PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

LS6 engine stalling issues

Thread Tools
 
Search this Thread
 
Old Mar 15, 2021 | 12:13 AM
  #1  
72Z/28's Avatar
Thread Starter
Staging Lane
15 Year Member
 
Joined: Sep 2006
Posts: 51
Likes: 3
Default LS6 engine stalling issues

Hi
I have got 68 camaro with LS6 engine. I have been having stalling issues or even the engine dies when taking my foot off the gas pedal and press the clutch and brake to slow down at the stop light or sometimes stalls when at complete stop. This happens with and without the A/C on. Other times when coming to a stop light, the engine wants to stall but the rpm picks up again.

the car has a cam but not sure about the specs as it was there when I bought the car.

it also has FAST 92mm intake.

did the dyno tuning a few years ago but not street tuning.

last month, I had to retune the PCM after installing LS3/LS7 style MAF sensor and did the dyno tuning as well and lowered the rpm from 800 to 750RPM

I test drove the car, and noticed the stalling was worse and was coming more frequently.

The changes I made afterwards hoping to address this was the following:

-Replaced the stock throttle body with FAST 92mm to match the FAST 92mm intake manifold

- Replaced IAC,TPS,MAP sensors with new ones.

-Replaced the oil cap breather with OEM type oil cap and connected fresh air hose from the throttle body to passenger side valve cover.

The above mods helped a bit with stalling issues mentioned above but the problem did not go away completely. Also, after a long drive, noticed fuel pressure dropped a bit to around 46psi from 50psi (pressure gauge at Aeromotive fuel pressure regulator with vacuum reference connected from Intake manifold)

Honestly, I am not sure what else to look for or the car has to be street tuned to pin point exactly what the issue is

will appreciate your input guys



Last edited by 72Z/28; Mar 15, 2021 at 10:28 AM.
Reply
Old Mar 15, 2021 | 05:34 AM
  #2  
Darth_V8r's Avatar
Moderator
10 Year Member
Liked
Loved
Community Favorite
iTrader: (4)
 
Joined: Jul 2014
Posts: 10,451
Likes: 1,873
From: My own internal universe
Default

Moved to PCM section. Will get more looks over here.
Reply
Old Mar 15, 2021 | 09:46 AM
  #3  
72Z/28's Avatar
Thread Starter
Staging Lane
15 Year Member
 
Joined: Sep 2006
Posts: 51
Likes: 3
Default

Originally Posted by Darth_V8r
Moved to PCM section. Will get more looks over here.
Thanks
Reply
Old Mar 16, 2021 | 05:03 AM
  #4  
72Z/28's Avatar
Thread Starter
Staging Lane
15 Year Member
 
Joined: Sep 2006
Posts: 51
Likes: 3
Default

Anybody willing to help?
Reply
Old Mar 16, 2021 | 06:53 AM
  #5  
Bogan Edition Z28's Avatar
On The Tree
 
Joined: Dec 2020
Posts: 105
Likes: 26
From: Chesapeake Bay
Default

I had similar issues. More of an idle hang after a tune. I "disabled" throttle cracker and all is good.
Reply
Old Mar 16, 2021 | 01:05 PM
  #6  
72Z/28's Avatar
Thread Starter
Staging Lane
15 Year Member
 
Joined: Sep 2006
Posts: 51
Likes: 3
Default

Originally Posted by Bogan Edition Z28
I had similar issues. More of an idle hang after a tune. I "disabled" throttle cracker and all is good.
Thanks, I do not have Idle hanging issues. The issue is the engine dies when letting my foot off the gas pedal and slowing down to come to a stop. It also happens the moment I turn the steering while reaching to a complete stop
Reply
Old Mar 16, 2021 | 02:31 PM
  #7  
cam's Avatar
cam
TECH Junkie
iTrader: (9)
 
Joined: Apr 2004
Posts: 3,389
Likes: 67
From: in the garage
Default

Check for vacuum leak. Looked for cracked PCV hose etc
Reply
Old Mar 16, 2021 | 11:08 PM
  #8  
72Z/28's Avatar
Thread Starter
Staging Lane
15 Year Member
 
Joined: Sep 2006
Posts: 51
Likes: 3
Default

Originally Posted by cam
Check for vacuum leak. Looked for cracked PCV hose etc
I have LS6 valley cover with built in PCV. There is a cross over hose (U shaped hose) between the valley cover nipple going to intake manifold. However, I did notice some yellowish stains/leakage between upper and lower parts of FAST intake manifold. The same stains noticed also between the intake and heads. Most likely the stupid rope seal & gaskets are bad which cause vacuum leak.

Anyways, went ahead and ordered new seals. Hopefully this will address the stalling issues




Last edited by 72Z/28; Mar 17, 2021 at 01:56 AM.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

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

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo




All times are GMT -5. The time now is 02:46 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
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-3
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-4
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-5
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-6
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-7
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-8
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-9
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