Autozone let me use their scanner. It showed code PO420. They said it could be the O2 sensor or catalytic converter or even a vacuum leak. The O2 sensor is $108.00. I hate to replace the O2 sensor and find out it's the converter. Also there are two O2 sensors. One before the converter and one after. Any suggestions?
2007-07-26 16:43:08 · 6 answers · asked by S R 3 in Cars & Transportation ➔ Maintenance & Repairs
you have one other option on it ,take it to a repair shop,and let them drill a hole in the converter and check the back pressure on it,and if its ok,then you,ll have to replace the 0-2 sensor on it,which one,is hard to determine,i usually replace the top one first,i have been real lucky with hitting it right on those,good luck on it.
2007-07-26 16:49:30 · answer #1 · answered by dodge man 7 · 0⤊ 0⤋
Using a volt meter or an oscillioscope, measure the voltage output of both O2 sensors. If they are not very nearly the same, then one of them is damaged. I believe 1 volt is a normal reading. The oscillioscope would show a better wave form. Also, you can take the O2 sensor out and measure it on the bench using a propane torch. Again, the sensors should give the same reading.
Beware, the new 07 camry uses 2 senors, but one is an O2 sensor and the other is a fuel/air ratio sensor. The difference is in the linearity of the output signal.. hence if your O2 sensors have different part numbers, don't expect identical results.
2007-07-30 15:30:59 · answer #2 · answered by Josh B 4 · 0⤊ 0⤋
Some check engine lights come on at 90k miles, even if everything is working correctly. Then you take it into the shop and they reset it and charge you.
My Ford F-150 check engine light comes on sometimes. I got worried about it until I found out that air conditioning condensation drips down onto an O2 sensor and causes an error code. This apparently happens only with the 97 model.
2007-07-26 16:51:10 · answer #3 · answered by plezurgui 6 · 0⤊ 0⤋
p0420 catalyst system efficiency, bank1, below threshold, basically means that the catalyst is not working as well as it was intended. the CPU sees that the signal on the o2 sensor after the cat is showing too much activity, very close to the one before the cat. see if you cant find some one to do a catalyst efficiency test, see if it is doing any thing
2007-07-26 17:26:40 · answer #4 · answered by mdk68gto, ase certified m tech 7 · 0⤊ 0⤋
yes is the car running properly?? if it is you can wait a while if you dont want to wait go to the mechnic and have him put the muffler sniffer in and put it on the smog machine it will tell you if it is the cat or not usually the cat if it is bad will make your car smell like rotten eggs honest. its about time for a change but if its good then have him test the o2.
personally i wouldnt do a thing if it is running good have the mechanic turn the light off and see what happens
2007-07-26 16:53:32 · answer #5 · answered by bone g 3 · 0⤊ 0⤋
That sounds like an original Toyota part and install cost. Go to your local muffler shop. They should be able to replace it with an aftermarket for less than $300.
2016-05-19 23:51:07 · answer #6 · answered by ? 3 · 0⤊ 0⤋