04 LS430 217,500 miles

Tons of info here on the issues I am having, but I wanted to share this experience as I move forward in finding the problem and eventually the solution.

CEL, MIL (Check VSC), and Trac Off have come on three times in last 2 weeks, exactly 1 week apart after clearing codes. Codes read on Bosch OBDII 1000 are as follows: 0455, 0446, 0441, followed by 1 Inc (meaning car not driven enough to complete the monitor), EVAP (EVAP System Monitor), MISFIRE (Misfire Monitor), FUEL(Fuel system monitor), COMP (Comprehensive components monitor), CATALYST (Catalyst Monitor), 02 SNSR (Oxygen sensor monitor), O2 HTR (Oxygen sensor heater monitor).

I checked all hoses in the EVAP system (under the hood) and found none that were loose, visibly cracked, etc. I have yet to get underneath to check the charcoal canister and other connections in that area. I'm still a bit unclear on where exactly that assembly is (searched here a little but haven't really gotten into it). I noticed the MAF sensor mounting screw anchor had come up out of its hole, and was able to secure it, eliminating the small gap it had created. For those wondering, there is a small metal anchor pressed into the plastic, and it had come loose, presumably when tightening down the screw. JB Weld on the knurled area kept it in place. I initially thought this may have been the problem, but 7 days later, codes came back.

Next step is air induction smoke test, due to be performed Friday afternoon. If a leak is found, I will address that issue then. If not, I assume it could be a bad EVAP sensor, O2 sensor, or some other electrical component within the system. I am sure the mechanic will run a diagnostic scan as well when they get my car.

This issue comes on the heels of a new starter (Lexus dealership), and new radiator (DIY).

I ordered a new Coolant temp sensor, and will install that this weekend regardless of the induction test outcome. Also planning to install new VVT sensors this weekend. I figure it can't hurt to switch these parts out considering the mileage.

 

Start with making sure your gas cap is tightened. Then check vacuum hoses connected to the evap vacuum switch. The switch itself may be faulty. Easy DIY replace and inexpensive switch. I found this thread to be helpful > https://www.clublexus.com/forums/ls-...procedure.html

 

I failed to mention all diagnostics I went through, but I did secure the gas cap and check all hoses, including those connected to the vacuum switch. Thank you for that link. In my searches and reading, I had not stumbled across that one. I will plan to clean up the switch this weekend and see if it helps.

 

A word of advice.....With all the codes, try to get the best professional and reliable diagnosis before thinking about throwing parts at your old car other than anything obvious or inexpensive like rubber hoses. Good luck.

 

Pretty much my initial thinking, and the reason I scheduled the induction test. I will even hold off on changing out the hoses until after the test. If it is indeed a leaking hose, I want to know it for a fact.

 

I offered the link not for cleaning the vacuum valve, but for testing and/or replacing it. Sure you can take it to the dealer and have them diagnose it, but do know that the issue you have is not one that the dealer can easily or accurately diagnose. (as confirmed in that thread, and others.) The evap vacuum switch and hoses can be easily and inexpensively replaced, if you're DIY inclined. After that, it gets more involved and more expensive to diagnose and fix at the dealer. How much do you trust the dealer? Perhaps they'll tell you it needs a new canister. Price that part alone. (My '01 with 300K has never needed a new canister.) I'd DIY replace the vacuum switch for $60, and any hoses for a few dollars first, but if you prefer to not throw a few inexpensive parts at it, take it to the dealer for diagnosis labor, parts and install labor, but you'll have to hope they fixed the problem, and didn't do more than was actually needed. My $.02. Good luck.

 

I understood the reasoning for the thread link. I learned quite a bit reading through it, beyond the cleaning part. I noticed the OP ended up having to replace his even after a successful cleaning.

The $60 induction test at my local indy is an absorbable cost to see if I have any leaks. If none are found, I will start by testing and/or replacing the switch, replacing old hoses as preventative measure, and monitor going forward. I have looked at canister prices, and don;t like what I see!

 

Deadguy........If you have a good relationship with the service manager at Lexus and discuss with him your issues you might be going in the right direction for the minimum diagnostic fee. Once again, if they do what they say they will do.....they have the ability with their equipment to open and close certain modules to narrow down the possible area/areas of your issues. You might get lucky and find out it's not a big deal, and if they point to an issue and back it up, you can even pay the extra dollars for them to do it. At least if you have an issue and if they are reputable, you have some recourse that it wasn't corrected. On the other hand, if they point to the charcoal cannister, which is an expensive part and job....you have the option to go to a trusted Indy to have it done there. Sometimes, I've heard that the canister leaks and can be repaired(I've been told). Good luck and let us know how you make out. The key to this equation is having a good relationship with the dealership you are going to. If you are not comfortable, go elsewhere.

 

Some detail for 2004 LS430.

 

This looks to be a GS. Is location of Charcoal Canister identical on LS?

 

Interesting- maybe it is similar to other models- here is zoomed out on the page to see better for 2003-2004LS430.
Here is another might be interest for you.

 

Thank you. Parts in diagrams are in different locations but the general path of the vapors is understood.

 

No prb, plz check updated pics above- there were multiple drawings in the detail for some reason so see if these match better for you.

 

Got it. Very helpful. Thank you.

 

I don’t remember reading anything on this forum of a member who actually paid to have the charcoal canister replaced. Besides the part being expensive and being buried over the rear axle, it’s always a possibility that the replacement will not resolve the leak. Imagine laying out all that doe and still be glaring at the check engine light?