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

OT: Engine Code PO306

Thread Tools
 
Search this Thread
 
Old Jan 27, 2007 | 11:24 AM
  #1  
desi's Avatar
desi
Thread Starter
Melting Slicks
 
Joined: Sep 2002
Posts: 2,783
Likes: 2
From: Engineers do it better.
Default OT: Engine Code PO306

My daily driver, 98 V6 Camaro 5 spd, started to run weird yesterday. It idles fine, run ok under very light acceleration, but is really rough under normal/heavy acceleration.

The engine code is PO306, which is "detected misfire in cylinder 6". What could be the cause for this code? I just bought the car 3 months ago and had been running great until all of a sudden.

I filled up at the gas station a couple of day ago with 87 fuel. Within 5 minutes the car started to run rough. I alway put 89, but this time for some reason I used 87. Later on, I put in Lucas Octane booster thinking maybe it was fuel related. But nothing changed.

What could be possible causes for this code? Spark plugs? Wires? Ignition Module??

I was going to post over on the C4 or C5 side, but I think there's a lot of knowledge on the C3 too
Reply
Old Jan 27, 2007 | 12:04 PM
  #2  
voat's Avatar
voat
Intermediate
20 Year Member
 
Joined: May 2005
Posts: 39
Likes: 2
From: Bay Point, CA
Default

I use to own a 1997 V6 Camaro (I own a 2001 V6 Camaro now, great car with good gas mileage) and there was a problem with the factory plug wires. Just replace the number 6 to see if it helps. They are a bear to change.
Reply
Old Jan 27, 2007 | 01:50 PM
  #3  
desi's Avatar
desi
Thread Starter
Melting Slicks
 
Joined: Sep 2002
Posts: 2,783
Likes: 2
From: Engineers do it better.
Default

Do the plugs/wires have to be changed from under the car? It doesn't look like there's enough room from the top.

In summer, I changed the wires and plugs on my Montana. It took 6 freaking hours. You have to remove motor mounts and tilt engine forward to get to the rear ones... what a PITA.

With this weather, if it's a long job I am thinking it might be better to take it to a mechanic.
Reply
Old Jan 28, 2007 | 11:33 AM
  #4  
voat's Avatar
voat
Intermediate
20 Year Member
 
Joined: May 2005
Posts: 39
Likes: 2
From: Bay Point, CA
Default

I replaced the wires several years ago but from what I remember it was not as hard as your Montana, I did not have to remove the mounts or tilt the engine but I do remember having to get to some from underneath and it did take a few hours, but not six.
Reply
Old Jan 28, 2007 | 11:54 AM
  #5  
Duke94's Avatar
Duke94
Le Mans Master
25 Year Member
Liked
Loved
Community Favorite
 
Joined: Mar 2001
Posts: 6,640
Likes: 287
From: Ann Arbor Michigan
Default

Not sure if you have the same problem, but I had a 94' Camaro with V8 and 6 speed. Idled great, ran good at low easy going RPM. It would misfire during hard acceleration. Spent many hours trying to figure it out. Even took it to a couple of "experts". After playing with it all summer, I noticed that the plug wires on one side were wrapped around each other. I straightened them out and got the wires back where they should be and no more miss. From what I have been told, the ignition system has MUCH power and will fire the ajoining plug if the wires are not routed correctly. It gave me the misfire code also. I agree with voat, replace the wires. On my Z28, only way was from below.
Reply

Get notified of new replies

To OT: Engine Code PO306





All times are GMT -4. The time now is 09:43 PM.

story-0
5 Best & 5 Most Overrated Corvette Track Packages of All Time!

Slideshow: The 5 best and 5 most overrated Corvette track packages ever.

By Joe Kucinski | 2026-06-09 12:46:45


VIEW MORE
story-1
Every 2027 Corvette Engine Explained

Slideshow: Every 2027 Corvette engine explained

By Joe Kucinski | 2026-06-09 12:16:31


VIEW MORE
story-2
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette

Slideshow: A Jaguar designer's personal project imagines what a modern front-engined Corvette might look like if Chevrolet revisited the golden age of the Stingray.

By Verdad Gallardo | 2026-06-08 19:53:43


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