[*67firebird*]

read my code and its a Po139, says its bank 1 sensor 2. i can only find 2 sensors and the second one seems to be behind the CAT. and it cost $336 to replace by myself. what can i do anyone ever worked on one?

[LPete]

Bank one sensor two IS the one behind the cat. Be careful -- codes don't automatically mean bad parts. You'd be taking a chance replacing it without some testing.

I'll look in AllData tomorrow and try to give you some troubleshooting hints.

[bren566]

That seems expensive for an O2 sensor. Are you sure it's not an air/fuel monitor? They usually cost alot more and the foreign cars love to use them. If it is, don't put an O2 in its place or it will all sorts of codes. Good luck!

[*67firebird*]

if its after the CAT, doesnt it just read the emission levels? the first one reads A/F right?

[LPete]

Its main function is to make sure the catalyst is working. Some cars use it to fine-tune the fuel mixture.

Some late model Hondas had catalyst problems, but I'm pretty sure they usually set a catalyst code.

[goquick]

My neighbor wouldn't/ couldn't understand that hondas break just like any other type car.

Ok, getting more serious, Did it throw an egr/emissions code at all? Also a weak spark plug wire or plug might make it think there is a problem with the sensor.

[*67firebird*]

well the code was P0139 which is Slow response from sensor, there is no difference in the way it drives so i figure it doesn't have a misfire problem or fuel issue..... i will check the plugs but i doubt its the problem because it doesnt lag or anything.

then again im just learning this hole computerized engine thing.

[dreamingmuscle]

If it's running ok. Get the codes cleared and see if they come up again. Might have been just a burp in the system and means nothing.


Glen

[LPete]

The diagnostic chart shows to speed the engine up to 3000 RPM 'til the fan comes on, then check the rear O2 sensor output. If it's between .3 and .8 V, replace the sensor. If it's not, the problem is intermittent and could be loose connections or wiring between the sensor and PCM (or a bad PCM). I agree with dreamingmuscle, clear the code and see what happens.

There's one engine (the D17A6) that has three sensors, and Honda requires that the two rear ones be replaced together. The engine model I believe is stamped on the front side of the engine, possibly near the bellhousing flange. I think it's easy to see from the front of the car.

[*67firebird*]

I have a D17A1 type. ill have to check the voltage the. hopefully its the sensor. thanks LPETE. OZ

[rustedgoat]

Heres a good site for Honda parts. They show list price and then their discounted price. I use it for printing out the diagrams from the parts book

http://www.hondaautomotiveparts.com/home.htm