Notices
RX - 1st Gen (1999-2003) Discussion topics related to the 1999 -2003 RX300 models

Check Engine Light Question

Thread Tools
 
Search this Thread
 
Old Apr 15, 2005 | 08:20 PM
  #1  
bizzy928's Avatar
bizzy928
Thread Starter
Lexus Champion
 
Joined: Feb 2002
Posts: 2,172
Likes: 0
From: Ontario
Default Check Engine Light Question

2000 RX300 AWD -- 109005km

Check engine light came on tonight. Before winter started we had some idle and stalling problems but they "stopped" after we replaced the battery. A few nights ago I was on an decline idling and the RPMs were fluctuating between 500-1000RPM, sounded like the engine wasn't able to breathe. I drove away to get the RPMs back up again. I don't know if that has anything to do with the CEL but every bit of info helps. There are no other noticable problems with the vehicle.

Does the CEL come on for regular scheduled maintanence intervals? Or does the CEL come on only when there is a problem?

My guess at this point would be an O2 Sensor.

Any input would be great!
Regards

Last edited by bizzy928; Apr 15, 2005 at 08:24 PM.
Reply
Old Apr 16, 2005 | 05:02 PM
  #2  
mikey00's Avatar
mikey00
Lexus Test Driver
 
Joined: Jul 2001
Posts: 959
Likes: 2
From: New Jersey
Default

The CEL only comes on for problems. May be just the idle air control valve needs cleaning. I think if you take it to the dealer they don't bother cleaning, just replace. If you have a Autozone around they will read the code for free. Then come back with the code and do a search both here and at Lexus owners club. You can get a good idea of what needs to be done.
Reply
Old Apr 17, 2005 | 07:36 PM
  #3  
bizzy928's Avatar
bizzy928
Thread Starter
Lexus Champion
 
Joined: Feb 2002
Posts: 2,172
Likes: 0
From: Ontario
Default

Update:

Dealer found a trouble code: P0171
Replaced the O2 Sensor at $221.40 for parts and charged 1 hour of labour. NOT covered under warranty.
Reply
Old Apr 18, 2005 | 05:15 PM
  #4  
VVT-i's Avatar
VVT-i
Lexus Champion
20 Year Member
Photogenic
Photoriffic
Shutterbug
 
Joined: May 2002
Posts: 2,781
Likes: 6
From: Georgia
Default

Originally Posted by bizzy928
Update:

Dealer found a trouble code: P0171
Replaced the O2 Sensor at $221.40 for parts and charged 1 hour of labour. NOT covered under warranty.
Wow, the P0171 System too lean is related to the Air flow meter on top of the air filter housing, not the O2. If the CEL come back, you tell your dealer please look at Short and Long term fuel trim in the data menu on the scan tool.
Reply
Old Apr 19, 2005 | 09:51 AM
  #5  
VSsc400's Avatar
VSsc400
Lexus Fanatic
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (1)
 
Joined: Apr 2002
Posts: 5,479
Likes: 2
From: IL
Default

that's actually not an o2 sensor. It's a Air flow sensor. Looks like an O2 sensor but it isn't.
Reply
Old Apr 27, 2005 | 12:33 PM
  #6  
chicagoblknazn's Avatar
chicagoblknazn
Lead Lap
20 Year Member
Photogenic
Liked
Loved
 
Joined: Oct 2001
Posts: 3,723
Likes: 4
From: Illinois
Default

Originally Posted by VSsc400
that's actually not an o2 sensor. It's a Air flow sensor. Looks like an O2 sensor but it isn't.
Same code was just triggered in my car yesterday. Took it to AZ and they told me P0171 and P0174.
Reply
Old Apr 27, 2005 | 01:00 PM
  #7  
Lexmex's Avatar
Lexmex
CL Community Team
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Apr 2004
Posts: 17,329
Likes: 210
From: Miami, Florida
Default

I am 7,700 feet with about 25% less oxygen than at sea level. Whenever I get a check engine light down here, I always place a bet with my mechanic that it is a P0171. We get out the OBDII scanner, and I am always right. One time it was K&N gunk on the MAF, but occasionally I get a low idle in certain parts of the year or under certain conditions, i.e., after a 3,000 foot drop I sometimes get vapor lock.

The new mods I have with regard to greater air flow help incredibly, especially when going up hills, but at sea level I would be just fine.

Usually, there are other codes that would indicate which bank of O2 sensors had a problem, but I have never been affected by that.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
xmssc300
SC - 1st Gen (1992-2000)
1
Dec 13, 2012 09:57 AM
OnyxGS300
GS - 1st Gen (1993-1997)
11
Nov 10, 2007 07:49 AM
Meetya
RX - 1st Gen (1999-2003)
2
Jun 24, 2007 04:10 AM
Megatron
ES - 1st to 6th Gen (1990-2018)
9
Jun 22, 2005 09:46 PM
richma7175
ES - 1st to 6th Gen (1990-2018)
7
Aug 10, 2003 07:54 PM




All times are GMT -7. The time now is 10:18 AM.

story-0
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-1
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-2
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-3
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-4
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-5
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-6
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
story-7
GX 550 vs TX 550: Best 3-Row Luxury Lexus Family Hauler

Slideshow: comparing the pricings, specs, power, fuel economy, fun-factor, and features of the GX 550 Luxury+ and TX 550h+ Luxury.

By Michael S. Palmer | 2026-03-19 13:44:11


VIEW MORE
story-8
9 Best Lexus Models You Can Buy for Half Price (And 1 You Shouldn't!)

Slideshow: 9 best Lexus models you can buy for half price and 1 you should avoid

By Joe Kucinski | 2026-03-19 12:01:07


VIEW MORE
story-9
2026 Lexus NX Buyer's Guide: Models, Features, Prices & More!

Here's everything you need to know about the latest NX.

By Brett Foote | 2026-03-19 11:56:59


VIEW MORE