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

C3 engine cutting off when fully kickdown

Thread Tools
 
Search this Thread
 
Old Nov 8, 2013 | 04:39 PM
  #1  
Mohamed's Avatar
Mohamed
Thread Starter
Intermediate
 
Joined: Feb 2013
Posts: 30
Likes: 0
Default C3 engine cutting off when fully kickdown

I have a cutting off problem when I fully kickdown my 72 C3, it cut off just some seconds after kicking down full accelerator. Is it due to carberator (fuel) or electrical issue? Please advise.
Reply
Old Nov 8, 2013 | 04:43 PM
  #2  
TedH's Avatar
TedH
Le Mans Master
Supporting Lifetime
25 Year Member
Liked
Loved
Community Favorite
 
Joined: Feb 1999
Posts: 8,351
Likes: 75
From: Tampa Bay FL
Default

Originally Posted by Mohamed
I have a cutting off problem when I fully kickdown my 72 C3, it cut off just some seconds after kicking down full accelerator. Is it due to carberator (fuel) or electrical issue? Please advise.
Is it a bog where the car sort of stumbles or does the car completely shut off? If shutting off, is it possible throttle linkage is interfering with wires leading to coil?

Could be anything from distributor/coil to carburetor. Did it just start happening? Any recent repairs/changes?
Reply
Old Nov 8, 2013 | 06:06 PM
  #3  
Mohamed's Avatar
Mohamed
Thread Starter
Intermediate
 
Joined: Feb 2013
Posts: 30
Likes: 0
Default

Yes, it is a stumbles.
It is just happening without doing any change or repair.
If it is due to distributor, what need to be replaced?
Reply
Old Nov 12, 2013 | 08:09 AM
  #4  
Danmf5's Avatar
Danmf5
Intermediate
 
Joined: Apr 2013
Posts: 31
Likes: 0
Default

My 78 did this it was two things. The distributor was part of the issue the advance was rusted shut, had to pry the weights open, ended up replacing the whole distributor with a msd. Also the carb needed rebuilt the fuel would not keep up, I replaced it with an efi system and the car woke up, you may just need an overhaul on the carb. Good luck!
Reply
Old Nov 12, 2013 | 08:18 AM
  #5  
TedH's Avatar
TedH
Le Mans Master
Supporting Lifetime
25 Year Member
Liked
Loved
Community Favorite
 
Joined: Feb 1999
Posts: 8,351
Likes: 75
From: Tampa Bay FL
Default

Originally Posted by Mohamed
Yes, it is a stumbles.
It is just happening without doing any change or repair.
If it is due to distributor, what need to be replaced?
If you decide to refresh both distributor and carb, Lars has the skills to bring both back to perfect condition. I recall he just worked on OEM distributors.

I wish I had rehabbed my OEM distributor. Could have saved some cash and gotten it set up by Lars in the process.
Reply
Old Nov 12, 2013 | 08:36 AM
  #6  
garygnu's Avatar
garygnu
Burning Brakes
 
Joined: Sep 2012
Posts: 818
Likes: 0
From: coon rapids mn
Default

maybe it mite be low float level ,or a bad accelerator pump.
Reply
Old Nov 12, 2013 | 09:04 AM
  #7  
Arny73's Avatar
Arny73
Instructor
 
Joined: Sep 2013
Posts: 153
Likes: 0
Default

Mine was doing the same thing a couple of weeks ago, it was the accelerator pump, it was stuck in the open and wasnt give the carb that little extra when I stomped on it.
Reply
Old Nov 12, 2013 | 09:14 AM
  #8  
TedH's Avatar
TedH
Le Mans Master
Supporting Lifetime
25 Year Member
Liked
Loved
Community Favorite
 
Joined: Feb 1999
Posts: 8,351
Likes: 75
From: Tampa Bay FL
Default

I agree with the other posts. Accelerator pump may be shot. Ethanol infused fuels are harder on the accelerator pump. Worth a try to replace accelerator pump. I think Lars sourced ethanol tolerant accelerator pump from NAPA when he rebuilt my carb. No issues since then.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-1

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-2

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
story-3

Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

 Joe Kucinski
story-4

Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

 Verdad Gallardo
story-5

Top 10 Corvettes Coming to Mecum Indy 2026!

 Brett Foote
story-6

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

 Michael S. Palmer
story-7

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

 Joe Kucinski
story-8

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

 Michael S. Palmer
story-9

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

 Joe Kucinski
Old Nov 12, 2013 | 12:00 PM
  #9  
billla's Avatar
billla
Le Mans Master
Supporting Lifetime
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
Default

My take on these issues is to get the timing right and remove that as a variable - and then begin troubleshooting the carb. Check the wires, timing and advance curve to ensure they're in the ballpark.

Is the trans auto or manual? What engine? Any modifications?
Reply
Old Nov 12, 2013 | 12:06 PM
  #10  
TimAT's Avatar
TimAT
Le Mans Master
15 Year Member
Liked
Loved
 
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Default

Go with the easy stuff first- fuel filter and ignition. KNOW where the ignition system is BEFORE you chase the carb.
Reply
Old Nov 12, 2013 | 12:28 PM
  #11  
Arny73's Avatar
Arny73
Instructor
 
Joined: Sep 2013
Posts: 153
Likes: 0
Default

It is a 4-speed with 454, carb was rebuild, new fuel tank and fuel lines. That's what I have done to it so far.
Reply
Old Nov 12, 2013 | 12:29 PM
  #12  
Arny73's Avatar
Arny73
Instructor
 
Joined: Sep 2013
Posts: 153
Likes: 0
Default

Sry I replied to the wrong thread
Reply
Old Nov 12, 2013 | 02:16 PM
  #13  
Cookie_M0nster's Avatar
Cookie_M0nster
Cruising
 
Joined: Nov 2013
Posts: 10
Likes: 0
From: Livermore CA
Default

Originally Posted by billla
My take on these issues is to get the timing right and remove that as a variable - and then begin troubleshooting the carb. Check the wires, timing and advance curve to ensure they're in the ballpark.

Is the trans auto or manual? What engine? Any modifications?
Originally Posted by TimAT
Go with the easy stuff first- fuel filter and ignition. KNOW where the ignition system is BEFORE you chase the carb.
This.

Before you start down the rabbit hole of carb stuff make sure the ignition system is exactly how it ought to be.

I had an issue similar to this in my '70 Chevelle. When I would stab it the engine would bog which led me to having to lift off or risk a stall. Turns out the weights in the Dist were stuck, as well as the HEI module were bad. When I fixed those the car ran a lot better but still wasn't just right. Since I knew the ignition was sound and fresh I chased after the old Carter AFB on top and adjusted the Accel Pump, and springs only to have the damned thing spring a leak one day coming home from school...the throttle plate shaft bushings disappeared and doused the whole intake, water pump, valve covers and dist in fuel. Now shes sporting a Holley 670 Street avenger and fires off at the touch of the key, and she will get em loose whenever I tell her too.

Last edited by Cookie_M0nster; Nov 12, 2013 at 02:17 PM. Reason: I accidentally a word
Reply
Old Nov 16, 2013 | 01:10 AM
  #14  
Mohamed's Avatar
Mohamed
Thread Starter
Intermediate
 
Joined: Feb 2013
Posts: 30
Likes: 0
Default

Guys, my C3 engine is 350 original without any modification and 400 Turbo 3 speed transmission, If I want to refresh the distributor/ignition, what parts need to be replaced?
Could the coil cause this problem?
Reply

Get notified of new replies

To C3 engine cutting off when fully kickdown





All times are GMT -4. The time now is 01:50 AM.

story-0
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-1
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-2
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE
story-3
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-4
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-5
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE
story-6
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-7
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-8
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-9
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