I have a 2002 Toyota Camry 2.4l that has a p0420 code. Trying to confirm whether it's a bad catalytic converter or not. The readings for the o2 sensors are at 2500 rpm o2s11 between .56 and .66v; o2s12 between 3.2 and 3.3v. They seem to fluctuate together. I did test the temp before and after cat and it seems to be 370 before 200 after. Thanks in advance. Brian.
P0420 Toyota Camry
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P0420 almost always indicated a bad cat. That said, you should replace the oxygen sensors along with it.
Yep bad cat and o2 should be replaced together
Unfortunately you'll have to replace the cat. I too had that code last year.
If it's possible, I recommend using a universal magnaflow cat since you're in TX. I replaced mine with one a little over a year ago in my Toyota and it's working fine. I also replaced both my O2's and used Denso.
If it's possible, I recommend using a universal magnaflow cat since you're in TX. I replaced mine with one a little over a year ago in my Toyota and it's working fine. I also replaced both my O2's and used Denso.
Thanks everyone. I suspected I needed anew cat but wanted to make sure before I went ahead and replaced it. Appreciate the help. Happy new year! Brian
You don't need a "CARB" cat even if you have a "California Emissions" car unless you live in CA. Don't let NAPA sell you a "Carb approved" unit for 650 bucks when Rock Auto had the 49 state for less than 200. When the manifold and after cat sensors begin to track each other it means the cat isn't doing much, if anything.
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Originally Posted By: Briangillen
I did test the temp before and after cat and it seems to be 370 before 200 after.
Not catalytic action is taking place, after should be hotter. You can always install one of these in the rear 02 bung then the 02 into it, no more P420
http://www.ebay.com/sch/i.html?_from=R40...er&_sacat=0
I did test the temp before and after cat and it seems to be 370 before 200 after.
Not catalytic action is taking place, after should be hotter. You can always install one of these in the rear 02 bung then the 02 into it, no more P420
http://www.ebay.com/sch/i.html?_from=R40...er&_sacat=0
Originally Posted By: Briangillen
I have a 2002 Toyota Camry 2.4l that has a p0420 code. Trying to confirm whether it's a bad catalytic converter or not.
It's pretty much certainly the cat, especially if the vehicle has been driven repeatedly with a fuel-level below 1/4 tank.
Large leaks in the exhaust either before or after the cat can also trigger a P0420.
There can occasonally be other factors involved, such as abraded wires or defective ignition modules, but these tend to be systemic and are eventually covered under TSBs issued by Toyota; you would have to check http://www.techinfo.toyota.com/ to see if there are any for your vehicle. Techinfo is something like $20 for two days of all-you-can-eat.
I have a 2002 Toyota Camry 2.4l that has a p0420 code. Trying to confirm whether it's a bad catalytic converter or not.
It's pretty much certainly the cat, especially if the vehicle has been driven repeatedly with a fuel-level below 1/4 tank.
Large leaks in the exhaust either before or after the cat can also trigger a P0420.
There can occasonally be other factors involved, such as abraded wires or defective ignition modules, but these tend to be systemic and are eventually covered under TSBs issued by Toyota; you would have to check http://www.techinfo.toyota.com/ to see if there are any for your vehicle. Techinfo is something like $20 for two days of all-you-can-eat.
Originally Posted By: Trav
Originally Posted By: Briangillen
I did test the temp before and after cat and it seems to be 370 before 200 after.
Not catalytic action is taking place, after should be hotter. You can always install one of these in the rear 02 bung then the 02 into it, no more P420
http://www.ebay.com/sch/i.html?_from=R40...er&_sacat=0
Spacers work by placing the tip of the O2 sensor out and away from the exhaust stream and into a little pocket where the level is lower and doesn't change much, which the ECU sees as the cat reacting properly to everything going into it. The right angle one, in particular, may be too obvious to smog inspections if they bestir themselves to look under the car. Ask around your area before installing one.
Originally Posted By: Briangillen
I did test the temp before and after cat and it seems to be 370 before 200 after.
Not catalytic action is taking place, after should be hotter. You can always install one of these in the rear 02 bung then the 02 into it, no more P420
http://www.ebay.com/sch/i.html?_from=R40...er&_sacat=0
Spacers work by placing the tip of the O2 sensor out and away from the exhaust stream and into a little pocket where the level is lower and doesn't change much, which the ECU sees as the cat reacting properly to everything going into it. The right angle one, in particular, may be too obvious to smog inspections if they bestir themselves to look under the car. Ask around your area before installing one.
In MA they don't even check. No codes and its good to go, maybe TX is the same?
Now in MA 2001 cars are emissions exempt anyway.
Now in MA 2001 cars are emissions exempt anyway.
Originally Posted By: Trav
In MA they don't even check. No codes and its good to go, maybe TX is the same?
Now in MA 2001 cars are emissions exempt anyway.
His is an '02, and he's in Texas. I know about Massachusetts, first hand.
In MA they don't even check. No codes and its good to go, maybe TX is the same?
Now in MA 2001 cars are emissions exempt anyway.
His is an '02, and he's in Texas. I know about Massachusetts, first hand.
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It's pretty much certainly the cat, especially if the vehicle has been driven repeatedly with a fuel-level below 1/4 tank.
What is the reasoning behind this?
It's pretty much certainly the cat, especially if the vehicle has been driven repeatedly with a fuel-level below 1/4 tank.
What is the reasoning behind this?
It would be a good idea to verify power and ground going to the rear oxygen sensor before replacing the catalytic converter; wires aren't as tough as you guys think.
I have never tried this but for the cost of the cat and O2S Link on you tube
Originally Posted By: simple_gifts
Originally Posted By: Tegger
It's pretty much certainly the cat, especially if the vehicle has been driven repeatedly with a fuel-level below 1/4 tank.
What is the reasoning behind this?
Very low fuel results in intermittent starvation of the fuel pump, which in turn causes intermittent lean-misfires as fuel-pressure drops intermittently.
The misfires are not frequent enough for you or the ECM to feel (so no MIL), but they cause the cat's surface to overheat temporarily, which damages it. Over time the cat's surface erodes, reducing the cat's oxygen-storage capacity, and thus its life. It's a cumulative thing, much like smoking and emphysema.
At least some automakers put warnings in their Owner Manuals that proscribe driving around with low fuel levels, and this is why.
Originally Posted By: Tegger
It's pretty much certainly the cat, especially if the vehicle has been driven repeatedly with a fuel-level below 1/4 tank.
What is the reasoning behind this?
Very low fuel results in intermittent starvation of the fuel pump, which in turn causes intermittent lean-misfires as fuel-pressure drops intermittently.
The misfires are not frequent enough for you or the ECM to feel (so no MIL), but they cause the cat's surface to overheat temporarily, which damages it. Over time the cat's surface erodes, reducing the cat's oxygen-storage capacity, and thus its life. It's a cumulative thing, much like smoking and emphysema.
At least some automakers put warnings in their Owner Manuals that proscribe driving around with low fuel levels, and this is why.
Thanks for that Tegger.
I once parked my 92 lesabre on a downslope and the car wouldn't start when I got back to it... Not enough room to roll out of the spot as the car in front was too close. That is my < 1/4 tank avoidance impetus.
I once parked my 92 lesabre on a downslope and the car wouldn't start when I got back to it... Not enough room to roll out of the spot as the car in front was too close. That is my < 1/4 tank avoidance impetus.
The absolute worst thing is to be careless enough to allow the vehicle to run out of gas.
The process of running out of gas involves a prolonged period of lean misfires, which causes very heavy damage to the cat, and can reduce its life significantly.
The process of running out of gas involves a prolonged period of lean misfires, which causes very heavy damage to the cat, and can reduce its life significantly.
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