CA->Fed VX conversion won't pass smog :(

[mango]

Ayudame with your knowledge, amigos!

I converted my 94 vx from CA to Fed in 7/08. To my surprise, the conversion went off without a hitch. I went from low to mid 40s to averaging 51mpg in my mostly city commute. (me=very happy). When I did the conversion, I made sure to shield the wiring. I also left the original 4 wire plug intact so I could switch back if need be.

In 10/09, it came time to get smogged again. I wasn't able to pass in Federal mode. It came down to crunch time, and I swapped the ECU and o2 sensor back to CA versions, and passed no problem. I love the mpgs of Fed mode, but don't want to be a gross polluter! Could you guys help me figure out what's going on?

Original test in Fed mode:


Tune up- cap, rotor, wires, plugs ZFR4F-11, air filter


Replaced Bosch L1H1 wideband o2 sensor with NTK L1H1 wideband o2 sensor. Ran tank very low then added a little 100 octane gas at Smog shop's recommendation.


Finally I ran out of time and put the old CA L01 ECU and 4 wire CA o2 back in and passed no problem


Subsequently, I checked my soldering/wiring, redid my ground with a nice gold ring term (not sure what it's called exactly), and tried an A00 ECU instead of A01. Just by giving it the sniff test, I can't say I've noticed any improvement in Fed mode emissions.

My only small suspicion is that there is about an inch of exposed wiring without shielding at both ends of where I did the new wiring. Could that be enough to mess me up? Lean burn mode is still working very well; I notice with pedal feedback and acceleration and also by my mpguino.

The car has 220K miles on it, but runs really really well. There is not suspicious behavior with the car that would make me suspect any problems had I not failed smog.

Also, does anyone have any recommendations how I can accurately check my emissions for cheap now that I don't need to get my car smogged? The sniff test I'm sure is very bad for me and also inaccurate. It was nice finding a smog place that wouldn't charge me until I passed, but I ran out of time.

Thanks in advance!

[mwebb]

first test results show
semi high HC but also
only 9% co2 with 8% 02 @ 2500 rpm

if the cat was working well expect over 14% co2 and 1% 02

your cat is dead er than dog poop OR the cat was not "lit" during the testing
at 220k miles if that is the original cat ....?

[mango]

Thank you, mwebb! I like the term "dead er than dog poop". I gotta remember that one haha

I kinda wrote off the cat being the problem because I passed with respectable numbers when I swapped back to the Cali o2 and ECU (last test). Am I wrong in thinking that way?

I'm pretty sure the cat was good and hot during all the tests. I'd take it out and romp on it for a while before each test. The smog test station guys would do the same to the car before each test. It was in their best interest because they only get paid when I pass.

As far as I know, yes, it's the original cat.

Thanks again

[mwebb]

first test results show
at 25 mph
semi high HC 112 ppm but also
only 9% co2 with 8% 02 @ 2500 rpm

if the cat was working well expect over 14% co2 and 1% 02
===============
the cat works by combining HC and CO with 02 to form
h20 and C02

your test results show that you have plenty of 02 and HC
but C02 is low at 9%
so the cat was not doing what it is supposed to do

or
it could be dilution , an exhaust leak after the cat but before the tail pipe ,
atmospheric air could be mixing with the exhaust gases
BUT
there was no dilution on your other tests so unless you have an intermittent exhaust leak that only shows up when you exchange the ECM and AFR / 02 sensor .

then
your cat is dead er than dog poop

[drago6817]

Originally Posted by mango

Ayudame with your knowledge, amigos!

I converted my 94 vx from CA to Fed in 7/08. To my surprise, the conversion went off without a hitch. I went from low to mid 40s to averaging 51mpg in my mostly city commute. (me=very happy). When I did the conversion, I made sure to shield the wiring. I also left the original 4 wire plug intact so I could switch back if need be.

In 10/09, it came time to get smogged again. I wasn't able to pass in Federal mode. It came down to crunch time, and I swapped the ECU and o2 sensor back to CA versions, and passed no problem. I love the mpgs of Fed mode, but don't want to be a gross polluter! Could you guys help me figure out what's going on?

Original test in Fed mode:

Tune up- cap, rotor, wires, plugs ZFR4F-11, air filter


Replaced Bosch L1H1 wideband o2 sensor with NTK L1H1 wideband o2 sensor. Ran tank very low then added a little 100 octane gas at Smog shop's recommendation.


Finally I ran out of time and put the old CA L01 ECU and 4 wire CA o2 back in and passed no problem

Subsequently, I checked my soldering/wiring, redid my ground with a nice gold ring term (not sure what it's called exactly), and tried an A00 ECU instead of A01. Just by giving it the sniff test, I can't say I've noticed any improvement in Fed mode emissions.

My only small suspicion is that there is about an inch of exposed wiring without shielding at both ends of where I did the new wiring. Could that be enough to mess me up? Lean burn mode is still working very well; I notice with pedal feedback and acceleration and also by my mpguino.

The car has 220K miles on it, but runs really really well. There is not suspicious behavior with the car that would make me suspect any problems had I not failed smog.

Also, does anyone have any recommendations how I can accurately check my emissions for cheap now that I don't need to get my car smogged? The sniff test I'm sure is very bad for me and also inaccurate. It was nice finding a smog place that wouldn't charge me until I passed, but I ran out of time.

Thanks in advance!

Your cat is fine, it just wasn't designed for lean burn. Modern 3 way converters need a balance of pollutants in order to work, certain pollutants are split in order to supply the products necessary to split other components, thus when you lean burn and produce TONS of NO the cat will not work as designed. This is why lean burn Hondas have special lean burn cats. Get the cats off the Fed civic and you'll be in business.

Sort of ironic how so many ecomodders have converted to fed to help save the planet but are actually polluting it all to hell because they didn't transplant the full system, but just the fuel economy bits.

read more here: en.wikipedia.org/wiki/Lean_burn

[mango]

Originally Posted by drago6817

Your cat is fine, it just wasn't designed for lean burn. Modern 3 way converters need a balance of pollutants in order to work, certain pollutants are split in order to supply the products necessary to split other components, thus when you lean burn and produce TONS of NO the cat will not work as designed. This is why lean burn Hondas have special lean burn cats. Get the cats off the Fed civic and you'll be in business.

Sort of ironic how so many ecomodders have converted to fed to help save the planet but are actually polluting it all to hell because they didn't transplant the full system, but just the fuel economy bits.

read more here: en.wikipedia.org/wiki/Lean_burn

I appreciate you chiming in here! It is ironic indeed and I hope to put an end to it.

I wasn't aware there are different CATs. I can only find 18160-P07-A00. Do you know of the part number for CA emissions?

This post from a guy that seems know what he's talking about (I love guys that seem to know what they're talking about) says that there is no physical difference between CA and Fed VX CATs GasSavers.org - Helping You Save at the Pump Hypermiling and Fuel Efficiency Forum - View Single Post - Civic VX Emissions Failure - VTEC Malfunction, or Hopelessly Epic Melodrama?.

Please help prove to the contrary 'cause I'd love to get this damn thing figured out and get back to the Fed equipment with those beautiful mpgs.

Thanks!

[roflwaffle]

Have you called up a Honda dealer and asked whether or not there's more than one model number for your M/Y cat?

[fx57]

I have a '94 VX federal which I imported into California a couple years ago.

The smog check passed, so it is possible for a federal vx to pass CA smog. Lean burn works great... getting 55-60mpg highway

I got:
15mph CO2=14.40 O2=0.00 HC=47 CO%=0.04 NO=485 PASS
25mph CO2=14.40 O2=0.00 HC=30 CO%=0.03 NO=451 PASS

I have to do a smog check this week to renew, so I'm crossing my fingers...