Check Engine Light
Thread Starter
Melting Slicks
Joined: Oct 2002
Posts: 2,492
Likes: 0
From: Williamson New York
Check Engine Light
just finished putting on stainless steel braided brake lines and am getting Check engine light on- Checked codes and can't see a current code - Had tossed a code 3 weeks back after Dynatech header install but it cured itself and disappeared- Car runs fine and stops fine - brake system light??? any ideas 
Burning Brakes
Joined: Nov 2004
Posts: 993
Likes: 0
From: PA
I don't believe the CEL is thrown because of the brakes. I have heard that the SS brake lines can cause interference with the electronics on the wheel sensors.
The CEL is always (I think) accompanied by DTC(s)
The CEL is always (I think) accompanied by DTC(s)
Racer
Joined: Aug 2005
Posts: 307
Likes: 0
From: Bay Area CA
I got a CEL after installing my Dynatech LT's - it didn't show up until about a month after the install.
Here's how you can check which code is being thrown: With the key in the "on" position hold down the "options" button and press "fuel" four times in a row. You may need to have the DIC screen clear before doing this but I'm not sure. Once you do that the DIC will display all the codes your computer has stored.
The one you want to look for is P4020 which is basically saying your cats aren't doing as good as your computer would like to see them do. Anyways, to fix the problem get some rear O2 sims.
Here's how you can check which code is being thrown: With the key in the "on" position hold down the "options" button and press "fuel" four times in a row. You may need to have the DIC screen clear before doing this but I'm not sure. Once you do that the DIC will display all the codes your computer has stored.
The one you want to look for is P4020 which is basically saying your cats aren't doing as good as your computer would like to see them do. Anyways, to fix the problem get some rear O2 sims.
Le Mans Master
Joined: Oct 2005
Posts: 5,446
Likes: 0
From: Kailua HI
Originally Posted by terlox
I got a CEL after installing my Dynatech LT's - it didn't show up until about a month after the install.
Here's how you can check which code is being thrown: With the key in the "on" position hold down the "options" button and press "fuel" four times in a row. You may need to have the DIC screen clear before doing this but I'm not sure. Once you do that the DIC will display all the codes your computer has stored.
The one you want to look for is P4020 which is basically saying your cats aren't doing as good as your computer would like to see them do. Anyways, to fix the problem get some rear O2 sims.
Here's how you can check which code is being thrown: With the key in the "on" position hold down the "options" button and press "fuel" four times in a row. You may need to have the DIC screen clear before doing this but I'm not sure. Once you do that the DIC will display all the codes your computer has stored.
The one you want to look for is P4020 which is basically saying your cats aren't doing as good as your computer would like to see them do. Anyways, to fix the problem get some rear O2 sims.
Thread Starter
Melting Slicks
Joined: Oct 2002
Posts: 2,492
Likes: 0
From: Williamson New York
Checked codes in DIC- All seem to be "old" as they have the "H" after them- in any case no P4020 codes or any that refer to O2 sensors-- Just "loss of communications with just about everything- but CEL is still on?? ideas?? 
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Clear ALL of the codes! Then take her for a drive and when the CEL comes on,,,check the DIC for any DTC codes and post them. What year c5 are we working with??
Bill C
Bill C
Thread Starter
Melting Slicks
Joined: Oct 2002
Posts: 2,492
Likes: 0
From: Williamson New York
Cleared all codes with my Predator- started car --low and behold no CEL-- thanks it really helps to have so many heads helping me "keep" mine screwed on and not panic-- 
Wierd tho-- all the codes had "H' after them- I figured they were all old-
Wierd tho-- all the codes had "H' after them- I figured they were all old-
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Originally Posted by PVHolgado
Cleared all codes with my Predator- started car --low and behold no CEL-- thanks it really helps to have so many heads helping me "keep" mine screwed on and not panic--
Wierd tho-- all the codes had "H' after them- I figured they were all old-
Wierd tho-- all the codes had "H' after them- I figured they were all old-
BC
Thread Starter
Melting Slicks
Joined: Oct 2002
Posts: 2,492
Likes: 0
From: Williamson New York
I hooked up Predator to see if it would read a "current" code that maybe wasn't showing up on my DIC as current- While there I thought I'd clear em as suggested above and try again to get CEL off-- It went off as soon as I started car after clearing- so to answer your question - I would have done it thru DIC if I had started with that first- I'm just glad the damn CEL is off!! Funny cause it didn't toss any codes after Dynatech install three weeks ago- just after brake line install... go figure..
