fubass

I know I'm a new member, but I did throw a search on the forum first!!!

...

But found nothing

Question!

Girlfriends 1999 RX300, got 140k miles on 'er and for some reason today it decided to be a jerk! Got a stutter/ jerky acceleration between 1500 and about 3k-ish rpms like.. idling or flooring it is the only times when it goes away.

anyone got a good clue on what this is? Any help would be amazing!



All these threads about gunk has got me worried lol

fubass

so... update.. did one of them scanny thingys... orileys guy said "upstream O2 sensor, and number 1 knock sensor"

1. Will these two defective parts create this problem? ($300 down just in parts, so you know that means $1000 Lexus dealer.)

2. Where is the #1 knock sensor, and upstream O2 sensor located? I'm an ex-commercial aircraft mechanic so I can do sensitive work, just need to know where they are at. Is there any sweet online reference drawings? (there was no manual when my girl bought the thing)

carguy07

O2 sensor is pretty easy, but there are two of them, one in each exhaust manifold. Need to know which one you might need. They are about $100 a piece. Knock sensors are buried under the intake manifold which needs removed to get at them. Hopefully you don't need to mess with them.

The first thing I would do is clear the codes and drive it until you see the CEL come back on. Then immediately read the code and post what you find. I will send you PM to help you out with the service manual.

fubass

Yeah, there is no driving it right now, it's completely bogged up between 1500-3500+ RPM's so its pedal on the floor or nothing, swapped the easy to access O2 sensor yesterday with no result, so gonna swap the annoying one today to see if it fixes the problem. If the O2 sensor was the root cause does the knock sensor get better or still need to be replaced?

fubass

another update.. and need some help... replaced the correct O2 Sensor and no luck...


this youtube link is a link of the sound the car is stuttering on, remember the codes called out #1 knock sensor and the O2 sensor just upstream, got a new sensor.. but problem persists... will a knock sensor continue the problem that i currently have?

you can hear the jerkiness of the engine, embedded at 17 seconds so if you listen to it over and over again. This is how the car's throttle sounds like. We are slightly uphill, so even though we are stopped the throttle is down, it really feels like only half the motor is even working unless you floor the pedal, then it works fine until you STOP accelerating, hold the pedal constant and it poops out with the stutter again...

http://www.youtube.com/watch?v=mb8bU...tailpage#t=17s

so... final question, is it the knock sensor perpetuating the problem???

Thanks for your time!!!!

carguy07

There is some confusion out there regarding the which codes point to bank 1 or bank 2. What O2 sensor code did you get and which one did you replace? Did you clear the codes after installing the new sensor? What codes are you pulling now?

fubass

replaced both upstream O2 sensors, still getting code for bad no.1 bank knock sensor... which is poop, and now my saturday is going to be poop pulling off this stupid manifold

carguy07

So just the knock sensor code now?

fubass

7 hours touch time, a buddy who has played with a motor before, and a 6 pack, to replace the sensor... car works better than before!!! And it was a verrrry big pain in the rear, but definitely able to be a DIY maintenance project.

kind of upset now that the dealer sold her the car with the check engine light on.
but... lesson learned... this is the first time i've heard that you can plug a computer into a car and have an electronic diagnosis.

fubass

bah, having coolant problems now. stupid thing. plus i should have replaced her plugs while i was in there.

Hindsight is 20-20 I suppose

This RX300 engine was designed by either amateurs or people with no concept of space constraints I swear! lol

Lexmex

What coolant problems are you having.

Keep in mind that the RX300 is partially based off the Toyota Camry platform, but I do agree with your opinion on space constraints.

Carver

It sounds like a pretty nasty little car as far as a lack of long term maintenance goes. These things will run for a long time with a little care. Obviously, it needs some.

You should go to lexus.com and register as an owner which will give you access to everything done to the car at a Lexus dealer since new. It will also give you access to the maintenance schedule if you are missing the books.

Things that need to be done:

Timing belt (if no proof it was done at 90k, bout due again anyway)
Water pump
Plugs (if no proof)
Trans drain and refill
Change radiator fluid with Toyota super long life
Change PS fluid
Change brake fluid
Change oil and filter

Possible problems:

IAC needs to be cleaned
MAF sensor needs cleaning
Coils at some point
Suspension components


That's all I can think of off the top of my head but if you give this car a chance and give it what it needs I think you'll be impressed.

fubass

I'll take your advice and register, even though it ain't my car i know i'm screwed into taking care of it. Timing belt was just done, don't know about the others, so its alllllll subject to R&R.

The leak has slowed and is going away by itself as i keep poking the hose clamps the best i can. Been just filling with water until the thing is fully troubleshooted out lol. Once its stopped leaking completely I will will it with the good stuff

But maaaan the sensors on lexus vehicles absolutely CRIPPLE the car if anythings wrong.

fubass

Hello again...

you may have been in my last knock sensor/ O2 sensor thread here

Which i replaced the bank 1 knock sensor and O2 sensor by it. She was too broke to deal with replacing it all at once and it really wasnt too bad to dig and replace out. So we only replaced the faulty sensors and closed her back up...

she ran perfect for about 500 miles.... check engine light on again... BAM the car is undriveable again as it just stutters and barely stays alive unless you floor the gas pedal....

P0125
P0325
P1135
P0171
P1155

..... really? eff this car ! I'm calling up the dealer that sold it to her 6 months ago and giving them a piece of my mind. (Even though she didnt buy any warranties ect. they still sold it to her "as is" for $9500)

Long story short... Need some help with the codes and taking the PROPER action on fixing this thing up for good. I'm an airplane mechanic so if i get directions i can do anything. I just need to know the best route....

Help!?!?!

hypervish

Reset the codes, and see which code comes up first.

P0171: Clean the MAF
P0125: Ignore
P1155: Change/Check 02 Sensor: Bank 2 Sensor 1
P1135: Change/Check 02 Sensor: Bank 1 Sensor 1
P0325: Check/Replace Knock Sensor

Look's like whoever sold you the RX, knew it had problems. These car's are extremely reliable, and don't have too many problems. $9500 is a high price to pay for an RX with many problems especially a 99'. I paid 14k for my 00' 5 years ago, and it's been trouble free.