CEL after header install
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CEL after header install
So... After 16 hours of wrenching, I have finished installing my long-tube headers and x-pipe.
I drove the car for about 45mins, and BOOM.. Check Engine Light comes on. I scanned it when I got home, and sure enough it was complaining about low catalyst efficiency.
What did I miss? I installed O2 spacers on the 2 downstream O2 sensors....
I drove the car for about 45mins, and BOOM.. Check Engine Light comes on. I scanned it when I got home, and sure enough it was complaining about low catalyst efficiency.
What did I miss? I installed O2 spacers on the 2 downstream O2 sensors....
Team Owner
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From: cookeville tennessee
I put the LG LT headers on my car with LG mid pipe also. pulled off the back cats, but did get the front cats from LG my check engine light also came on. My car was running way to rich but I put on the above also put in the car cold air box & T.B. spacer.Now my car is running better and faster also plus I check plugs now the plus are not running black & rich now running light brown.
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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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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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Only way to loose the CEL using long tubes is a tune. That is why I went with mid length. No tune !
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O2 spacer is designed to pull the oxygen sensor farther from the exhaust for use when deleting cats on a car. It tricks the o2 sensor into thinking there is still a cat by reducing the amount of air the downstream sensor reads. I've used these on several of my cars in the past with no issue. This is the first time it didn't seem to work and car got a CEL.
Here's an example of one:
https://www.amazon.com/dp/B00OXWZ60A..._uJP5wbTGC5VHF
I also installed a wideband O2 sensor for monitoring my air fuel ratio's. I haven't started logging of the car yet to see if it's picking up any knock, but initial air fuel doesn't seem bad. Are people only required to tune with long tube headers just because of the check engine light? Or is there actually a problem with knock because of changed load? With the weather being crappy the next few days, I won't get a chance to get out and log the car, so it will stay parked for now
Here's an example of one:
https://www.amazon.com/dp/B00OXWZ60A..._uJP5wbTGC5VHF
I also installed a wideband O2 sensor for monitoring my air fuel ratio's. I haven't started logging of the car yet to see if it's picking up any knock, but initial air fuel doesn't seem bad. Are people only required to tune with long tube headers just because of the check engine light? Or is there actually a problem with knock because of changed load? With the weather being crappy the next few days, I won't get a chance to get out and log the car, so it will stay parked for now
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St. Jude Donor '11-'12-'13-'14-'15-'16-'17-'18-'19-'20-'21
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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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Seems to be long tube headers only.
Last edited by MikeyTX; Mar 14, 2016 at 07:11 AM.
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Everyone keeps saying "needs a tune". I understand that, but can someone please elaborate on that? Does the car just need the CEL disabled from the ECU, or are there actually driving/load parameters that need to be modified. Since the car will be parked the next few days before I can take it out and data log it, I can only speculate right now.
Thanks
Thanks
Racer
Joined: Dec 2006
Posts: 277
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From: Jamison PA
Everyone keeps saying "needs a tune". I understand that, but can someone please elaborate on that? Does the car just need the CEL disabled from the ECU, or are there actually driving/load parameters that need to be modified. Since the car will be parked the next few days before I can take it out and data log it, I can only speculate right now.
Thanks
Thanks
Safety Car
Joined: Sep 2006
Posts: 4,364
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From: Greer, SC
Everyone keeps saying "needs a tune". I understand that, but can someone please elaborate on that? Does the car just need the CEL disabled from the ECU, or are there actually driving/load parameters that need to be modified. Since the car will be parked the next few days before I can take it out and data log it, I can only speculate right now.
Thanks
Thanks
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From: Manassas Park VA
St. Jude Donor '07-'08,-'13-'14, '16-'17
Your car is running Lean...Tune it before it blows up on you
and not a hand held tuner either...call Chris or Mike at ECS
You have to have a Tune with Long Tube Headers...
Regards
Chip
and not a hand held tuner either...call Chris or Mike at ECS
You have to have a Tune with Long Tube Headers...
Regards
Chip
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Last edited by CCA Corvette Parts; Mar 14, 2016 at 11:57 AM.
Burning Brakes
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From: Red Bank NJ
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Guys... I have a tuner. I picked up an HP Tuner setup and have the car parked. I haven't been driving it aside from a trip around town light throttle. I can tell you that based on the wideband readings I was seeing though, the car didn't seem to be running dangerously lean. I was simply asking what is the reason for needing a tune. I appreciate the input and don't plan on beating on the car until I do some data logging and tuning.
Last edited by CTWhite16Vette; Mar 14, 2016 at 12:37 PM.
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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They will need to be turned off. The reason I said tune it is at that point, one might just as well go for the entire enchilada rather than a bite.
Drifting
Joined: Dec 2012
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From: MI
Guys... I have a tuner. I picked up an HP Tuner setup and have the car parked. I haven't been driving it aside from a trip around town light throttle. I can tell you that based on the wideband readings I was seeing though, the car didn't seem to be running dangerously lean. I was simply asking what is the reason for needing a tune. I appreciate the input and don't plan on beating on the car until I do some data logging and tuning.
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