I had a dynatech header/exhaust system installed at a local shop.
two days later the check eng light came on they replaced the O2 sensor
that worked for a day. now they want to replace the Hi Flo cats.
NO NO NO
I am sure someone has been down this road before.
How do I get this to work and still get thru Va insp.

Thanks
Camper

 

Just some encouragement, I self-installed the Supermaxx headers about 1000 miles ago and have never had a bad code thrown.

You need to post the codes you're getting (do a search if you don't know how to display codes through the DIC). Common problems include swapping the front and back O2 sensors and swapping the left and right rear sensors.

 

Thanks Jim
The O2 sensors are not in error only the Hi Flo Cats
I will have to find out how to getthe codes out of a 2000

 

Most C5's with headers and hi-flow cats are going to throw codes... solution 1 is to have an LS1 edit/tune down by a professional shop and they can turn off your rear O2's...which is most likely what's causing the code.(but please post up your codes to confirm) The hi-flow cats do not burn enough emissions off (hence why they are hi-flow) and this causes your Rear 02's not to read properly in line with the Front O2's..and bingo "check engine"

OPtion 2 is to buy O2 Sims, they are about 80-90 bucks a piece, they will plug in where the rear O2's go and you are set.

As Jim said, it could also be that you crossed up the O2's....but if you did that, I think you would know, the car would not idle right and you'd know it.... I am speaking from personal experience on this one ;-) as I installed the same Headers and had the same problem.

Personally- I'd go with a tune to get the max horspower out of the headers.

I am not sure what VA inspections are like....here in IL they just plug into your port and do OBDII Scan...so long as you have no codes you are fine and pass...no sniffer test, or visual inspection.

 

I have the same system Dynatech Supermaxx. I get 0420 and 0430. It is TWC (Three Way Catalyst) inefficiency caused by the cats, will not hurt the car or effect performance, just annoying. DO NOT replace the cats unless you really want to, may get rid of the codes like Jims, but Frank hit it on the head, I think.

Also, just got my VA inspection last month in Va Beach at Kramer tire (along with some Toyo T1R tires) no problem. DO NOT get inspection at stealership even if its free!! Phil at ProStreet can give you a good tune in NoVa, or Jeff at Carolina Auto Masters if you are more to the south of the state.

Good luck and hope this helps some

 

I did the Dynatech system install 3 weeks ago- Car threw codes 0134 and 0154-- insufficinet activity- cleared the codes and they re appeared- cleared them again and they haven't returned-???? one guy told me the connections might be loose?? I hope they are gone I'm going for a tune in May--that should banish those pesky codes-

PS. Love the Dynatechs!!!

 

Thanks to all
I will call phill and go for the tune. Might as well get the HP and the codes at one time.

 

I have about 250 miles on my Dynatech install on my '02 Z06 and initially I got the "lean bank" codes (0171/0174, IIRC) but they went away after a few days and have not returned. Yesterday I just got the 0420 cat codes. I will be getting them tuned out shortly... Where is Prostreet located??