I knew that theres a potential problem with using an aftermarket af so given my Calif emissions 4 cyl I purchased the af straight from my toyota shop. Then I blew a rear spark plug. This code does not cause drivability issues unless the Cat is clogged. On toyota code p0420 is almost always a bad cat. If you suspect that the check valve is allowing exhaust to flow backwards, remove it and blow through both ends. If it does, then the O2 sensor is bad.
If your engine has air injection, disconnect the check valve from the distribution manifold, and connect a low pressure gauge. How can I tell if my catalytic converter is working properly? The same goes for worn or damaged rings or cylinders. Make sure there are no obvious exhaust leaks first. . But, after a few second the light came back on. Aug 24, 2009 B2796 is no communication in Immobiliser system, which means you or some one else try to use a key transponder to start the car.
Restrictions may apply in other states. I would say that this shows that my sensors are good and my cat is bad. Now, I'm not completely sure which sensor this is, but I think it's the front one: I unplugged the front o2 sensor halfway through that reading and the line went completely flat. If an O2 heater was bad it would set a different code. I have an Actron code reader.
It should be routing air to the converter when the engine is at normal temperature. There are ways to trick the rear O2 into not throwing this code, but they are illegal. My intro into this site was prompted by the p0420 on my 2000 camry 4cyl. May 19, 2009 P0420 indicates you have a catalyst efficiency issue; replacement of the Air-Fuel Sensor should take care of that; The P0441, P0446 and I assume P0440 ; you said 446 twice, indicates a faulty or loose fuel cap; it is not sealing properly. The buildup of backpressure will cause a drastic drop in engine performance and fuel economy, and may even cause the engine to stall after it starts if the blockage is severe.
Just because a converter is passing gas doesn't mean it is okay. Ive checked twice and its p0420 - Catalyst System Efficiency Below Threshold. Some models barely have any temp difference from inlet to outlet. I should mention here that the converter seems to have heat discoloration, which seems to indicate to me that there's too much fuel in the exhaust? Thanks This ad is not displayed to registered members. I had replaced the second catalytic converter which includes the flex pipe and the code popped up about a month or 2 later.
A FixYa rating from you regarding my assistance would be greatly appreciated. Most repairs have already been covered multiple times somewhere in great depth that will satisfy your needs. Im hesitant to replace toyota has a service bulletin on this code see link below httptownhall-talk. If the your converter is plugged, it will create a restriction in your exhaust system. I figure it cost me about 2k on the trade.
If it does, then the O2 sensor is bad. I took it AutoZone and theypulled the p0420 code from it. Please or to join the conversation. Any competent shop can repair the car not just toyota dealer. Also respect those that take the time to answer questions and remember that many are professional mechanics, who normally get paid very well to diagnose automotive repairs. I filled the tank after driving about a hundred miles. R All things being equal the p0420 code is typically a bad converter.
Failed coolant temp sensor for the engines computer. My daughter messed up my mpg calculations by adding 20 in gas between my fill-ups. If the heater portion of the sensor is not working, the cat efficiency code may recur even though the rest of the O2 sensor is functioning properly. I then thought that maybe one of the oxygen sensors is bad. When is the code detected? By making a good attempt to narrow down where and what may be causing the problem you save those trying to help many steps in diagnosing the problem. Connect the gauge to a source of intake vacuum on the intake manifold, carburetor or throttle body. It sounds fine the wiring is fine on the O2 sensors, and the car runs like the first day i drove it.
Two of the wires are for element and another two for sensor. Without further diagnositics would be just guessing. The toyota Just replaced and fixed related codes for airfuel sensor on 2000 camry 4 cylinder. But it might not be the sensor's fault. The car has 95K miles on it.