CEL w/lt headers & hf cats
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From: Big Bend Country, TX
St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15- '16-'17-‘18-‘19-'20-'21
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CEL w/lt headers & hf cats
I have Dynatech headers w/high flow cats on my '06 A6. The system throws an error code telling me I have no cats. I have it reset and, within two weeks time, it comes back on. The service mgrs at several dealers have told me the same story, the cats are working ........... to good! There are no simulators on the market yet and I am reluctant to have the CEL function shut off with a software edit as I would then not become aware of any major engine problem should one occur. My '05, M6 did not have this problem. I understand that the engine software is drastically different between the '05 and '06 yrs. Is any one else with headers on '06 having the same problem ? If so, have you solved it ? And, if so, how. I really don't want to get rid of the headers if I don't have to. However, in TX, they won't pass the car for it's annual safety insp. if the CEL is on. Wow, I can already see the parts for sale wolfs pacing outside the den window. 
Safety Car
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From: Boca Raton, FL
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
My 05 mn6 has been throwing this code multiple times over the past 18 months. Started when I put the Dynatechs on and continues repeatedly. So, I went to Wal-Mart and bought a $70 OBDII and simply clear the code.
BTW, I did have my dealer run a diagnostic and they found nothing that would indicate a CEL.
BTW, I did have my dealer run a diagnostic and they found nothing that would indicate a CEL.
Thread Starter
Team Owner
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From: Big Bend Country, TX
St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15- '16-'17-‘18-‘19-'20-'21
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Happy 4th Jeff. I to have the code reader you have. Unfortunately, it isn't CAN enabled. Heck, the dealers even had to buy new and more expensive equipment to read the '06 GM cars. The new CAN enabled reader is around $300. I've already done a web search for it. In TX, they plug into the data port under the dash. If the CEL shows that it has been shut off with fewer than a certain # of read cycles (approx 50driving miles), the car flunks ! If I have to remove the headers to pass my safty insp, they are history. The parts wolfs are circling ever closer.
Team Owner
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From: Swansea IL
Originally Posted by 4 MY EGO
The new CAN enabled reader is around $300.
http://www.diydiagnostics.com/index2.html
It's the second reader for $69.99
Tom
Safety Car
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
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From: Austin Texas
4 MY EGO; In the major cities and surrounding counties in Texas all it takes is an inspector with an attitude to fail you if you have headers. The visual part of the inspection calls for stock cats in the stock location.
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St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15- '16-'17-‘18-‘19-'20-'21
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Originally Posted by schilitj
Guess what I'm buying this weekend. Duh ! He explains to me that the reason the light kept coming back on was because the darn dealers weren't clearing the code completely out of the system. All the tech was doing was shutting off the light. Evidently there was another step they were not doing. Kind of like cleaning out unwanted cookies on a computor. To all, thank you for your help. Michael
Safety Car
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From: Boca Raton, FL
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
Originally Posted by 4 MY EGO
Amazing! I drive over to a friend's house to use his code reader to shut off the CEL. What's he use ? The Innova 3030 Guess what I'm buying this weekend. Duh ! He explains to me that the reason the light kept coming back on was because the darn dealers weren't clearing the code completely out of the system. All the tech was doing was shutting off the light. Evidently there was another step they were not doing. Kind of like cleaning out unwanted cookies on a computor. To all, thank you for your help. Michael
Guess what I'm buying this weekend. Duh ! He explains to me that the reason the light kept coming back on was because the darn dealers weren't clearing the code completely out of the system. All the tech was doing was shutting off the light. Evidently there was another step they were not doing. Kind of like cleaning out unwanted cookies on a computor. To all, thank you for your help. MichaelCorvette Stories
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Thread Starter
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From: Big Bend Country, TX
St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15- '16-'17-‘18-‘19-'20-'21
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420 and 430 if I remember correctly. Right and left cats not heating up fast enough.
Le Mans Master
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From: Chandler Arizona
I thought any normal sim would work? Do the sims not work with the 06's? Also, if you turn the code off it's the same as having the sims. I had codes on my 01 Z28 with long tubes and high flow cats and I kept clearing them with my Actron OBDII code reader. I got really tired of doing it every 3 days so I finally had the codes turned off with HPtuners. It was never an issue after that. But I know what you mean of not knowing when you have a real problem.
My 06 Vette has LG long tubes with high flow cats and knock on wood, I have never thrown a code since I put them on about 2 months ago. If they start throwing codes I'll buy HPTuners now that it's available for an A6 (for at least the engine functions).
Last thing, I read somewhere that people put in the plug saver extensions (that you buy from the HELP section at Checkers) and that sometimes keeps it from throwing codes. Never tried it, sounds kind of hokey to me, but some people say it works.
Good luck,
Glenn
My 06 Vette has LG long tubes with high flow cats and knock on wood, I have never thrown a code since I put them on about 2 months ago. If they start throwing codes I'll buy HPTuners now that it's available for an A6 (for at least the engine functions).
Last thing, I read somewhere that people put in the plug saver extensions (that you buy from the HELP section at Checkers) and that sometimes keeps it from throwing codes. Never tried it, sounds kind of hokey to me, but some people say it works.
Good luck,
Glenn
Last edited by glennhl; Jul 5, 2006 at 08:01 PM.
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Originally Posted by 4 MY EGO
420 and 430 if I remember correctly. Right and left cats not heating up fast enough.
Thread Starter
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St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15- '16-'17-‘18-‘19-'20-'21
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Originally Posted by cbrf4i1
unfortunely it wouldn't work, at least not on the 06.
I checked with A&A ............. NADA ! 
Burning Brakes
Joined: Jul 2006
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From: Southern Florida
Originally Posted by 4 MY EGO
420 and 430 if I remember correctly. Right and left cats not heating up fast enough.
Thread Starter
Team Owner
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From: Big Bend Country, TX
St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15- '16-'17-‘18-‘19-'20-'21
NCM Lifetime Member
That's why I'm leaving things as they are. In no way would I have the CEL tuned out of the system.
