Has your ecm been re-programmed to get rid of the false cat threshold code known problem? Or is your cat really dying? Do some searches on here for that code and the ECM upgrade route.

Hacking the O2 sensor wires will kill the engine mpg performance, won't turn off the MIL light, might stop the car starting and could possibly actually damage the CAT, if you are the US it's probably ilegal to defeat the MIL/CAT emissions stuff as well.

 

My dealer replaced the ECM on my 2001 that was throwing that code 100% free, took a few hours at the dealer. It's considered a recall.

That said, if you want to go the MIL eliminator route, you need to install it on the SECOND o2 sensor, the one after the cat. There should be instructions available online with a google search.

They also sell physical MIL eliminators which don't require hacking the wires. Basically just a spacer that moves the 2nd O2 sensor further away. Completely reversible. Search ebay.

 

thanks for the help but i still need to try the mil

ive been to 2 dealers--same story, no good will, and a cost of $600-$2000 to replace the ECM. Im out of warrenty by 10K miles and they wont budge.

Yes i have done all the software updates over the cars life and the cat was replaced before i got the car, so really the only options are the MIL eliminator or a new ECM which i don't have the $$ to do.

It really irritates me that there is nothing technically wrong with the car--the ECM is just the old model for the 2001 and i only have 2 O2 sensors not 3 like the newer models--so basically the mil seems logical to try b/c of my situation. ill google more , but any help with the wiring diagram would be greatly appreciated or any pictures/tips.

thanks everyone you are lifesavers.

 

ive been to 2 dealers--same story, no good will, and a cost of $600-$2000 to replace the ECM. Im out of warrenty by 10K miles and they wont budge.

Yes i have done all the software updates over the cars life and the cat was replaced before i got the car, so really the only options are the MIL eliminator or a new ECM which i don't have the $$ to do.

It really irritates me that there is nothing technically wrong with the car--the ECM is just the old model for the 2001 and i only have 2 O2 sensors not 3 like the newer models--so basically the mil seems logical to try b/c of my situation. ill google more , but any help with the wiring diagram would be greatly appreciated or any pictures/tips.

thanks everyone you are lifesavers.

The PO420 issue has no limit on the deadline as it was listed as a recall issue. Mine produced this code back in late 2007 or early 2008 at or around 150k miles. The Honda dealership replaced the ecu with a flashable one and I haven't had a code since. There is a thread on this site with the related bulletin number.

 

I'm just curious. What is the car doing? Not running smoothly, not starting...

Or is it a light on the dash that goes on?

 

2 potential options, but be aware that neitehr fixes the emission issue:

DIY Mechanical O2 simulator - Honda Civic Forum

Making your own rear o2 bypass/simulator - DSM Forums

I have already made the circuit board option in anticipation of a turbo install, but haven't hooked it up to see if it will work on our cars.

mods: If this is against the forum rules please delete.

 

thanks for all the help, here is a bit more info

the service bulletin from 2007 is 07-038--but none of my dealers will honor it as a recall, instead it says the "normal warranty applies" and specifically the bulletin says

"Out of warranty: Any repair performed after warranty
expiration may be eligible for goodwill consideration by
the District Parts and Service Manager or your Zone
Office. You must request consideration, and get a
decision, before starting work."

and so far no goodwill from my dealers

So as for the ? about what are my symtoms--really i have no symptoms other than the check engine light comes on--which is again why this is such a pain and im hoping the MIL eliminator can correct this computer glitch b/c there is nothing technically wrong with the car, just the stupid ECM computer and only 2 O2 sensors..

so anyone have the wiring diagram for the O2 sensors on an 01 insight?

thanks a million

 

Just use the mechanical method using the spacers. It will work fine and is cheap.

Trying to fake the O2 sensor will be hard as it has heaters etc that the ECM monitors and will throw codes for.

 

http://www.paladinmicro.com/MustangMILEliminator.htm

Try a physical device first such as a spark plug spacer as others have mentioned

Here is the bulletin.
honda service bulletin 0420.pdf

 

Thanks ill let you know how it goes

ill try the spacers and let you all know how it goes.
thanks for all the help/advice---if you think of other fixes please let me know
have a great weekend

 

spark plug spacer worked!

thanks for the advice, i used 2 spark plug spacers stacked together 1st on o2 sensor above the cat (next to the engine) which held up for a while, then i sold the car and the new owner moved the spacers to the downstream o2 (below the cat) and it seems to be holding

thanks everyone.

take care
jb