Generation III External Engine LS1 | LS6 | Bolt-Ons | Intakes | Exhaust | Ignition | Accessories
Sponsored by:
Sponsored by:

car stumbling while underload

Thread Tools
 
Search this Thread
 
Old Dec 29, 2010 | 06:38 AM
  #1  
97lt1z28's Avatar
Thread Starter
Launching!
iTrader: (1)
 
Joined: Dec 2005
Posts: 204
Likes: 0
From: PA
Default car stumbling while underload

Hey guys,
I woke up this morning to drive to work and had a issue with my 98 ls1 camaro. car s stock with basic bolt ons such as headers a slp lid and kandN filter. so anyway...the car was stumbling from the begining in first gear. literally the car started shaking. i turned it off put it into neutral and strated it. It fired right back up no prob. I threw it few quick revs and it acted fine. normal oil pressure, charging and everything else. so i continue to drive thinking it was a hick up. i get on the high way and shift it to 4th and it stumbles around 2300 rpm and then picks back up fine. driving in 6th gear now at around 1900 rmp and give it a little throttle and same thing happen so i shift in to 5 th and sitting around 2800 rpm no stumble....go to get it and there it goes again.
Just asking for ideas...my thoughts where possible bad gas (i use 91) or injector and or bad plugs maybe. There any no check engine lights on on other that this stumle the car runs fine. By the way it only had 44K on the motor and tranny with a new (stock) clutch and throw out bearing. Thanks guys
Reply
Old Dec 29, 2010 | 07:34 AM
  #2  
97lt1z28's Avatar
Thread Starter
Launching!
iTrader: (1)
 
Joined: Dec 2005
Posts: 204
Likes: 0
From: PA
Default

i did some research and am going to
clean my MAF
change fuel filter
use some fuel system cleaner
and check my fuel pressure
as these seem to be the most common issues
Any other thoghts....again whats weired is that there are no codes which to me knocks out the MAF and failing fuel pump and vacum leak
Reply
Old Dec 29, 2010 | 10:10 AM
  #3  
thunderstruck507's Avatar
11 Second Club
iTrader: (18)
 
Joined: Mar 2008
Posts: 8,358
Likes: 27
From: Northwest AR
Default

Inspect your plug wires, could be cracked and arcing on a header tube
Reply
Old Dec 29, 2010 | 10:29 AM
  #4  
98ws6blk's Avatar
TECH Apprentice
15 Year Member
 
Joined: Jul 2010
Posts: 363
Likes: 1
From: Huntsville, AL
Default

Sounds electrical to me...check plugs/wires like said above.
Reply
Old Dec 29, 2010 | 11:20 AM
  #5  
djfury05's Avatar
10 Second Club
15 Year Member
iTrader: (30)
 
Joined: Jan 2008
Posts: 3,428
Likes: 4
From: Beaufort, SC
Default

Check all your grounds.. it wouldn't hurt to pull each one off and sand the bottom of it a little bit and then tighten back down
Reply
Old Mar 20, 2011 | 04:29 PM
  #6  
revtech101's Avatar
Staging Lane
 
Joined: Mar 2011
Posts: 77
Likes: 0
From: Newark, CA
Default

Originally Posted by thunderstruck507
Inspect your plug wires, could be cracked and arcing on a header tube

The thing is, the car only hesitates at very low rpms such as less than 2000rpm. This is when the car is under load. After that, the car picks up speed with no issues regardless of load.

I do not think it is the MAF, Spark plugs or plug wires. Otherwise the problem would be transparent at all rpms.
Reply
Old Mar 20, 2011 | 09:38 PM
  #7  
sabersaw30's Avatar
11 Second Club
iTrader: (10)
 
Joined: Mar 2006
Posts: 536
Likes: 0
From: Hilliard fl.
Default

Have you took the screen out of the maf?I took mine out know my car stutters at cruising speeds.I got to get my car retuned without the screen.
Reply
Old Mar 20, 2011 | 09:40 PM
  #8  
bayer-z28's Avatar
TECH Veteran
20 Year Member
iTrader: (14)
 
Joined: Apr 2005
Posts: 4,085
Likes: 1
From: N. Falmouth MA
Default

Breaking up on load is typically an ignition issue. I'd do plugs and wires. Cheap and easy first. Change your fuel filter while you're at it too. That can act the same way.


Originally Posted by revtech101
The thing is, the car only hesitates at very low rpms such as less than 2000rpm. This is when the car is under load. After that, the car picks up speed with no issues regardless of load.

I do not think it is the MAF, Spark plugs or plug wires. Otherwise the problem would be transparent at all rpms.
There's more of a load on the ignition system during lower RPMs. It's a text book way to check for ignition problems; "bog" it. More of a load ESPECIALLY in a higher gear and low R's.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

 Brett Foote
story-1

Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

 Pouria Savadkouei
story-2

Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

 Verdad Gallardo
story-3

7 Most Reliable High-Performance Engines GM Has Ever Built

 Verdad Gallardo
story-4

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

 Verdad Gallardo
story-5

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

 Pouria Savadkouei
story-6

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

 Verdad Gallardo
story-7

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-8

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-9

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
Old Mar 21, 2011 | 10:59 PM
  #9  
revtech101's Avatar
Staging Lane
 
Joined: Mar 2011
Posts: 77
Likes: 0
From: Newark, CA
Default

Originally Posted by bayer-z28
Breaking up on load is typically an ignition issue. I'd do plugs and wires. Cheap and easy first. Change your fuel filter while you're at it too. That can act the same way.



There's more of a load on the ignition system during lower RPMs. It's a text book way to check for ignition problems; "bog" it. More of a load ESPECIALLY in a higher gear and low R's.
Any specific plugs you recommend?

Last edited by revtech101; Mar 23, 2011 at 06:39 PM.
Reply
Old Apr 24, 2011 | 08:30 PM
  #10  
nitroracer's Avatar
Staging Lane
15 Year Member
iTrader: (4)
 
Joined: Apr 2009
Posts: 59
Likes: 1
From: Erie/Nottingham, Pa
Default

Originally Posted by 97lt1z28
Hey guys,
I woke up this morning to drive to work and had a issue with my 98 ls1 camaro. car s stock with basic bolt ons such as headers a slp lid and kandN filter. so anyway...the car was stumbling from the begining in first gear. literally the car started shaking. i turned it off put it into neutral and strated it. It fired right back up no prob. I threw it few quick revs and it acted fine. normal oil pressure, charging and everything else. so i continue to drive thinking it was a hick up. i get on the high way and shift it to 4th and it stumbles around 2300 rpm and then picks back up fine. driving in 6th gear now at around 1900 rmp and give it a little throttle and same thing happen so i shift in to 5 th and sitting around 2800 rpm no stumble....go to get it and there it goes again.
Just asking for ideas...my thoughts where possible bad gas (i use 91) or injector and or bad plugs maybe. There any no check engine lights on on other that this stumle the car runs fine. By the way it only had 44K on the motor and tranny with a new (stock) clutch and throw out bearing. Thanks guys
My 98' starting having nearly the exact same issue in the middle of last week. Didn't have a chance to look the car over until the weekend, but something obviously wasn't right and it never set a check engine light.

Ended up being one of my spark plug wires was sitting on the plug but not pressed on all the way. They are the original gm wires with 95k so I can see how that many heat cycles would loosen one up a bit.
Reply




All times are GMT -5. The time now is 12:25 AM.

story-0
6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

Don't get dad new socks or a grill brush this year.

By Brett Foote | 2026-06-09 14:55:56


VIEW MORE
story-1
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-05-28 11:05:11


VIEW MORE
story-2
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-3
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


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