Got my first CEL today after firing up the TT after work. All the idiot lights illuminated as normal but the CEL stayed lit. Car seems to run normal with no issues. Temperature during the drive home stayed normal, boost was still there, oil pressure is fine. Not sure if this a temporary hiccup, but when I got home, I turned off the car then started it again, and the light was still there.

Do I take it to the dealer or should I buy a reader to read the codes and possibly reset the computer? I read that many of you recommend the Durametric. It is a couple of hundred bucks, but if it saves me a few hundred at the dealer, it could pay for itself in short order.

Thanks,

Ken

 

My CEL came on again after having the 30k done. I suspect it has to do with the new exhaust system. At any rate, I disconnected the battery for 1/2 hour, reconnected the battery and the CEL disappeared and has yet to return after a few hundred miles. The Radio code must be re-entered when doing this...just as a heads up.

 

my recommendation is to get the codes read....however you do that. otherwise we play the game of 10000 guesses...let's see guess #1 is MAF (you have the V-flow?)

 

Yep, I have the EVO V-Flow intake. Will that cause the MAF sensor to fail? I might try to find an Autozone today and see if they will read the codes for me.

Is a radio code needed for an '04? I have gone through all my documents and can't find a radio code.

 

could be ANYTHING...my CEL came on when i needed new brake pads..

 

My light is currently on for my secondary air injection. My Indy (who read the codes for me) told me not to worry about since it's totally useless and won't affect the engine. In fact, he said the only real CEL to worry about is a blinking one which means the catalytic converter isn't working. He told me to drive it like I stole it until he can get me in to fix it. I wouldn't worry about it, but you do want to get that code read.

 

Not sure the autozone scanner will give you all the codes, but worth a try.

No radio code for 02+ as it is stored in the DME.

liquidcool...Your indy is not exactly right. there are codes which will put your car in limp. while they may not damage the car, they can effect its performance. a blinking code could be a lot worse than the cats!

 

1. Absolutely get a code reader. Even if the dealer or an indy does the work, knowing your codes and what should be done can save you aggravation and $$$.

2. Many auto parts stores will loan you a reader, some want $150 deposit. Borrow it, take it to the parking lot, read the codes, write them down, RESET THE CODES, return the reader, report back here. You'll get a good idea of what it is.

3. How many miles on the plugs? I had a single, isolated CEL that was a misfire on one cyl..... changed the plugs. It could be many things....

4. Liquid- I disagree entirely with your indy. A large number of the CEL faults will impact AFR, which in turn can damage the engine. Not immediately, but over time. For example a CEL due to an overly rich condition can increase fuel wash in the cyl wall, and fuel contamination in the oil- both increase ring wear and bearing wear- not 'engine will sieze tomorrow' but over time they will have an impact. THis is not meant to be scare tactic, but the concept that the CEL is just some 'silly emissions crap' is wrong.

A

 

Good reply, It is all to easy to disregard the CEL as the car usually will continue to run just fine. I would agree, find out soon what it is, and I would not drive it like I stole it, you never know what long term damage is being done while driving aroung and ignoring that warning the car is providing you.
Yes, it is a pain in the ***, and these cars are usually so reliable, that it is easy to treat it the same as you would the family sedan. But serious damage can result in serious heartache to the wallet.
FS

 

My bet is either O2 sensor or MAF.

 

Okay, here is the skinny. Went to Autozone and had them read my codes. This is what I have:

P0420 - 40 TWC Conversion, Bank 1 - Above Limit
P0430 - 45 TWC Conversion, Bank 2 - Above Limit

Based on a little searching, the codes appear to relate to either the cats or O2 sensors. Note that I replaced my exhaust about 1000 miles ago and used the existing O2 sensors. The cats are 200 cell and are brand new. My car has 8000 miles.

Whadya think? The car seems to run just as it did before the CEL indicator lit up.

Ken

 

You need to have your O2 sensors checked out. I do not think it's the CATS. You have 4 O2 sensors on the car, two each side. They are pretty inexpensive. Have your tuner check out the codes, I think they are the O2 sensors and it is an easy fix. Make sure keep all these codes for future reference.

Art

 

Possible fault cause
♦ Oxygen sensor ahead of and after TWC exchanged
♦ Valve lift fault
♦ Aged oxygen sensor after TWC
♦ TWC faulty

 

What are the two banks referring two? Do they refer to each exhaust? If so, I'd find it unusual that sensors failed on both sides at the same time.

So should I try to reset the codes first and see the errors pop again, or should I just take it to the dealer? I'd love to find an indy Porsche certified mechanic here in Michigan.

 

I first check to see the O2 sensors are hooked up properly, reset and see what happens.