Got a CEL today

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06-09-2006, 11:41 AM
riverracer

Got a CEL today

The cel came on today so I stopped at Vatozone and had it checked.
Got the P0420 code
Their print out says"The Pcm has determined that the catalyst system efficency for bank 1 is below threshold for the current engine operating conditions. (Bank 1 identifies the location of cylinder #1, While Bank 2 identifies cylinders on the oposite bank)"

The cat is almost new so could it be an o2 sensor? If so How do I tell which one it is? If it's something else I would be very greatful for your help or comments.
Jerry
06-09-2006, 11:50 AM
Titus

Quote:

Originally Posted by riverracer

The cel came on today so I stopped at Vatozone and had it checked.
Got the P0420 code
Their print out says"The Pcm has determined that the catalyst system efficency for bank 1 is below threshold for the current engine operating conditions. (Bank 1 identifies the location of cylinder #1, While Bank 2 identifies cylinders on the oposite bank)"

The cat is almost new so could it be an o2 sensor? If so How do I tell which one it is? If it's something else I would be very greatful for you help or comments.
Jerry

How many miles do you have? If under 80k (or around there) Mazda must replace any faulty smog equipment, which should include both the O2 and the cat.
06-09-2006, 11:52 AM
riverracer

86000 and they replaced the cat right after I bought the car:(
06-09-2006, 11:56 AM
Billy Blaze

Bummer, hope you can get it figured out quick Jerry.
06-09-2006, 11:57 AM
Titus

Quote:

Originally Posted by riverracer

86000 and they replaced the cat right after I bought the car:(

:punchout:

Well, hell if I know... I have an NA. If you don't get any experienced responses, I say try seafoaming it. It's almost as good as duct tape. Got a CEL, Seafoam. Losing power, Seafoam. Aching back, Seafoam. Wife left you, Seafoam. ::Clown::
06-09-2006, 12:02 PM
riverracer

Quote:

Originally Posted by Titus

:punchout:

Well, hell if I know... I have an NA. If you don't get any experienced responses, I say try seafoaming it. It's almost as good as duct tape. Got a CEL, Seafoam. Losing power, Seafoam. Aching back, Seafoam. Wife left you, Seafoam. ::Clown::

Ok...I know this has probably been explained here a 1000 times butt....
Where do I buy the Seafoam and what do I do?::OldMan::

If the Seafoam brings my wife back I'd just as soon drive with the CEL on.......
06-09-2006, 12:07 PM
Titus

Quote:

Originally Posted by riverracer

Ok...I know this has probably been explained here a 1000 times butt....
Where do I buy the Seafoam and what do I do?::OldMan::

If the Seafoam bring my wife back I'd just as oon drive with the CEL on.......

OK... Gary sells it, and so do some NHPSs. For what it does, go HERE. For how, hook some vacuum hose to the nipple on the intake manifold for the cruise control and stick the other end into the can. Have some one modulate the throttle to keep it from stalling as it sucks it all in. Just before it is all in, let the engine stall out. Let it sit for a few hours and then drive the piss out of it. Note: MUCH smoke will be produced. Your neighbors will think your house is on fire, and everyone withing 10 blocks will see the cloud, so it is advised to do it at night.
06-09-2006, 12:08 PM
onething

Quote:

Originally Posted by riverracer

If the Seafoam brings my wife back I'd just as soon drive with the CEL on.......

:cat:

You want the car fixed or not?::Clown::
06-09-2006, 12:23 PM
sammm

Quote:

Originally Posted by riverracer

Where do I buy the Seafoam

O'Reilly's carries it...there's one not far from onething's place on 303.
06-09-2006, 12:45 PM
tailchaser

vatozone carries it now, too... and it's cheaper.

I'd guess O2 sensor, myself, though, since that's what the PCM uses to determine catalyst efficiency...
06-09-2006, 12:53 PM
riverracer

Quote:

Originally Posted by Titus

Ahh, but will the guy at the counter sell it to you if his computer doesn't list it as working with a Miata? :rolleyes:

Good point Titus....I got it a O'Reilly's::Clown::
06-09-2006, 04:00 PM
Sharpie

I'm with TC, I'd do the o2 sensor.
06-09-2006, 04:05 PM
Titus

Quote:

Originally Posted by Sharpie

I'm with TC, I'd do the o2 sensor.

Is that O2 Sensors on NBs, or is that only the later ones?
06-09-2006, 04:08 PM
riverracer

Quote:

Originally Posted by Titus

Is that O2 Sensors on NBs, or is that only the later ones?

There's 2 from what vato told me down at the zone::Clown::
I think one is by the cat and the other one is?????????
Any TCB places to get them?
I know there not cheap.
06-09-2006, 04:27 PM
HudsonHawk

There is probably a pre and post cat sensor.
06-09-2006, 04:35 PM
riverracer

Quote:

Originally Posted by HudsonHawk

There is probably a pre and post cat sensor.

I found some here
http://replacement.autopartswarehous...Sensor&dp=true
I'm gonna do the seafoam first. Should I get them both or just the post cat first?:D
06-09-2006, 05:19 PM
sammm

I'd try the seafoam first. Clean the intake and throttle-body second. Replace O2 sensors last. (First two are cheap fixes and it cured my P0420)
06-09-2006, 06:01 PM
riverracer

Thats the plan Sammm...Do I need to take the throttle-body apart to clean it?
06-09-2006, 06:17 PM
sammm

Quote:

Originally Posted by riverracer

Do I need to take the throttle-body apart to clean it?

Only if you want to do it correctly. :rolleyes: (Yes, it's well worth it) Remember to buy Throttle-Body cleaner (2 cans), not Carb cleaner.

http://www.miata.net/garage/manifold/index.html
06-09-2006, 08:37 PM
Majik

There are two O2 sensors on OBD2 cars. One in front of the cat takes a reading and helps determine the fuel mixture. The second takes a reading and makes sure that there is enough difference from the first reading to make sure the cat is working. If the cat is new this most likely the issue. There are two kinds of replacements. OEM and generic. Both work the same, the difference is in installation. OEM has the OEM plug that takes about 15 minutes to replace from jacking the car up to back down again. THe other is going to require some soldering. For the price difference I would do the generic bosch. I think it is 75 while the OEM is around 2 bills.
06-09-2006, 09:35 PM
RX7-2nr

hmm im gonna try Seafoam on my car. my car runs rough, idles rough, stalls, surges, and many more assorted probs.
06-09-2006, 10:25 PM
Titus

Quote:

Originally Posted by Majik

There are two O2 sensors on OBD2 cars. One in front of the cat takes a reading and helps determine the fuel mixture. The second takes a reading and makes sure that there is enough difference from the first reading to make sure the cat is working. If the cat is new this most likely the issue. There are two kinds of replacements. OEM and generic. Both work the same, the difference is in installation. OEM has the OEM plug that takes about 15 minutes to replace from jacking the car up to back down again. THe other is going to require some soldering. For the price difference I would do the generic bosch. I think it is 75 while the OEM is around 2 bills.

To add to this, it is interesting to note that the cheap universal Bosch sensor does have a plug on the end, it just doesn't match the plug on the car. The plug does match several late 80's early 90's American cars. If you search miata.net, you will find a list of cars. Many go grab a few of the plugs off cars from the junkyard, and then cut the miata plug off of the old OEM O2. You can then wire up the plug from the bad sensor in your car to the junkyard plug that matches the universal sensor to make an adapter. You then have plug and play for OEM and Universal next time you need to swap one. Seems like a lot of work to me, but if you are already going to the junkyard for something, it might be worth while.
06-09-2006, 10:44 PM
Sharpie

Quote:

Originally Posted by Titus

To add to this, it is interesting to note that the cheap universal Bosch sensor does have a plug on the end, it just doesn't match the plug on the car. The plug does match several late 80's early 90's American cars. If you search miata.net, you will find a list of cars. Many go grab a few of the plugs off cars from the junkyard, and then cut the miata plug off of the old OEM O2. You can then wire up the plug from the bad sensor in your car to the junkyard plug that matches the universal sensor to make an adapter. You then have plug and play for OEM and Universal next time you need to swap one. Seems like a lot of work to me, but if you are already going to the junkyard for something, it might be worth while.

I did that for mine when I did the new o2 sensor for the FM2. It came off a late 80's mopar sedan.

I've helped a guy replace both, crimping and connecting wires, not fun under the car. Try the Seafoam, it worked for Samm.
06-09-2006, 11:53 PM
riverracer

Thanks for al the input guys. The plan is to do the Seafoam next Saturday morning. This weekend is booked for me.
Jerry:D
06-10-2006, 09:07 AM
Billy Blaze

Hey Jerry if you do it on a Sunday I will meet up with you and help you.
06-10-2006, 10:06 AM
pliablemoose

Quote:

Originally Posted by riverracer

If the Seafoam brings my wife back I'd just as soon drive with the CEL on.......

LOL, guess I'm not gonna use seafoam after all either ::Curls::
06-17-2006, 07:36 PM
POS Racing

Well riverracer other that blowin a lot of smoke today any thing chage??? ;-)
06-17-2006, 08:36 PM
riverracer

Quote:

Originally Posted by POS Racing

Well riverracer other that blowin a lot of smoke today any thing chage??? ;-)

No not yet...I drove it hard at highway speeds for about thirty minutes after we finished. Light was still on.....So I came home and let it cool...then disconnected the battery and I have driven it 3 times since then and the light is still out...I'm going to drive it alot this week and keep you posted...Thanks again for the help:D
06-18-2006, 07:00 PM
riverracer

Ok guys...here's the latest on my P0420 code problem....The ::Censor:: light still comes on. Looks like the intake will have to be cracked...:(
06-18-2006, 07:23 PM
pliablemoose

http://www.obd-codes.com/trouble_cod...old-bank-1.php
06-18-2006, 07:45 PM
riverracer

Quote:

Originally Posted by pliablemoose

http://www.obd-codes.com/trouble_cod...old-bank-1.php

Thanks for the link....
Ok guys what would you do first?
06-18-2006, 08:51 PM
pliablemoose

Quote:

Next step is to measure the voltage at the oxygen sensor on Bank 1 (the rear sensor, or the sensor after the converter). The voltage should be low and steady (~200mV, depends on the vehicle). If the voltage varies (e.g. 100mV to 600mV) then it's time to replace the catalytic converter. In fact, it would be a good idea to test each oxygen O2 sensor while you're at it.

Looks like that's the next step, the one after that looks pretty expensive :(