Re: Check Engine light - code P0420

On Dec 2, 12:10 pm, Mark <muff...@xxxxxxxxxxx> wrote:
I have a '97 Lexus ES300 and got a check engine light 2 days ago. I
got it checked and it comes up with a P0420 code. The code description
says "Catalyst System Efficiency Below Threshold (Bank 1)".

As I understand, it could be due to a defective catalytic converter,
damaged O2 ensors, contamination of converter due to incorrect
sealant, fuel, or fuel additive.

I had 2 repairs/services done on my car in the past 6 weeks:

1) I had replaced the flex pipe and the catalytic converter about 6
weeks ago. The flex pipe was leaking and the exhaust was making a lot
of noise. My mechanic advised that I also replace the cat. I got the
aftermarket (generic) flex pipe and cat.

2) I had a service done a week ago. I got the transmission liquid
flushed, radiator coolant flushed and fuel injection service done.

My guess is I am getting this code due to something gone wrong in
either of the above 2 repairs/services. The most obvious cause would
seem to be the first one, but I don't know if I can rule out the
second one as that was the most recent one ( a week ago).

I would appreciate if someone could help me with this. Could the
second service cause P0420 to be set? Or is it possible that I just
got a bad converter in repair 1? If yes, then would it take upto 6
weeks for the code to be set?

Any additional advice or suggestions would be appreciated.

Thanks,
Mark

========
========

Go BACK to the shop that did the FLUSH's......

explain that the light came on jest after getting the injector
flush service and ask them to PULL the codes AGAIN......
AND please CLEAR the codes so you can see IF they come
back, or better, how quickly they may comeback. Have them
MONITOR the Oxygen sensors DURING a TEST DRIVE!!
See if the sensors are reacting quickly, crisply, and changing
under various fuel demands. (heavy acell...cruise...decell from
cruising speeds)

Make sure they check HISTORY and PENDING codes while
they're doing this. These codes, if any, help in the diagnostic
process.

IF......the codes reset...or if the shop gives you a bit more info
to go on.....do a repost with ALL they're findings and let's take
a stab it.

However....if you feel yer lible to be anass to them...git high
tempered
easy..maybe gonna chewsomeass over they're service that caused
yer light to come on..............so that they charge you fer a
service
that they'de otherwise be more than likely to offer for free to
someone
that MITE spend more money with them......
then in that case.......

let's guess and save you and them all the heartache aye....

:)


the Fuel System service caused the light to come on.........

the Fuel mixture is now rich...

the injectors were cleaned and now one or more is NOT sealing or
the service mucked up either the front or rear sensor on that bank.


jest a guess......

:)


~:~
MarshMonster
~takes a toke......sorts his seeds.......no need in guess'n
if next years crop is a good one~
~:~
.

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