Hi Guys,
recently installed a test pipe and o2/dump from UR. after a few hours of driving was great, however the following day whilst cruising it displayed a cel. Should i be concerned, performance has not changed, what will it be most likely be? And how do i check what code it is..

Do CEL's clear themselves?

dz

 

No, CELs don't clear themselves unless the problem is fixed.

You should be able to go to Autozone/Pep Boys and have them read the code for you for free.

 

Seriously man, why speculate when you can just get the codes pulled in 10 minutes. Write down the codes and post them up, don't go by the generic OBD-II code standard translation, just get the code numbers (P0420 for example).

If dirveability has not changed I would expect it's a cat inefficiency code due to an issue with how your rear 02 sensor is installed. Other option would be system too lean resulting from an exhaust leak at either between the hotside and downpipe or downpipe to test pipe joints.

 

Mad_VIII is right, I had the same setup eg. UR long downpipe with O2 housing and UR high flow metal cat. got the CEL at the track the other day, error code is P0137, low votage (rear O2 sensor), cleared it and its running fine.

 

Ok, thanks for that, how do i pull the code?? what can pull the code?? Im in Aus, so autozone or pepboys is out of the question. Once the code is found how is it cleared?

 

code is P0420... cat inefficiency? what should i do considering there is no cat now? Just clear the sucker?

 

Danny - you can do a couple of things:

1) get a few spark plug extenders and put them on the rear02, this will push the rear02 out of the exhaust stream enough to stop the CEL's from popping up

2) get someone to change the ROM on your car to ignore these errors, you can do it yourself but you will need a OP2.0 cable and lots of reading

 

Cheers... will get matt to have a look at it soon... Just been reading up on it, im not too concerned. Thanks

 

btw - I wouldn't run a testpipe in Aus... at least get a HFC

 

I will be doing that very soon, i have a few metal substrate cats (unflanged and unpiped) at home, and im going to get them welded into the test pipe. Just had to get it installed. im an eager beaver..

 

Will ECUFLASH (open ecu) sort this out??? or do i still have to play around with extenders and what not.

 

well the ECU_OPTIONS_2 bit change works on my car... but others have had problems.

 

You can't just clear it. It will keep coming back. You need a CEL fix.

http://www.gruppe-s.com/Evo/evoex/05CELFIX.jpg

Or just buy a spark plug non-fouler and DIY.

 

You removed the cat and now the second O2 sensor (which monitors the health of the cat) is in free flowing exhaust, which is supposed to be blown through a cat.

Not sure why you're surprised.

Two options -

1.) Do the anti-fouler trick on the secondary O2 sensor.

2.) Get a tune that essentially ignores the secondary O2 sensor.

 

But my concern is that the UR test pipe has the fouler built into the pipe... Will it need another one to extend it out further? Is there a 'fine line' for how much further you extend the o2 sensor... Can it be extended out too much and therefore throw another code (possibly low voltage o2)?

Tune is comming, but would like to sort that out prior...