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: 28
Likes: 0
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: 28
Likes: 0
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: 6,639
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 11:45 AM.

story-0
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-1
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-2
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-3
2027 Corvette vs The World: Every C8 vs Its Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-24 16:12:42


VIEW MORE
story-4
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE
story-5
5 MOST and 5 LEAST Popular Corvette Model Years in History!

Slideshow: 5 most and least popular Corvette model years.

By Joe Kucinski | 2026-04-08 13:25:01


VIEW MORE
story-6
2027 Corvette Buyer's Guide: Everything You Need to Know!

Slideshow: 2027 Corvette buyer's guide

By Joe Kucinski | 2026-04-17 16:41:08


VIEW MORE
story-7
10 Things C8 Corvette Owners Hate (But Won't Tell You)

Slideshow: 10 things C8 Corvette owners hate, but won't tell you.

By Joe Kucinski | 2026-04-01 18:36:07


VIEW MORE
story-8
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!

Slideshow: Should you add one of these incredible Corvettes to your garage?

By Brett Foote | 2026-04-01 18:14:05


VIEW MORE
story-9
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)

Slideshow: Every Corvette Grand Sport explained

By Joe Kucinski | 2026-03-26 07:13:44


VIEW MORE