Mechanics ripping me off ...Plzzz help ! - Toyota Nation Forum : Toyota Car and Truck Forums

vikingz999 · 05-04-2009, 09:45 PM

Hello Experts,
I hope this post finds you all in the best of your health.!

I have an issue with my 2001 Camry i4 and I am sure you folks have probably seen it a lot.

Its a check Engine Light and the Error code is P0420.

I got the error code and it talks about Catalytic converter ...low efficiency....something ( i dont remember the whole description)

But.... i have had mechanics change the smaller catalytic converter twice...its goes away for 300 miles and then come back when its raining / just finished raining and its all wet on the road....... or its pretty humid. I see the engine rev up a very tiny bit.

But the issue is i have had 2 mechanics do the same thing and the darn light keeps coming back. I dont know what to do and where to do....honestly i am kind of financially struggling so dealership would be a bit harder option.

Please suggest whats wrong...!

Thanks.

Vikingz

***MR2Jedi*** · 05-05-2009, 01:01 AM

Hey Vikingz, I moved your thread from the intro section to this Camry forum.These guys can help you.
Good Luck and Welcome to ToyotaNation

Stillrunning · 05-05-2009, 05:21 AM

http://www.obd-codes.com/forums/view...php?f=1&t=4801

Looks like similar problem except for the rain thing.

More P0420 Toyota code info: http://www.obd-codes.com/forums/view...php?f=6&t=4255

The rain may be shorting out the O2 sensor wiring causing a false code trip?? Two bad CATS (if new) in a row is remote.

***ASG14*** · 05-05-2009, 06:27 AM

I'd say the same as stillrunning ^.

P0420
Catalyst System Efficiency
Below Threshold
(Except California Spec.)
Three–way catalytic converter
Open or short in heated oxygen sensor circuit
Heated oxygen sensor

P0420
Catalyst System Efficiency
Below Threshold
(Only for California Spec.)
Three–way catalystic converter
Open short in heated oxygen sensor (bank 1 sensor 2) circuit
Heated oxygen sensor (bank 1 sensor 2)
Open or short in A/F sensor circuit
A/F sensor

jmborchers · 05-05-2009, 08:39 AM

The mechanic needs to pull the engine freeze frame data with the code to understand what is occuring.

hill8570 · 05-05-2009, 10:41 AM

The oxygen sensor downstream (closer to the tailpipe) of the catalytic converter is used to monitor the efficiency of the cat. Two bad cats in a row are unlikely, and the correlation with rain makes it most likely a wiring issue -- probably a connector or connector boot that's letting in water. Since the farking downstream O2 sensor is under the car (between the cat and the muffler), and is routed to the engine compartment in the most bizarre way possible, it's easy to see how that could happen. I'd check the wiring and connectors coming from the downstream O2 sensor. See http://www.camrystuff.com/manuals/Gen4/SFI.pdf starting on page 62 to get a decent idea of the area we're talking about (sensor 2 is always the downstream sensor, and the 4-banger only has one bank, so you're looking at Bank 1 Sensor 2).

sloanj1 · 05-05-2009, 02:49 PM

If the cats have been replaced with one of those cheap "one size fits all" cats, that can very well be the issue. Toyotas are very sensitive when is comes to emission controlling parts. Unfortunately the Toyota cat is very pricey. As for the rain affecting it, I would lean towards a wiring issue.

vikingz999 · 05-05-2009, 04:00 PM

Its not really the rain. Its the rainy season, all moist roads , humidity in the air with wet roads ( kind of like ..how you roads look like with water on them after rain).
Do you think that would have caused the issue?

The first time it came on was in Arizona super hot dry....(I replaced the smaller cat after an accident...the catalytic converter started clanking and banging...so the dude said replace it...after 300 miles o the arizona highway Santa gave me a visit.....SURPRISE !!!!!!!!!!!! CEL-P0420 !!!!!!!!

I love my car..never stood me up.. but this orange colored devail makes my heart break !!!!

SexieWASD · 05-05-2009, 04:29 PM

Has the second O2 sensor been replaced? Perhaps the first mechanic destroyed it when replacing the cat, and replaced it with a cheap one to save money. Those cheap O2 sensors will usually throw a cat efficiency code on Toyotas.

vikingz999 · 05-05-2009, 04:49 PM

Oh yes I forgot to mention:
The car has 71,000 miles on it.
Also the previous 2 cats (smaller one) under the car ( not the one closest to engine) were cheap ones. Cuz the mechanic only charged me 75 bucks for everytime.

vikingz999 · 05-05-2009, 04:51 PM

SexieWASD,
I dont think he replaced the second O2 sensor.
Maybe messed it up but i dont think he changed it.
Because he didnt mention changing the sensor or else he would have charged me for that one too.

sloanj1 · 05-06-2009, 02:35 PM

Check the rear O2 sensor/wiring. But if the cats were cheapys, that can definitely cause an issue.

ghettosled · 05-06-2009, 06:58 PM

i dont know how the cat(s) are monitored on an '01 i4 camry, but on my '96 i4 camry there are two cats and only the primary (large one by the engine) is monitored. when i got the 0420 light, i could change the second one all day and it wont make a difference until i changed the primary cat. FWIW.

SexieWASD · 05-07-2009, 06:50 AM

Now that you mention it I think your right, I'm too lazy to double check, but I think only the main cat is monitored.

project92camry · 05-07-2009, 10:35 AM

ur cat is not the problem. it has to be the o2 sensor. check the wires if the wires seem fine i would take the sensor out and see if the mechanic got any anti seize on the tip. if theres sumthing wrong wit the sensor always get OEM o2 sensors. never get universal, they always give cars problems and are not reliable.