Notices
LS - 3rd Gen (2001-2006) Discussion topics related to the flagship Lexus LS430

Help with code P0300

Thread Tools
 
Search this Thread
 
Old Oct 8, 2015 | 10:30 AM
  #1  
honasbone's Avatar
honasbone
Thread Starter
Driver
 
Joined: Mar 2014
Posts: 102
Likes: 0
From: WA
Default Help with code P0300

I started the car yesterday morning and noticed it idling a little rough. Nothing significant. But not it's usual self. Pulled away from the house and the problem was gone. Started up this morning and got the same rough idle. Then the CEL and VSC fun times popped up. Plugged in the techstream and saw P0300 as the one and only code.

Seems the rough idle is only present when the engine is cold. Can't say that with 100% certainty. Just what my butt tells me during the driving experience to and from work.

Any ideas on what this is? Looking online I see others (non LS owners) saying it may have something to do with a misfire. I'm not sure where to find out in techstream which (if any) cylinders may have had a misfire though. Can I locate that in techstream? Or is this possibly something else?

Appreciate any help on this.

Last edited by honasbone; Oct 8, 2015 at 01:06 PM.
Reply
Old Oct 8, 2015 | 04:35 PM
  #2  
rkw77080's Avatar
rkw77080
Pole Position
15 Year Member
Photogenic
Photoriffic
Liked
 
Joined: Mar 2011
Posts: 2,188
Likes: 729
From: Texas
Default

Here are pages from the 2001-2003 repair manual about P0300...
Attached Files
File Type: pdf
P0300.pdf (93.8 KB, 1953 views)

Last edited by rkw77080; Oct 8, 2015 at 04:39 PM.
Reply
Old Oct 8, 2015 | 05:17 PM
  #3  
honasbone's Avatar
honasbone
Thread Starter
Driver
 
Joined: Mar 2014
Posts: 102
Likes: 0
From: WA
Default

Nice. Thanks a ton. That's quite the list of stuff to check. Can you recommend a scan tool? Preferably something that doesn't break the bank
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
MuGGzyx
SC - 1st Gen (1992-2000)
5
Jul 2, 2025 01:29 PM
Markers
SC - 1st Gen (1992-2000)
1
May 1, 2016 07:58 PM
GeeEss4
GS - 2nd Gen (1998-2005)
1
Dec 16, 2012 06:40 PM
DriverT
LS - 1st and 2nd Gen (1990-2000)
3
May 6, 2011 11:31 AM




All times are GMT -7. The time now is 09:13 AM.

story-0
2026 Lexus ES Review: Lexus Re-Embraces Founding Principles

Slideshow: Our First-Drive Review of the 2026 Lexus ES!

By Michael S. Palmer | 2026-05-29 20:30:16


VIEW MORE
story-1
10 Lexus Bargains That are Cheaper Than a New Toyota RAV4

Slideshow: 10 Lexus bargain that are cheaper than a new Toyota.

By Joe Kucinski | 2026-05-20 10:28:20


VIEW MORE
story-2
8 Weirdest Things Lexus Has Ever Built

Slideshow: From hoverboards to luxury yachts, these are the strangest projects Lexus has ever attached its badge to.

By Verdad Gallardo | 2026-05-16 11:34:36


VIEW MORE
story-3
10 Lexus Designs That Have Aged Like Fine Wine

Slideshow: Some luxury cars chase trends, but these Lexus models look better now than they did when they first rolled into showrooms.

By Verdad Gallardo | 2026-05-06 17:58:29


VIEW MORE
story-4
8 Tips for Improving Your Hybrid or Plug-in Hybrid's Efficiency!

Slideshow: How to Get the Best Fuel Economy with a Hybrid and Plug-In Hybrid!

By Michael S. Palmer | 2026-05-05 20:54:44


VIEW MORE
story-5
10 Best Lexus Models No One Remembers

Slideshow: 10 best Lexus models no one remembers.

By Joe Kucinski | 2026-05-05 17:33:28


VIEW MORE
story-6
TRD Off-Road Premium: Best 2026 4Runner, Except This One Thing

Slideshow: diving into 4Runner TRD Off-Road Premium's pricing, performance, fuel economy, features, and amenities!

By Michael S. Palmer | 2026-04-23 13:09:18


VIEW MORE
story-7
Top 10 Lexus & Toyotas to Drive Before You Die!

Slideshow: the 10 Lexus and Toyota vehicles you need to drive before you die.

By Joe Kucinski | 2026-04-23 10:34:24


VIEW MORE
story-8
Top 10 Lexus/Toyotas With The LEAST 5-Year Depreciation

Slideshow: Top 10 Lexus/Toyota models with the lowest 5-year depreciation rate.

By Joe Kucinski | 2026-04-08 12:19:06


VIEW MORE
story-9
Lexus LC500 Convertible Auction: A Preview of Rising Values?

The LC hasn't even disappeared from the Lexus lineup yet, and we're already seeing signs of an explosive market.

By Brett Foote | 2026-04-06 09:25:02


VIEW MORE