Check Engine (p0171, P0330)

[lexus01]

What could be causing the check engine light? Here is what I have done troubleshooting the RX 300 (77,000 miles).

I purchased an OBDII reader and read codes P0171 and P0330. The car has difficulty up shifting from third to overdrive (sometimes it stays stuck in third) and other up shifts are somewhat rough (poorly timed). I drained and replaced the transmission fluid; the problem still remained.

I checked the timing and found that is was well forward of the 8 - 10 degrees BTDC. Since this car has direct ignition timing the computer adjust the timing I was unable to ajdust the timing.

I added Chevron's injector cleaner to the gas and I noticed that the shifting problem disappeared. I checked the timing and it was close to 10 degrees BTDC.

However, the knocking returned (with the P0330 code) and the shifting problems appeared again.

I think the poorly timed engine is causing the knock and the poor shifting of the transmission.

Could I possibly have an engine sludge problem?

Where should I look?

[SKperformance]

year of vehicle?

P0330

KS 2 Circuit Malfunction

i am not sure how this can be attributed to the tranny in any way

unless you are pressing the gas too much making the TC not want to engage

there are problems with the rx trannies as they are on back order

talk to the dealer

[lexus01]

KS

Thanks for the response. It is a 2000 model. How do you fix the KS 2 circuit malfunction? Does that have anything to do with the ECU?

As for the transmission, it got stuck in fourth gear and I was in stop and go traffic. I tried shifting manually into first and second and that did not work; it stayed stuck in fourth. Fortunately, the V6 engine was strong enough to move me from a standstill in fourth.

Later I stopped and checked reverse and it worked. When I went back to first it worked also.

What do you think? If it is a transmission problem, is Lexus going to replace it under the warranty even if I am past the warranty period by 7000 miles?

I have owned this vehicle since mile 4.

[J.B]

When you say "I drained and replaced the transmission fluid; the problem still remained.", did you "drop the pan and replaced what drained out of the pan" or did you do a complete flush and replaced the fluid? Just dropping the pan (as per Lexus' instructions) only replace what is in the pan, not what is in the torque converter/cooler.

Did you use the Toyota T-IV transmission fluid or any other type? Apparently, Toyota (Lexus) transmissions will self-destruct in contact of anything but Toyota's T-IV fluid.

Personnaly, I would still drop the pan to see if there is any metal filings on the magnet and/or debris in the pan.

Hope is nothing major!

Good luck

[lexus01]

JB,

I am going to drop the pan and look for metal the second time around. The fluid that came out of the drain hole was gray colored but the fluid was still slippery. I am using Type T IV fluid.

[J.B]

Error codes: I am reading my shop manual and it says:

P0330: Knock sensor 2 circuit malfunction (left bank )

P0171: System too Lean (Fuel Trim) (could be caused when the car runs out of fuel)

Gray colored transmission fluid does not sound good. Don't forget to replace the pan gasket.

JB

[SKperformance]

the greyish colour is usually form metal particles int he fluid

[lexus01]

I removed the transmission pan and the filter and was expecting to see chunks of metal but instead the three magnets on the pan held very very fine iron particles. The filter is a sealed type that I would have to break open to check for larger particles trapped on the input side of the filter.

I do not see anything unusual about the transmission fluid or the particles in the pan. The fluid was dirty but slippery.

[JPI]

I don't know if you received my email or not. But these are your problem. Check your Mass air flow sensor and A/F bank 1 sensor 1(by the firewall).

-Mass air flow sensor: this devices measure how much air going through your engine. If it doesn't work, it would cause your engine to run lean. And cause the knock.

-A/F sensor: Air/fuel sensor, this unit located on the exhuast manifold. It will provide the ECM with air/fuel going through the exhuast.

My bet is the A/F sensor but I don 't have the vehicle with me So i couldn't properly diagnost.

JP IMPORTZ

[sitnam]

JP,

A question that is not related to the current thread of discussion.

Do you know where the Mass Air Flow sensor and the A/F sensor are located in the RX330 model? If I suspect something may have gone wrong with the sensors, what and how should I check to see if they are okay?

Thanks for your help in advance.

[SKperformance]

the maf is in the intake hose after the airfilter

the air fuel is called an o2 sensor

there are 3 of them one on the fore and aft banks of the exhaust manifold and one after the cat

the only way to check them is with a scan tool to see there values

[lexus01]

JPI

I checked both A/F sensor for resistance and they are OK.

I swapped out a Mass airflow sensor from a friend's RX and that did not solve the problem.

Someone at www.clublexus.com listed a similar problem. The solution turned out to be a fuel injector that was not firing properly. This was tricking a sensor probably the one that tells the computer that it is warm-hot enough for up shift to overdrive. This makes sense to me. There are times when I am stuck in third (@3500-4000 rpm) and can get up shift to overdrive by deleting the error codes from the computer using my OBD reader.

A lean condition could be caused by a restriction of gas to the engine (clogged malfunctioning injector or another fuel related problem). The knock is caused by the too lean condition; there is too much air for the amount of fuel or there is too little fuel for the amount of air in the combustion chambers.

I am going to troubleshoot the fuel system, which means I will have to remove the intake manifold. I might as well change the spark plugs once the manifold is off.

[JPI]

For the record your local lexus doesn't use the Toyota ATF. Everyone using the Valvoline Dex now. They work for all transmission. ;)

JPI

[jlcpo]

happy holidays to you all.

another "out of course" question. we have 1153 code on our 99 rx300. check engine light comes and goes as it wishes. i found that 1153 is "air fuel sensor slow response, bank 2" which is - one of the oxygen sensors gone bad. question is - which one? which bank is one, which is 2? ox. sensors are $350 (internet) in exhaust manifold, five minutes to replace, i just need to know which one is it? please, email to jlcpo@msn.com

thank you

[lexus01]

Bank 2 is the side of the engine (or set of cylinders) closest to the radiator; Bank 1 would be the side of the engine (or set of cylinders) closest to the firewall.

Checkout Carson Toyota in California for discount Toyota-Lexus part (888) 747-4777. Ask for Collin.

[lexasm]

Lexus01,

First, sludge problems are completely related to the lack of oil services. If you have changed the oil/filter at reasonable intervals, I wouldn't worry about it.

Second, If your car is also buring alot of fuel, you may have a faulty mass air flow sensor (air volume sensor in Lexus terms). Not all that uncommon on RX's with some miles on them.

Thirdly, the transaxle is designed to not shift into overdrive until the transaxle fluid has reached 152 degrees. This is to prevent premature wear in the tranny and get the engine up to temperature faster so it meet emissions requirements faster. If this concern is particularly noticeable in colder weather, this may be the problem. Note: please make sure the fluid you used in the tranny is the Toyota T-4 fluid. According to the engineers, the wrong fluid will lead to slippage and possible failure.

The only oddity is the general misfire code(p0330). This could be an entirely different problem, or ist may be related to the dumping of too much fuel into the engine.

Let me know how you make out.

Good Luck

Lexasm

[jlcpo]

first, i need to say thanks to all who helped me with my previous message. check engine light's gone, all we did is to replace fuel cap, it came on one more time, we had code reader plugged in and out, it showed p1153 but the light vanished 5 minutes after and did not come back in weeks. amen! but what i found inbetween is a useful website:

http://www.diagnosticdialog.com/

this one has an interactive part that will describe a code for ANY car and ANY code, even those for internal use ones (like we had with p1153 ) autozone did diagnostics for free, i have no doubt most of them big autostores will do the same. also, should you ever consider buying chilton's suv repair manual 2003 ( i did because it claims to have 99 lexus rx 300 and my honda crv 2002 in it) - do not waste money, it's junk. fork for original manuals if you are like i am - addicted doityourselfer.

[JPI]

I wouldn't say it's the gas cap. Gas cap code is po441. Good luck.

www.jpimportz.org

[APN]

I don't know if you received my email or not.    But these are your problem.  Check your Mass air flow sensor and A/F bank 1 sensor 1(by the firewall). 

-Mass air flow sensor:  this devices measure how much air going through your engine.  If it doesn't work, it would cause your engine to run lean.  And cause the knock. 

-A/F sensor:  Air/fuel sensor, this unit located on the exhuast manifold.  It will provide the ECM with air/fuel going through the exhuast. 

My bet is the A/F sensor but I don 't have the vehicle with me So i couldn't properly diagnost. 

                JP IMPORTZ

Hello,

On my 99 RX300 (84k miles) I had code P0171, I could loosen the sensor and the local shop replaced the bank 1 A/F sensor but the same error appear again . Can you please give more direction.

Thanks

APNRX300

[aktansrt]

happy holidays to you all.

another "out of course" question. we have 1153 code on our 99 rx300. check engine light comes and goes as it wishes. i found that 1153 is "air fuel sensor slow response, bank 2" which is - one of the oxygen sensors gone bad. question is - which one? which bank is one, which is 2? ox. sensors are $350 (internet) in exhaust manifold, five minutes to replace, i just need to know which one is it? please, email to jlcpo@msn.com

thank you

Why don't you replace one, and see if fixes the problem. If it does not, it should be the other sensor, unless both of your sensors are gone bad. Which is quite unlikely.

[mikey00]

first, i need to say thanks to all who helped me with my previous message. check engine light's gone, all we did is to replace fuel cap, it came on one more time, we had code reader plugged in and out, it showed p1153 but the light vanished 5 minutes after and did not come back in weeks. amen! but what i found inbetween is a useful website:

http://www.diagnosticdialog.com/

this one has an interactive part that will describe a code for ANY car and ANY code, even those for internal use ones (like we had with p1153 ) autozone did diagnostics for free, i have no doubt most of them big autostores will do the same. also, should you ever consider buying chilton's suv repair manual 2003 ( i did because it claims to have 99 lexus rx 300 and my honda crv 2002 in it) - do not waste money, it's junk. fork for original manuals if you are like i am - addicted doityourselfer.

Bad link??