Hello everybody,
An interesting issue came up this Sunday evening on our 2002 AWD RX300. We were driving up an extremely steep hill (those who have driven in Sausalito, CA can relate) when the RX stalled. So I put the vehicle in Park, and start it up again. Starts without a problem. Put it in Drive and notice that the "check engine" and the VSC lights are on.
As soon as I could, I called Lexus Roadside and the helpful guy on the phone recommended that if the vehicle drives fine without any issues (shuddering, stalls etc.), I should be safe to drive it home (50 miles), but should take it to the dealer ASAP.
At that point, the RX is driving well without any problems. But both the lights are still on. Figured I'll call the dealer first thing Monday. Then at some point later, the lights are off. During all this time, the RX is still driving like buttah

So my questions to the esteemed members are:
a. What should I make of this?
b. Should I still call the dealer?
c. Has this happened to anybody before?

Thanks in advance,
-chatrathi

 

This hasn't happened to me, but I would definitely bring it in and have them check what happened. They will be able to get the info from the computer and find out what caused the lights to go on. Could be minor, could be major or it could be nothing. Better to be safe than sorry IMO.

JP

 

I will be taking the RX in on Thursday to have it checked out. Will keep you posted on what I find out!

-chatrathi

 

chatrathi

What you described never happened to me. But if it did, here is what I would think and do about it:

1. Would try not to top up the gas tank. It may be related to lack of fuel pickup from the fuel pump (low gas level, dirty gas, dirty fuel filter, etc).
2. Would not try to top up the transmission fluid, where a low level in the steep incline could have affected the transmission, at that time!
3. Would not try to top up engine oil, where low level could have starved the engine of oil during the steep incline.
4. Do not disconnect the battery or reset the ECM because the Lexus tech won't be able to read the error codes. Whenever they read the codes, it would be interesting if you could let us know what they are?!?!?

Other than that, I don't think that water pump cavitation could have resulted in stalling the engine. I am trying to think what could have affected the vehicle so much while running on an angle. It must be related to a fluid (or lack of)!

When I was in the NAVY, testing new gear always included what was called "inclination trials" to ensure every aspect of new equipment could keep running even in exceptionally rough seas. To do so, we would put the ship at ridiculous angles! Sounds like something exceptional happened to you!

Please keep us posted. Good luck.

JB

 

J.B.:
Thanks for the detailed reply. The one thing that I have already done that departs from your recommendation (oops!) is that I had to fill the tank. We were 50 miles away from home, so I didn't want to risk it

However one more thing that did happen was, as I was driving up the street (the damn incline probably was almost 35-40 deg!!). I stopped to briefly read the Street signs, then when I accelerated to move up, for about a foot or so, the vehicle slipped back (while it was in D). I believe that at that point, the vehicle stalled. And the lights (Check Engine and VSC) came on and stayed on for about a couple of hours.

Anyway, more details as soon as I get back from the dealer.

-chatrathi

 

So the dealer checked the codes in the computer. They feel that there is a problem with the emissions control module or vacuum something or the other (more details when I see the work order).

They will need to keep my baby overnight and order a part in. Not what I wanted to hear, but if it's best for the RX then it's OK by me

THey put me in a loaner RX330 (which is sweet - a detailed posting on my observations a little bit later). Service Manager also assured me that it will all be covered under warranty.

So more details when I pick up the car tomorrow.

-chatrathi

 

Picked up the RX today. The issue was logged as a faulty "Air Flow Control Sensor". It was replaced under warranty.

The usual extra special Lexus service courtsey was doled out in heaping helpings!

-chatrathi

 

Mant Thanks for the info. It realy helps to finnaly understand what was found after thinking about this for a while like many of us have.. Thanks again!

 

The only problem I have had with warning lights was apparently a loose gas cap.. The warning engine light came on, when I called the 800# from the road Lexus said to check the cap, which seemed tight, but I removed and reclosed it and the light was out. Will never know what really happened.

 

parula:
That's exactly one of the things that the Lexus Roadsite assistance asked me to check! Of course given that the final root cause was something different, my attempts to do the same didn't make a difference.

Can the more mechanically blessed amongst us, give an explanation of how a loose gas cap could affect the systems that can potentially trigger the "Check Engine Light"?

-chatrathi

 

chatrathi,

From the RX330 Owners Manual, P78:

(h) Malfunction Indicator Lamp
This lamp comes on when the ignition key is turned to the
“ON” position and goes off after the engine starts. This
means that the warning light system is operating properly.
If the lamp remains on, or the lamp comes on while driving,
first check the followings.

 Empty fuel tank
If the fuel tank is empty, refuel immediately.

 Loose fuel tank cap
If the fuel tank cap is loose, securely tighten it.
These cases are temporary malfunctions. The malfunction
indicator lamp will go off after taking several driving trips.
If the lamp will not go off even after the several trips, contact
your Lexus dealer as soon as possible.
If the fuel tank is not empty or the fuel tank cap is not
loose...

 There is a problem somewhere in the engine, emission
control system, electronic throttle control system, automatic
transmission electrical system or warning light system itself.
Contact your Lexus dealer as soon as possible to service the
vehicle.

If the engine speed does not increase with the accelerator
pedal depressed down, there may be a problem somewhere
in your electronic throttle control system.
At this time, vibration may occur. However, if you depress the
accelerator pedal more firmly and slowly, you can drive your
vehicle at low speeds. Have your vehicle checked by your
Lexus dealer as soon as possible.

Even if the abnormality of the electronic throttle control system
is corrected during low speed driving, the system may not be
recovered until the engine is stopped and the ignition key is
turned to the “ACC” or “LOCK” position.

 

A month or so ago I finally got a check engine problem solved. Took it to the dealer several times. First time they said loose gas cap and tightened. Light came back on in a day or so. Second time they replaced the gas cap. Light came back on next day. Third time they replaced some evaporative control sensors. Light came back on the next day. Fourth time they figured out that Jiffy Lube had somehow disconnected a vacuum hose going to the air filter. This was creating a vacuum leak in the system that was setting off the warning. Thankfully the dealership is just a couple of miles from my home. It was a big hassle, but the dealership did not charge me anything and gave me a loaner every time. Jiffy Lube also gave me a free oil change the next time I went in.

 

I recall now after reading your post johnnieliu that the light went out after a day or so. When I called because the light was on and they said to check the cap, they also said they were willing to come and tow it or I could drive with the warning light on. With their OK in hand so to speak, I drove it and never had the problem again. That was the '99 several years ago.

 

To test the theory of the loose gas cap causing this problem in the event it should happen to me again, I loosened the cap, drove . ... tried it again 24 hours later and still cannot get the warning indicator to come on. Maybe Lexus fixed the problem on the'03 or some other combination of events is necessary.

(I do not recommend anyone try this, always follow the instructions in your owner's manual.)