PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

codes thrown by HFC/removed cats...

Old Mar 11, 2011 | 07:16 PM
  #1  
GXPPOWER's Avatar
Thread Starter
TECH Enthusiast
 
Joined: Aug 2005
Posts: 701
Likes: 0
From: crossett, Arkansas
Default codes thrown by HFC/removed cats...

does the codes thrown by deleting or installing HFC hamper performance/retard timing, force you to run rich, or any other negative impact or is the CEL from that just a reminder "hey your not emissions legal"

and man im glad to be back in a v8!

doesnt seem anyone over in G8 land knew. figured someone here will and im sure the answer is the same.
Reply
Old Mar 11, 2011 | 07:58 PM
  #2  
BlueThunder2's Avatar
10 Second Club
iTrader: (3)
 
Joined: Nov 2002
Posts: 542
Likes: 0
From: Lubbock,TX
Default

Could make it run a little lean or rich. If you deleted them you should really get a tune.
Reply
Old Mar 11, 2011 | 08:00 PM
  #3  
GXPPOWER's Avatar
Thread Starter
TECH Enthusiast
 
Joined: Aug 2005
Posts: 701
Likes: 0
From: crossett, Arkansas
Default

oh i am. getting headers and all in couple weeks. i just want to see how my exhaust is going to sound with cats vs without once my axle back comes in. depending on that ill decide if i go with headers+offroad pipe or HFC.
Reply
Old Mar 11, 2011 | 09:36 PM
  #4  
GXPPOWER's Avatar
Thread Starter
TECH Enthusiast
 
Joined: Aug 2005
Posts: 701
Likes: 0
From: crossett, Arkansas
Default

geeze.. not sure how i can even get them off there in such weird funky positions
Reply
Old Mar 13, 2011 | 06:51 PM
  #5  
01Z28M6's Avatar
TECH Resident
 
Joined: Oct 2005
Posts: 781
Likes: 0
From: Taxme, Ohio
Default

Originally Posted by GXPPOWER
does the codes thrown by deleting or installing HFC hamper performance/retard timing, force you to run rich, or any other negative impact or is the CEL from that just a reminder "hey your not emissions legal"

and man im glad to be back in a v8!

doesnt seem anyone over in G8 land knew. figured someone here will and im sure the answer is the same.
Any DTC related to exhaust emission will ironically put your car into a rich state where stoichiometric disappears and a/f never gets above 13.5:1 while crusing. I have watched this on my wide band controller, hand scanner and scan/tune software. I'm not well versed on this but I believe certain DTCs cause the pcm to use a safe table for air, fuel and timing. I'm not positive about changes to the power enrichment tables but it only makes sense that the default computer programming will protect the engine in all situations.
Reply


Thread Tools
Search this Thread

All times are GMT -5. The time now is 09:04 AM.

story-0
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-1
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-2
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-3
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-4
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-5
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-6
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-7
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE
story-8
Five Reasons the Camaro Was the Most Pivotal Player in the Pony Car Wars 2.0

The world was a better place when it was still around.

By Brett Foote | 2026-01-23 09:20:37


VIEW MORE
story-9
10 Reasons the LS7 Is GM's Most Extreme Naturally Aspirated V8 Engine Ever

Slideshow: The 7.0-liter LS7 was designed for absolute cutting-edge performance.

By Verdad Gallardo | 2026-01-07 18:36:00


VIEW MORE