DME after a number of warm up cycles with the error condition absent.

But these if present can tell you what was flagged as an error previously.

Pending codes are not yet active but are on their way to becoming active possibly. These are of interest too as they can provide an 'early' warning of a problem.

It is possible the codes were triggered by the failing battery.

That the CEL went off after you resumed driving the car probably arose from the DME recognizing the triggered error condition was no longer present after a number of warm up cycles.

That 3 codes to light up the CEL is a myth. One code can do it.

What you may be thinking of is in some areas/regions one is allowed, a vehicle is allowed, just a couple of not complete readiness monitors. Any more than a couple of not complete (or specific ones set to not complete) and the car fails emissions testing. This is true even if the CEL is not on.

saabin

Interesting you mention this.. On Saturday I replaced the battery in my wife's Nissan, and I also noticed it was due for inspection so I took it to the local place that does all our inspections.. No CEL light, but it failed the OBD scan because 2 of the sensors were in a "not ready" state.

According to the tech, it can have at most 1 sensor in the "not ready" sate in order to pass. In my case, it was the catalyst & evap.

I took it back the next day (after driving about 25 miles) and it passed, although the cataylst was still not ready.. the tech says this one can take up to 80 miles to go to a ready state after a battery disconnect.

ciphercong

Thanks for sharing this I never knew there is a difference in types of code. I was told by the auto shop who replaced my battery the code descriptions. Is it that their code reader is not sophisticated enough to identify at which phase are those codes?

I think maybe I still need to go to a Porsche indy shop to have it checked again.

Macster

The level of OBD2 code reader sophistication varies from shop to shop. Years ago when I was visiting my parents my Dad's 2004 Crown Vic had its CEL on. Of course I had my Actron OBD2 code reader handy and read the code and wrote it down for Dad. He took the car back to his "trusted" indy shop and the guy fixed the problem. Dad came back and told me the shop owner wanted to know about what I used to read the code...