Last post on Jun 24, 2013 at 1:51 PM
You are in the Lexus RX 300/330/350
What is this discussion about?
Lexus RX 300, SUV
Oct 08, 2005 (1:13 pm)
I have some strange things going on with my 2001 Lexus RX-300. Before I visit lexus, I thought these problems must not be unique. The car sat, undriven for about 2 months, killing the battery. Not sure it is related, but about 100 miles afterward, the Check Engine, then TRAC, then VSC light just came on while driving. OBD II code 00174, "system too lean". I have the Lexus Factory Service Manual set, and the code describes a short-term/long term fuel trim problem. I can reset the code, and with increasing regularity it will reappear within 200 miles. With or without the code, there are times the motor seems to idle at about 1/2 speed, very smoothly but barely running while in gear, or stalling. As soon as I throttle up, the problem is gone, and reappears mostly after a trip under 10 miles.
I have checked all vaccuum and throttle body leak issues, to no avail. This machine is extrememly babied and well maintained, and I just passed 100k miles.
I own a mobile electronics chain, so I can return all kinds of databus, security, sound, or navigation interfacing information. Help please.
#8714 of 9498 Re: OBD II Code 00174 [sexilexi300]
Oct 09, 2005 (4:41 am)
I know you said you checked all vaccuum leak issues, but did you check the hose behind the air filter box directly under the brake fluid container? This one easily comes off the metal tube below it and is a common cause of CEL.
#8715 of 9498 Spider nest...
Oct 09, 2005 (6:59 am)
inside the idle air bypass module.
#8716 of 9498 Re: OBD II Code 00174 [mikey00]
Oct 09, 2005 (6:09 pm)
Yes, I saw a post discussing this already (might have been you) and checked it right away. Is the hose you describe not directly connected to the air cleaner?
#8717 of 9498 Re: OBD II Code 00174 [sexilexi300]
Oct 11, 2005 (3:08 am)
I think it is connected to the top. That's why when you lift up on the top to check the filter it pulls the hose off the metal tube below. I will double check when my wife comes home with the car tonight.
#8718 of 9498 Maintenance Issues on my 2000 RX300
Oct 12, 2005 (6:54 am)
My RX is at the dealer now waiting to be picked up. I took it in to check on the following 4 issues and the dealer is blowing them all off...
1) Q. When the key is in the ignition but not engaged there is a sizzling sound under the hood that is clearly heard on the driver side. A. They tell me it is a perfectly normal sound made by a solenoid blah, blah, blah and that most owners don't just stick the key in so they don't hear it. It literally sounds like something is frying under there. I see nothing posted here about this, has anyone else experienced it?
2) Q. Window washer fluid is leaking (I have the proof on the floor of my garage and on the two towels I placed there to collect it). A. Maintenance filled the reservoir and found no leaks anywhere in the line. WZUP with that, it's obviously leaking.
3) Q. Gas mileage seems to have decreased. A. They have no test for mileage...
4) Black streaks on my rims. A. Brake dust, but nothing wrong with the brakes.
I did find postings on this forum re Gas mileage and brake dust, but no answers (maybe you can give me a posting number on the answer to the mileage question) re brake dust, all I could find is how to remove it. Is the accumulation of brake dust just normal then?
I just can't imagine that all of this is "normal" and that I just have to live with it. Since I have a somewhat negative view of car dealers and mechanics, my instincts tell me that they're just blowing me off (until warranty expires maybe???). I want to be able to give them an informed response rather than just accepting what they tell me.
Thanks, in advance, for your input.
#8719 of 9498 Re: OBD II Code 00174 [sexilexi300]
Oct 12, 2005 (3:28 pm)
The hose is connected to the back of the air filter housing top. It makes a 90 degree turn directly under the brake fluid container and connects to a metal tube below. When the top of the air filter housing is opened, the hose can easily get disconnected from the metal tube which causes a check engine light. Don't confuse this with the hose connected to the side of the brake fluid container which also connects to a metal tube below.
#8720 of 9498 Re: Maintenance Issues on my 2000 RX300 [kmc4]
Oct 12, 2005 (4:05 pm)
1) The noise you describe when the key is inserted is normal.
2) This is not normal and may take some investagation by you before returning to the dealer. At what point of the car is it dripping from to the garage floor, how fast/slow, does it only leak when used or will it leak when just sitting, I would fill it to the fill line and monitor.
3) This is a tough one. What does "seems" to have decreased mean. You have a computer that displays MPG. Did it decrease or not? What type of driving do you do and what is your mpg. Do you have FWD or AWD? You may want to do a search and see what type of mileage others are getting or at least post yours. Mine is 19.7 for AWD on 80% rural country roads, 10% city, 10% highway.
4) The black streaks are most likely brake dust. The RX stock pads are quite good and have very little dusting but you do have to clean the wheels once in a while. Did you get the RX used? Did someone before you possibly do a brake job and use aftermarket pads that dust a little more? As long as the dealer checked the brakes I wouldn't worry about it. Just clean the wheels a little more often.
#8721 of 9498 Re: OBD II Code 00174 [mikey00]
Oct 14, 2005 (4:08 pm)
The hose is indeed connected properly. If anyone has advice before I begin diagnosing the A/F sensor, MAF, and VSC codes let me know. I will post my findings otherwise.
#8722 of 9498 Re: Maintenance Issues on my 2000 RX300 [mikey00]
Oct 14, 2005 (4:17 pm)
1) Normal noise. Mine is a kind of hum, and I can describe the active circuit from wiring diagrams if you would like.
2) A leak is a leak. It might be so slow they could not see it.
3) I get 21.9 with AMZOIL 10/30, and 24.7 with the new AMZOIL 0/30, 2WD with a little over 100k miles. I have some exotic 20" rims that add rotational wieght, but I adjust my mileage for the 5.49% tire circumference increase. I also drive like a little old lady, gentle enough that I am still on my original brake pads.
4) When I replace my brake pads, I will look for some ceramic pads which eliminate this problem.