az-dave

So...did replacing the valve fix the problem?

Did you buy from Lexus dealer?
Im finding part number: L15330-46010 or 46011 from lexus dealers in AZ...they want $121-$163 depending on who I call...non-refundable.

Thanks!

jhill20

iTrader: (1)

Always remember folks, having a problem such as this is diagnosed properly isn't the worst idea prior to "throwing" hundred some dollar parts at it......

Just sayin...

az-dave

Ive paid Lexus to Diagnose problems before...they've been dead-wrong each and every time. (I have a huge thread on the "Limp Mode" problem) They get a code, and the first thing they want to do is start replacing sensors, (or in my case "Your Entire Throttle Body needs to be replaced", which was nonsense!) etc until the problem is gone...This is because each code can have 2 or 3 actual causes, and they really dont have a crystal ball telling which part is the cause...thats what old fashioned mechanical aptitude skills come into play. Ive experienced this not at just one Stealer, but every one Ive been to in Phoenix...4 of them....Not impressed. They wanted to replace my entire Throttle body because the Idle TPS sensor wasnt the problem, rather it was the Throttle control motor...and they have no way of testing for it, the code was TPS/ACCEL System...so much for Diagnostics Lexus! - Different Story but same result. Diagnostics are only as good as the person doing it, and I trust myself far over most of them except in cases where good old trouble shooting, 20 yrs of experience, and critical thinking leave me stumped...which has been one and one time only. And Ive NEVER EVER just start spending hundreds of dollars replacing parts...thats what the Sdealers do...fist-hand experience.
Dont get me started on the Sdealers ideas to fix my Master Cylinder problem 4 years ago...they were Stumped, and started replacing stupid things like the Battery Terminal...Idiots! I left the Sdealer after they said "Everything is fine", and the Goddamned brakes went out completely (as in NO Brakes) 5 miles later. Thank God I was coming to a stop and only doing 20 mph...Parking Brake saved me. Turned off the engine and the brakes started working again...took back to Sdealer...they cant find problem.

I found problem after towing home...the Hydraulc Brake Booster was intermitantly cutting in and out, which caused the ABS System Computer to engage the ABS randomly but kept it on, Cutting ALL Brake line pressure thru the Master Cylinder. I Troubleshot and fixed that one myself too...

Oh..and Lexus charges 1-hr labor for a Diagnostics....usually $120-$160...and they never ever say what they find will for sure fix it, cuz they know a code, such as P1349 can be caused by a plugged OCV Filter, Bad OCV valve, Malfunctioning VVTi Cam, VVTi Sensor problem, or the ECU Itself. So...how do you think Lexus would go about fixing that code...If honest they would start by checking the Filter, then the OSC Valve, then the sensor, then the Cam, then the ECU. There is No other way to do it, as ANY of those parts malfunctioing will throw the same code, and casue the same signal errors when reading Freeze-Frame OBDII Codes and data.

I need a breather!

Sdealers are not the answer to all, and they must be "used" carefully to protect Your best interest...

jhill20

iTrader: (1)

Hey did not mean to get you all riled up sir. I just hate to see people follow advice from a forum regarding an issue that does require troubleshooting. This is coming from a dedicated, (that's all I do), driveability tech. My apologies. And no I do not work for a dealer. I'm in the independent.

az-dave

No worries, you didnt rile me up. I just needed to vent my frustration once again at the d(st)ealers out here in AZ.

Its not just me, My wife has an RX300, and the dealers tried pulling the same crap with her, replacing stuff that didnt need to be replaced trying to find a code...I got pissed and took it back and told them to remove their crap and give my money back...after 10 minutes I won. It ended up being a loose vacuum hose.

The problem Ive found with most dealers is that they dont think critically, and they are just there to make money off people they think dont know anything about mechanics. Its ridiculous.

My last encounter was with Arrowhead Lexus wanting to charge me, get this: $375 in labor per rear wheel hub assembly to remove and press in new wheel bearings...I removed the hubs and brought them to the shop...they said they would have to charge me the same amount as if they were installed because "Its very techincal and precise what needs to be done" I got pissed, told them not to treat a person who has worked on cars for 25+ years like a dumbass and left. I had the bearing pressed at Napa for $50/hub.

Oh...and the reason I replaced the wheel bearings: because after taking my GS300 to the dealer due to a noise that got louder and louder over 2 months, they told me it was "probably" wheel bearing noise. I did the front bearing myself. Noise still there. Nice. So then they say "Then its probably the center bearing on the drive-shaft" Replaced that, based on Lexus genius techs, noise still there...then they said it was probably the rear-end. I tore that apart too, new bearings, seals, etc...noise still there...at this point Lexus Dealer is completely stumped. So I put my car up 3ft off the ground at home, put it in drive with the parking brake slight on to simulate load, and crawl underneath and listen very very carefully...I determine it must be the tranny...Lexus couldnt have done that from the beginning?

It ended up being the Orbital Gear in the Transmission having had a tooth ruined after 225K miles. I bought a Tranny from a 2003 with 38K miles slapped it in (Lexus said it wouldnt fit, thats only because the electronic gear selector on the side of the tranny needs to be swapped) and noise gone.

I have other stories too. Like I said...Ive tried 4 different dealers here in AZ, and I will never take my car to a Lexus dealer again...rip-off X 100. Im certain some dealers elsewhere are good...but not here.

Ok...another breather needed...sorry for hijacking thread...all future posts will be related to the OCV system. Which I think I may have fixed in my case.

az-dave

Ok, As the Saga goes...

I did extensive research and found the Lexus Diagnostics Procedure for checking the VVTi System on the GS300. Its actually fairly straight forward and makes a lot of sense. Basically the ECU sends a Pulse-Modulated 12V signal to the Solenoid (OCV Valve), it CANNOT be tested with a hand held Digital Voltmeter. The only way to check the signal is with a Oscilliscope or Digital tester With Microsecond interval. 99% of the time the ECU is Not the problem. The Oil is pumped thru the OCV filter into the bottom of the OCV valve and then depending on the signal (advance / nominal / retard) the plunger inside the OCV Valve is continuously moved allowing different amount of oil pressure to be diverted into the advance or retard side of the VVTi Cam Pulley-Actuator. If the actuator is operating properly it will then advance or retard the actual Cam, which has a magnetic tab on it that then sends a signal to the Cam-Shaft Position Sensor (which almost never goes bad), and that signal tells the ECU the position of the Cam so the ECU can adjust the signal back to the OCV Valve.

The Procedure:
1) Check OCV Filter, Clean as Necessary, re-test drive vehicle prior to Step 2.

2) Check Operation of OCV Valve: (Engine must be fully warmed up)
a) PASS: Unplug OCV connector - idle should not change
b) Connect 12V DC across OCV terminals after step 2a:
i) PASS: Engine Stalls or almost Stalls when voltage manually applied to OCV Valve terminals, No Change to idle when OCV disconnected from plug - Go To Step 3
ii) NP(Bad): No Change to idle when Voltage Manually applied to OCV Valve, or large change in idle when OCV Valve disconnected from plug at idle- Replace OCV, Plunger/Solenoid not operating

3) Check Signal from ECU to OCV Valve Plug (may unconnect or tap into wires)
a) PASS: Pulse-Modulation Signal changes with Engine RPM Go to Step 4
b) NP: Pulse-Modulation does not change or no Pulse-Modulation Signal from ECU to OCV Valve plug - Go To Step 5

4) If Steps 2 & 3 Pass Replace VVTi Cam-Actuator:
a) Remove Timing Belt, remove VVTi Cam, Clean Cam Oil Journals, Replace Cam-Shaft Seal, Install new VVTi Cam
b) Test Drive, if replacing OCV Valve & VVTi Cam have no effect move to Step 5

5) Check Signal from Cam-Shaft Sensor (this obviously could be done as Step 2, but the general idea is that if there is a pulse-modulation signal coming from the ECU, then it must be deriving that signal from the Cam-Shaft Sensor)
a) PASS: Signal Sent changes with RPM - Go to Step 6
b) NP: Inconsistent or Non-Existent Signal: Replace Cam Shaft Sensor

6) Check ECU:
a) PASS: Signals from both Camshaft wires and OCV Valve consistent at ECU and at sensor & OCV Valve (in other words check the signals at the wires directly at the ECU AND tat the sensor and OCV Valve - there may be an intermittent break in the wires causing intermittent incontinuity of signal while driving) - Go to Step 7
b) NP: Replace Wire Harnesses between ECU and Sensor and ECU and OCV Valve - Re-Test Drive

7) Check Cam-Shaft and OCV Housing Oil Journals & Oil Presure
a) Disassemble Timing Belt, VVTi Cam Assembly, remove Intake Valve cover, remove all Camshaft Bearing Caps and inspect for excess wear, clean all internal oil passages.
b) Check Oil Pressure on Supply Line to OCV Valve (requires some special equipment to keep oil from spraying everywhere) - You can also do this by removing the OCV Valve putting a towel in its place and turning over the engine for a few cranks, oil should come out pretty fast, and will make a mess.
i) PASS: Oil Pressure supplied to OCV & Cam Journals free of blockages and Camshaft Bearings good - Go to Step 8
ii) NP: Replace all worn or inoperative parts, including Oil pump if Oil starvation is noted.

8) Replace ECU

Notice Replacing the ECU is Dead-Last...just after taking apart the entire upper end. Its pretty much a common-sense Logic process eliminating the most common/easiest to cure sources of the problem. My hunch is if Steps 1-8 dont work, the engine is "worn-out" and may have some sticking valves or other issues sending bad signals to the ECU which could take days upon days to trace and track...which is why in these instances dealers replace entire motors...the motor may cost less than the labor when all else fails.

If Steps 1-8 dont work, then your the lucky winner of an undiagnostical and unfixable problem...crack open a 12-pack and drink away.

I hope this helps future people with this problem.

az-dave

So I replaced the OCV Valve after testing it and verifying it was bad. Car ran great until Tuesday, when a rough idle came back. No codes.

So, I decide to check the wires, at night they were glowing and a small arc, so I decided to replace the wires with new Lexus ones, and while at it I replaced the Plugs too.

Drove the car 50-60 miles Tuesday and Yesterday drove like perfect...then all of the sudden, it starts hesitating, and a very frequent random misfire is now happening. No Arcing of the wires is observed, no Codes, No CEL. At idle it will drop to 300rpm, and go up and down. Under light acceleration you can definitely feel the tugging caused by the misfire, and full throttle and 80mph it runs fine but you can feel the slight chugging caused by the misfire.

Im seriously now at my wits end...I fix one problem only to have a completely different problem pop up out of nowhere for no apparent reason.

Im now suspecting a coil pack going bad or possible very sticky valves.

Maybe I will just drive the F-in thing until whatever the heck the problem is makes itself unmistakingly known...then I can post pics of a mauled engine?

Hell...Its got 250K miles on it...what do I expect....this is more of a puzzle to me now than fixing the car, since its a secondary car for me...just sad to see a GS300 sit there sleeping.

az-dave

Update: Cause of Misfire has been located and under repair...something Im willing to bet may have never happened before:
https://www.clublexus.com/forums/per...ml#post6176002

az-dave

jhill: Found the cause of the misfires, pretty incredible sequence of events that led up to this, I created a new thread, as once the VVTi OCV Valve was replaced it was obvious there were multiple misfires concurrently happening, and the VVTi codes just happened to be the only one throwing codes, please enjoy, I included nice pics of what I found...its pretty stunning:
Update: Cause of Misfire has been located and under repair...something Im willing to bet may have never happened before:
https://www.clublexus.com/forums/per...ml#post6176002

PrLWhtGS3

iTrader: (2)

i had most of the similiar symtoms, i had the VVT sensor changed and timing reset all better so far

RSalmeron

Anyone have oil in the connection ports to the ECU? I have the same problem with the engine lights and problem codes. Checked the OCV, Cleaned the filter and no success.

jchamb

I had all the same symptoms and CEL codes as coco-bun on a 99 GS4. Installed new OCV on LH/Driver's side and that fixed her up. Coco's pics were accurate for me, and beside a little bit of a tight squeeze, the part can be installed without the removal of anything other than the plastic engine cover.

execlex

I cleaned my drivers side/LH OCV and the port it sits in and the CEL & VSC came back after about 20 miles. about to replace the part. did you replace the filter as well?? I'm confused as to where this could be in the 1UZ-FE (mine's LS400) and I figured I would replace it because it's only like $5-$8 from what I hear... but if you have had success with only the OCV replaced I need to get it done. hope to hear back from anybody

Tinker

So far the part number for the OCV that I was able to find out is 1533046011. I want to be sure that this is the right part for GS300 1999. It seems that it is only available at Lexus and Toyota dealerships and is not cheap. How can I verify the exact part number?

sakataj

iTrader: (182)

^ i know the GS400/GS430 part #'s are in here,(not having ever seen this thread) i did a DIY for the V8 guys post # 67

https://www.clublexus.com/forums/per...ve-filter.html

but since the original DIY was made for the GS300 guys i would assume that part # is in there also, just gotta read some of it