mgmoore7

We purchased a 2006 ES 330 with 113k miles that is in excellent interior/exterior condition, drives great and almost everything is working but, see #1 below. It was purchased as a 4th car for my wife and teenagers to drive around town. I paid 6,800 for it before tax, tag, title. Had multiple owners but was well taken care of from a general maintenance perspective according to CarFax. Thanks for reading. I wish my first post was a little more positive.

1. By the time we got home, the CEL came on. It is a P0420 ("Catalyst System Efficiency Below Threshold (Bank 1)". After some reading, sounds like this could be a myriad of issues from simple to complex. I will start at the simple and try to diagnose if it is a sensor or the Cat. The carfax states an Oxygen sensor was replaced at about 100k but no indication of which one. Also, we haven't driven it enough yet but it looks like it is getting poor MPG, between 13 and 15 so far according to the computer. We are going to need to calculate it ourselves. I know that a bad cat or potentially other related failings could cause poor MPG. I was hoping to at least get around 20mpg with easy driving.
2. I should have checked the gas door but it was very strangely extremely dirty (see pic). I have no idea how it could get like that. Any ideas?
3. There is also a C1241 code (Low battery positive voltage or abnormally high battery positive voltage). I have not looked into this yet since it was a much lower priority.
4. It has an aftermarket single din radio but want to replace it with a double din with Apple Car Play and a backup camera. I will work with Best Buy or Crutchfield on this. Best Buy installs for free usually but their inventory appears to be very limited right now. I don't think I want to do it myself. I have done multiple myself but
5. We need to purchase floor mats all around.
6. The front brakes are less than 30% and the dealer gave me pads to replace. We will do that at some point in the near future.
7. The left passenger window does not work from either switch. Not a big deal and we knew this when we bought it. We live in Fl and run the AC 99% of the time so don't really put the rear windows down often.
8. I see now that this requires Premium Gas. Never expected that and should have checked.

I have a on its way. I used to have a different version that worked for Android anyway. This one doesn't appear to have a monthly subscription for use and highly rated so I bit the bullet. I have 3 other cars so, it won't go to waste.

While I am feeling some remorse, mostly because we didn't get 20 miles without notable issues, I also know that just about any high mileage car could have issues and buying a car like this can be risky. We bought the Lexus over many other options because of the current used car market is nuts, this was less by thousands than cars like Elantra, Camry, Accord that usually were in much less condition and had more miles but they usually were newer such as being a 2013 Hyundai Elantra.

I am mechanically capable but in my life today, it is more about the time than doing the work. That said, I don't want to sink hundreds to thousands of labor / parts into a 7k vehicle.

My plan for right now:

1. Track the gas mileage
2. Use premium gas for now (just put in regular so will have to wait for a tank). Not happy with myself for not knowing/checking this. it obviously increases the cost quite a bit.
3. Put in some Redline Fuel System cleaner.
4. Watch the videos by Eric the car guy on diagnosing the CAT
5. Reset the codes once I get the OBDII Scan tool
6. Determine if I have just bought a lemon and should move it on before sinking more $ into it.
7. Listen to your suggestions and keep learning.

By the way, my wife really likes the car and so does the rest of the family. It drives really nice, is quiet, smooth, comfy, and tight. It is the first vehicle that my wife has ever liked how the seats fit her.

Questions:

1. Thoughts on anything above?
2. Is there a way to lookup the options included for this specific car. It seems like a base model but I am not sure Crutchfield is asking if it had a nav system but since the stereo has been replaced, I don't know.
3. Any suggestions for floor mats that everyone likes

If it weren't for the Catalyst code, I think I would be really happy right now.

Matt

LeX2K

Has that car been flooded? What does the underbody look like? I can't otherwise explain how the filler got like that unless it simply sat a long time. You shouldn't ignore C1241 in fact I would try and address that first.

mgmoore7

That was my first thought. I can't imagine how it would have been flooded and be in such good condition otherwise. I only took a quick look at the underside and did see some small spider webs and that made me wonder if it had sat for a while. I have not looked at it in detail underneath yet.

June1978

I've had both P0420 and P0430. Had to replace the cat. FYI- go with a genuine toyota/lexus CAT.

p0430 is the cat in the front by the radiator

p0420 is the one on the rear of the engine

HomerJay

Sorry, that's frustrating especially on the first drive home. Did you check for codes or readiness monitors status before purchase? Assuming no, I wonder if the seller was not honorable and erased pending or current codes.
Was the seller private or a certified dealer?
Have you contacted the seller for feedback?

oldlexguy1

P0420 means it won't pass inspection, right? I'm not 100% sure about the law, but it must be illegal to sell a car that doesn't pass inspection. (Unless it's clearly disclosed before the sale)

mgmoore7

Probably but there are no inspections in FL.

mgmoore7

I did not check for codes, should have, lesson learned but in this case doubt it would have mattered because the P0420 code triggers the engine light which was not on when we purchased it and did not come on when we test drove it. I called the dealer today and it is hard to know, there is no proof any anything one way or the other but there is a good likelihood that they cleared the codes and hoped for the best. He said there were no engine codes but I would expect that it is normal practice for these smaller used car dealers to clear the codes.

Earlier today, I cleared the codes and we just drove it about 20 miles and the engine has not yet returned. Crossing my fingers.

mgmoore7

Thank you, I have read the same by several others. They are not cheap for sure and according to the videos I have seen, not impossible but not easy either to do the replacement.

fortitude

If you do change the cat, be sure to buy new studs and nuts that connect cat to front exhaust pipe assembly. Studs are an E-Torx socket (e-8?). Also the gasket to head & gasket to front exhaust assembly.

As LeX2K said, my first response as well, picture of fuel door looks like flood damage. Never dealt with this, but wouldn't the interior start to smell at some point? Or are the rugs new? Its easy to pop out rear bottom set cushion. See what the condition is underneath

Using you scanner, look at live data
Long & Short term fuel trims, each bank. If these are high (not under load) it means computer is pushing more fuel into the engine (13mpg is not good) and eventually will kill the cat
2002 specs -
A/F voltage will show if they are working or deadO/2 voltage will show if cat is functioning (once warmed up)MAF readingFuel system status - must reach CL (closed loop) status once proper operating temp is achieved
Coolant temp - 176 - 203F after warm up

If you plan on fixing the car yourself, I recommend the Toyota/Lexus Service Manual, located HERE

C1241 (2002 spec) Low battery voltage

1. vehicle speed 1.9mh or more and ECU terminal IG1 voltage is 9.5v or less (for 10 seconds or more)
2. terminal IG1 voltage is less than 9.5v, there is open circuit in motor relay or in solenoid relay, or solenoid circuit malfunction

• Power source harness and connector
• Battery
• Charging system
• Power source circuit

1. Remove ECU-IG fuse from driver side j/b
2. Check continuity of fuse - OK=continuity
3. Check Battery terminal voltage OK=10- 14V
4. Measure voltage at Skid control ECU - Trun ion on, measure voltage between IG1 & GND (1,2,3,4) OK=10-14V

These cars can run for many, many miles. Figure out the voltage issue and mpg issue. After diagnosing (not the parts cannon method) & pricing out solutions, then determine what you next step is.

As for learning more about these systems, I enjoy watching South Main Auto (YouTube) He is brilliant, especially electrical.

fortitude

I also want to add, read the fine print from the purchase agreement. See what responsibility to remedy the issues can be placed back on the dealer you bought it from

mgmoore7

Thank you so very much for the extensive reply. Very helpful.

I didn't sleep much last night worrying about if the car was flooded. There were 2 more factors that got me thinking about it more.
1. The stereo appears to have been replaced recently with a single dim unit. After some reading, it is common that the stereos are damages more often than anything else with water damage. It could simply be that the radio had issues or they wanted Bluetooth and they wanted one that worked or had Bluetooth.
2. The codes could be caused by water damage to electrical system but just as easily not but still once a mind starts worrying.

I just got done looking it over a bit more. The car must have sat a while as it does have quite a few spider webs underneath. Under the car, no rust, corrosion, etc that would not be expected for a 15yr old car. I pulled the spare tire out and compartments around it. No indication of water anywhere. The car doesn't smell like mold,mildew at all, my wife can smell that from a mile away. I want to pull a door panel and maybe the back seats to see if there is anything there and then I will move on. Hoping for the best. See below, the gas inlet may be a false lead.

Regarding the gas door, after some research online, this is definitely not unique although not common discussion maybe because most people don't care what is under the gas cap. Theories include, never cleaning it, ever. Leaky gas cap. Road grime over time. A drain/vent in there that could be clogged. Several pictures I saw online look very similar. One website stated "The black build-up surrounding the gas cap is often a mix of grease and mildew deriving from the evaporating residues of fuel. " So, I will check for the vent system and probably clean it up and move on.

June1978

The front CAT was "easy". Some of the studs were rusted and a little hard to take off. One of the studs that connects the CAT to the exhaust (bottom of car) ended up breaking. Back CAT was somewhat of a pain. Each took about an hour to replace...BUT...

My friend is a mechanic at the Toyota dealership so he does side work after hours at the shop. He's done a million of these so he was familiar with the process. He had the tools, lift and spare parts (studs, screws etc) to complete the job. I can't imagine doing this in the driveway- especially the rear CAT. He switched tools a bunch of times to get to hard to reach places and to remove the rusted/stuck studs. Didn't look fun

FYI- I got the CAT's from Ebay with all gaskets- P0430 CAT was $540 shipped- P0420 CAT was $590 shipped (the seller was a lexus dealer in Arizona)

Don't waste time trying to change O2 sensors etc (also expensive)- these codes usually mean CAT. Those liquids you pour in the gas tank that apparently clean the CAT and turn off the CEL didn't work for me either. I watched a million youtube videos and none of the fixes worked

mgmoore7

Thank you for the tips. A bad cat definitely could impact MPG and power. I don't think the vehicle feels low on power but it is possible since I just got it and haven't driven it before this issue. I have used Redline fuel system cleaner for a long time as a preventative and in higher mileage cars I have had, I swear it helped the vehicle run better but that is more a feeling than fact. I don't believe in miracle cures but I do think that additives can be helpful in the right circumstance.

fortitude

is a link to remove rear bottom seat cushion. When pulling up the seat cushion, I also push it slightly toward the trunk

With proper maintenance, these cars run for ever. Also, mileage & age doesn't automatically mean change out the part, even though it still works... Use Lexus Maintenance schedule as a reference.
Example - fuel injectors. Car has 120,00 miles, injectors are "old", replace with new...... Test them & if they still function to specifications, keep them....
Unlike some other auto manufacturers, OEM Toyota/Lexus parts are very robust. They can & will last the lifetime of the vehicle. As for OEM vs aftermarket, 95% of the time, I stick with OEM & OEM family such as Denso, Aisin, etc. Electrical = 100% OEM/OEM family