FWIW, my buddy (the Toyota Master Tech) has been installing the URD circuits like crazy since I showed them to him - most everyone with aftermarket / high-flow cats were having issues, now none of us are.
P0420 and P0430 - 2006 LC (4 Viewers)
- Thread starter Colorado80
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The cat efficiency test runs on a 2 drive cycle schedule. In other words, every other time the car is driven. Just so you know.
To be very clear, DTC was not trigger yet but I was checking on OBD2 and saw the two codes pending when I was driving.
I also noticed the pending code would clear and come back to pending very often.
I also noticed the pending code would clear and come back to pending very often.
Voltage is not right. Will put back the old one.
Swapped the front one with old ones.
So now, A/F is old one and the back o2 sensors are new with denso.
Will report back if any codes triggered.
Do I need to disconnect the battery after installing sensors or reset with obd2 would do the trick?
Does anyone know how many on/off cycles
Will adjust to the new ones?
Am asking cuz I saw pending codes after installing the old (p2195) and reset it again.
Now if I should have codes, I would get the p0430 unless the new o2 sensors do the trick.
So now, A/F is old one and the back o2 sensors are new with denso.
Will report back if any codes triggered.
Do I need to disconnect the battery after installing sensors or reset with obd2 would do the trick?
Does anyone know how many on/off cycles
Will adjust to the new ones?
Am asking cuz I saw pending codes after installing the old (p2195) and reset it again.
Now if I should have codes, I would get the p0430 unless the new o2 sensors do the trick.
I have driven my LX for 300 +\- with no codes pending or trigging.
Hope it stays this way
Hope it stays this way
it looks like the rear O2 Sensors did the trick
no code for 3 weeks now
no code for 3 weeks now
I bought a 2005 LC 2 months back and after 200 miles my P0430 code went off. I did the typical cheap fixes at first:
- New Toyota Gas cap
- Cleaned MAF
- Air Filter
I've heard but not seen 05 built between May and June 05 are VVti engine. Do you have the VVti engine?
Hi 2001LC, My LC has a date of 08/04 on it. So i don't think i am within that window for the VVti engine.
Shortly after purchasing my 2003 LC I got both the P0420 and P0430 codes at 165K miles. Cleared and came back several times. Replaced both downstream sensors with Denso from Amazon, no more issues. Until when recently I rolled over 200K miles, got a P0420. Cleared it, then a hundred miles later got a P0430. Weird that they would both last exactly 35K miles. I'm currently in South America and don't feel like working on it here, planning to replace both again when I get back to the US.
Chicago - Deadhorse AK - Ushuaia - Montevideo, 19 months.
Just checked it into the port in Montevideo last Friday, shipping in a container back to Miami FL. Takes 30 days so I'm just hanging out in Buenos Aires enjoying the summer.
2007 - *think* I fixed it. Reporting back here. I was consistently getting P0420 and P0430 codes. At least one time per tank of gas. Sometimes the codes would come in together and sometimes I’d get them separately. I would clear them and then watch them for any other symptoms.
Here’s what I did (in this order, checking each time for codes coming back).
1) cleaned MAF (did not see any visual dirt, water spots - but probably had never been cleaned before)
2) replaced air filter (was a little dusty but not bad)
3) replaced gas cap (I may have broken one of the white plastic pieces in the cap, not sure)
4) put in BG 44K to clean fuel system
* after all of these “cheap” fixes I was still getting both codes
5) installed downstream O2 sensor - codes/CEL did not clear on their own, so I cleared and they have not been back in ~500 miles of driving and 2 fill ups.
6) I went ahead and changed the upstream O2 sensors because I had them ordered and we are all OCD like that
The advice has been given here already, but if I had to do it all over again, I’d jump straight to replacing the O2 sensors (downstream first).
If had not fixed with O2, I would have done fuel pump/filter next, then a full Cat replacement (not sure if would have tried aftermarket or not to save $$).
Here are pics of the old downstream O2 sensors.
Here are the old upstream O2 sensors.
As you can see, the upstream were in better shape. Not sure if I needed to change them or not, but I did.
I'll chime in...
Last July I got my first 420/430 codes on a trip from PA to North Carolina. I attribute this to a high elevation, they would go on/off intermittently themselves as elevation changed and upon returning home they cleared themselves.
They continued to show up intermittently, usually after or during short drives around town. Long highway hauls, or towing a trailer must have generated enough heat to get a valid reading. I cleaned the MAF and replaced my fuel filter but that seemed to have no real effect.
A month ago I had to do something because my CEL was on full-time and I was up for inspection.
Since some people recommended doing the front sensors first that is what I did. I cleared the codes manually and they were right back on my second drive. So I crossed my fingers and ordered the rears. Cleared the codes again and they've been off after many drives and about 300 miles. I think I'm in the clear!
So, +1 for doing the rear sensors first. They're also a lot easier to swap out.
But I figure I did some PM and have the old front ones as spares now.
Last July I got my first 420/430 codes on a trip from PA to North Carolina. I attribute this to a high elevation, they would go on/off intermittently themselves as elevation changed and upon returning home they cleared themselves.
They continued to show up intermittently, usually after or during short drives around town. Long highway hauls, or towing a trailer must have generated enough heat to get a valid reading. I cleaned the MAF and replaced my fuel filter but that seemed to have no real effect.
A month ago I had to do something because my CEL was on full-time and I was up for inspection.
Since some people recommended doing the front sensors first that is what I did. I cleared the codes manually and they were right back on my second drive. So I crossed my fingers and ordered the rears. Cleared the codes again and they've been off after many drives and about 300 miles. I think I'm in the clear!
So, +1 for doing the rear sensors first. They're also a lot easier to swap out.
But I figure I did some PM and have the old front ones as spares now.
