C5 Tech Corvette Tech/Performance: LS1 Corvette Technical Info, Internal Engine, External Engine, Tech Topics, Basic Tech, Maintenance, How to Remove & Replace
Sponsored by:
Sponsored by:

rough idle after deceleration

Thread Tools
 
Search this Thread
 
Old Apr 21, 2019 | 07:00 PM
  #1  
surfer02000's Avatar
surfer02000
Thread Starter
Advanced
10 Year Member
 
Joined: Dec 2012
Posts: 53
Likes: 0
From: New Caney Texas
Default rough idle after deceleration

Before I take it to a shop. I was hoping someone had some insight. I went through the replace special(plugs, Wires, Coil Packs, Fuel Pressure regulator, Checked the fuel pressure, cleaned throttle body and MAF and sprayed fluid around vacuum hoses for leaks.

On initial start up everything is fine at idle and good while pressing the accelerator pedal. The problem starts as rpm's drop it then feels like it is running on 7 cylinders. Once I let it idle for about 10 seconds it gets smooth and I can press accelerator again .

Last edited by surfer02000; Apr 21, 2019 at 07:01 PM.
Reply
Old Apr 21, 2019 | 11:36 PM
  #2  
C5 Diag's Avatar
C5 Diag
Moderator, Tech Contributor
Supporting Lifetime Gold
10 Year Member
Veteran: Air Force
Liked
Community Favorite
 
Joined: Sep 2013
Posts: 15,598
Likes: 4,057
From: Cape Coral, Florida
Default

With the issues you are experiencing it’s difficult to diagnose your car just based on your symptoms !!...I’m sure the shop you are taking it to has all the right diagnostics equipment...could be many things !!
Reply
Old Apr 23, 2019 | 12:46 PM
  #3  
C5 Diag's Avatar
C5 Diag
Moderator, Tech Contributor
Supporting Lifetime Gold
10 Year Member
Veteran: Air Force
Liked
Community Favorite
 
Joined: Sep 2013
Posts: 15,598
Likes: 4,057
From: Cape Coral, Florida
Default

Originally Posted by surfer02000
Before I take it to a shop. I was hoping someone had some insight. I went through the replace special(plugs, Wires, Coil Packs, Fuel Pressure regulator, Checked the fuel pressure, cleaned throttle body and MAF and sprayed fluid around vacuum hoses for leaks.

On initial start up everything is fine at idle and good while pressing the accelerator pedal. The problem starts as rpm's drop it then feels like it is running on 7 cylinders. Once I let it idle for about 10 seconds it gets smooth and I can press accelerator again .
Does the drop in RPM happen during a "rapid" deceleration from high RPM or just a gradual decrease ??....could possibly be TPS or MAP sensor issues !!
Reply
Old Apr 23, 2019 | 05:44 PM
  #4  
surfer02000's Avatar
surfer02000
Thread Starter
Advanced
10 Year Member
 
Joined: Dec 2012
Posts: 53
Likes: 0
From: New Caney Texas
Default

appreciate the replies. Seems to happen whenever I press the gas pedal, smooth going up rough coming down(gradual decrease). And then it stays rough unless I let it sit for I'm guessing around 10 seconds.

Last edited by surfer02000; Apr 23, 2019 at 05:49 PM.
Reply
Old Apr 23, 2019 | 06:07 PM
  #5  
C5 Diag's Avatar
C5 Diag
Moderator, Tech Contributor
Supporting Lifetime Gold
10 Year Member
Veteran: Air Force
Liked
Community Favorite
 
Joined: Sep 2013
Posts: 15,598
Likes: 4,057
From: Cape Coral, Florida
Default

Originally Posted by surfer02000
appreciate the replies. Seems to happen whenever I press the gas pedal, smooth going up rough coming down(gradual decrease). And then it stays rough unless I let it sit for I'm guessing around 10 seconds.
Like I had mentioned we would only be guessing on a diagnosis...hope the shop you take it to aren't just "wrench turners"....if they don't use a scan tool AND a scope it may get expensive !!...good luck and let us know what they find !!
Reply
Old Apr 23, 2019 | 06:16 PM
  #6  
surfer02000's Avatar
surfer02000
Thread Starter
Advanced
10 Year Member
 
Joined: Dec 2012
Posts: 53
Likes: 0
From: New Caney Texas
Default

I'm going to let one of the corvette specialty shops around the Houston area take a look at it. Just seems to be an odd issue for me to figure out, but hoping its something simple for a knowledgeable shop, Thx
Reply

Get notified of new replies

To rough idle after deceleration





All times are GMT -4. The time now is 03:06 PM.

story-0
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-1
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-2
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-3
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-4
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-5
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-6
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-7
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-8
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-9
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