C6 Tech/Performance LS2, LS3, LS7, LS9 Corvette Technical Info, Internal Engine, External Engine, Tech Topics, Basic Tech, Maintenance, How to Remove & Replace
Sponsored by:
Sponsored by:

PO300 Code

Thread Tools
 
Search this Thread
 
Old Mar 12, 2021 | 06:38 PM
  #1  
Bryan250's Avatar
Bryan250
Thread Starter
Intermediate
 
Joined: Oct 2020
Posts: 43
Likes: 7
From: Bakersfield CA
Default PO300 Code

I believe it may be the Torque Tube causing the issue.

Getting a PO300 code. The car is idling very rough.

I have checked the Spark Plugs, Coils, and Valve Springs.

The car runs fine and can go for a while without getting the code. But if i let it idle for mare than 5 mins or so it will start to run rough and throw the code.

I just recently put a 3400 stall into it and did it with out removing the TT I believe the tweaking on the TT may have blown that rubber bushing. But not sure if that could cause the engine to run rough.

Just for reference the car also has and AA kit, Catch Can, LT Headers with not cats....

Thoughts?
Reply
Old Mar 12, 2021 | 09:14 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: 15,621
Likes: 4,069
From: Cape Coral, Florida
Default

For the average DIY’er without the right equipment (scope, scan tool) misfires will only involve swapping or changing parts and this can get expensive !!...you forgot injectors and you can usually tell if it’s ignition or injectors by looking at the fuel trims. A scan tool can also determine which cylinder or cylinders are misfiring.

Last edited by C5 Diag; Mar 12, 2021 at 09:16 PM.
Reply




All times are GMT -4. The time now is 12:26 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