C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

Loose plugs and error codes

Thread Tools
 
Search this Thread
 
Old May 23, 2023 | 10:33 AM
  #1  
by667's Avatar
by667
Thread Starter
Heel & Toe
 
Joined: Apr 2023
Posts: 21
Likes: 0
From: Quebec, Canada
Default Loose plugs and error codes

Hello, I have 81/4 spd stock except the q-jet was replaced by a Holley and air pump removed (previous owner). I have error codes 21 (TPS-throttle position sensor) and 23 (mixture control solenoid). Do you know what those loose plugs were used for (I guess it was carb info to ecm..). Do my errors codes related to the missing air pump and the missing q-jet? Thanks!

Last edited by by667; May 23, 2023 at 01:49 PM. Reason: correction on error code 23
Reply
Old May 23, 2023 | 10:45 AM
  #2  
calwldlife's Avatar
calwldlife
Team Owner
15 Year Member
Loved
Community Favorite
Top Answer: 1
 
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
Default

uh, yes
Reply
Old May 23, 2023 | 10:48 AM
  #3  
MelWff's Avatar
MelWff
Race Director
15 Year Member
Liked
Loved
Community Favorite
 
Joined: May 2006
Posts: 18,626
Likes: 2,553
Default

You also should no longer have the stock distributor. Does your distributor have a vacuum advance diaphragm?
How are you activating the lockup torque converter?
Reply
Old May 23, 2023 | 11:15 AM
  #4  
calwldlife's Avatar
calwldlife
Team Owner
15 Year Member
Loved
Community Favorite
Top Answer: 1
 
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
Default

remove ecu fuse
your orig distributor will only give you @6 to maybe 8 deg of advance total.
it needs computer to give more so your performance is way down.
a vacuum distributor will give you , ****, like 40--+
Reply
Old May 23, 2023 | 11:30 AM
  #5  
by667's Avatar
by667
Thread Starter
Heel & Toe
 
Joined: Apr 2023
Posts: 21
Likes: 0
From: Quebec, Canada
Default

yeah, i'm a bit confused about that... I have the original dist (no vacuum, no weights). My timing adv numbers are: 12 deg@900 rpm, 24 deg@2000 rpm and 30 deg@3000 rpm. So I guess the ECU is able to do some timing advance without the q-jet info...???
Reply
Old May 23, 2023 | 11:44 AM
  #6  
MelWff's Avatar
MelWff
Race Director
15 Year Member
Liked
Loved
Community Favorite
 
Joined: May 2006
Posts: 18,626
Likes: 2,553
Default

Originally Posted by by667
yeah, i'm a bit confused about that... I have the original dist (no vacuum, no weights). My timing adv numbers are: 12 deg@900 rpm, 24 deg@2000 rpm and 30 deg@3000 rpm. So I guess the ECU is able to do some timing advance without the q-jet info...???
Apparently yes, but at cruising speeds, 3k rpm, 46 to 48 would be typical with vacuum advance, 36 mechanical the rest vacuum.
Reply
Old May 23, 2023 | 12:02 PM
  #7  
calwldlife's Avatar
calwldlife
Team Owner
15 Year Member
Loved
Community Favorite
Top Answer: 1
 
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
Default

Originally Posted by by667
yeah, i'm a bit confused about that... I have the original dist (no vacuum, no weights). My timing adv numbers are: 12 deg@900 rpm, 24 deg@2000 rpm and 30 deg@3000 rpm. So I guess the ECU is able to do some timing advance without the q-jet info...???
wow, I am surprised.
Better than I thought.
thats driveable.
computer doing work.
thanks for the info
Reply
Old May 23, 2023 | 12:17 PM
  #8  
calwldlife's Avatar
calwldlife
Team Owner
15 Year Member
Loved
Community Favorite
Top Answer: 1
 
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
Default

the throttle position code needs a carb with the rheostat
the map code is curious, it is drv side fire wall with a small vac hose and
should affect timing.
maybe someone figured out that unplugging it makes comp add timing?
very interesting.
Reply

Get notified of new replies

To Loose plugs and error codes

Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

 Michael S. Palmer
story-1

10 Revolutionary 'Corvette Firsts' Most People Don't Know

 Joe Kucinski
story-2

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
story-3

2027 Corvette vs The World: Every C8 vs Its Closest Competitor

 Joe Kucinski
story-4

10 Most Common Corvette Problems of the Last 20 Years!

 Joe Kucinski
story-5

5 MOST and 5 LEAST Popular Corvette Model Years in History!

 Joe Kucinski
story-6

2027 Corvette Buyer's Guide: Everything You Need to Know!

 Joe Kucinski
story-7

10 Things C8 Corvette Owners Hate (But Won't Tell You)

 Joe Kucinski
story-8

10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!

 Brett Foote
story-9

Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)

 Joe Kucinski




All times are GMT -4. The time now is 01:44 AM.

story-0
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-1
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-2
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-3
2027 Corvette vs The World: Every C8 vs Its Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-24 16:12:42


VIEW MORE
story-4
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE
story-5
5 MOST and 5 LEAST Popular Corvette Model Years in History!

Slideshow: 5 most and least popular Corvette model years.

By Joe Kucinski | 2026-04-08 13:25:01


VIEW MORE
story-6
2027 Corvette Buyer's Guide: Everything You Need to Know!

Slideshow: 2027 Corvette buyer's guide

By Joe Kucinski | 2026-04-17 16:41:08


VIEW MORE
story-7
10 Things C8 Corvette Owners Hate (But Won't Tell You)

Slideshow: 10 things C8 Corvette owners hate, but won't tell you.

By Joe Kucinski | 2026-04-01 18:36:07


VIEW MORE
story-8
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!

Slideshow: Should you add one of these incredible Corvettes to your garage?

By Brett Foote | 2026-04-01 18:14:05


VIEW MORE
story-9
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)

Slideshow: Every Corvette Grand Sport explained

By Joe Kucinski | 2026-03-26 07:13:44


VIEW MORE