señordos

Hello everyone,

I took my vehicle in for the always-fun smog test. As you can tell from the
title my 1992 MR2 failed the smog test. I have a naturally aspirated 5S-FE engine. This is the first time that my car failed the smog test. Here are the results in the hope that someone can shed more light on the situation or at least point me in the right direction of how to repair the problem
Test 1 @ 15 mph
RPM @ 1879
%CO2 = 15.6
%O2= 0.0

HC (PPM)
MAX=121
AVE=31
MEASURED=119

CO%
MAX=0.76
AVE=0.10
MEASURED=0.36

NO(PPM)
MAX=807
AVE=237
MEASURED=189

TEST 2 @ 25 MPH
RPM@2095
%CO2= 14.4
%O2= 0.0

HC (PPM)
MAX=96
AVE=20
MEASURED=157

CO%
MAX= 0.65
AVE= 0.09
MEASURED=1.80

NO (PPM)
MAX= 747
AVE=199
MEASURED=58

As you can tell, my MR2 failed the HC test @ 25mph and the CO (%) test also at 25mph. Any tips or suggestions would greatly be appreciated.

Thanks

ac427cpe

how old are the plugs + o2 sensor?

señordos

ac427cpe,

As far as I know the plugs and the O2 sensor are the originals that came with the car. I have most of my vehicle's maintenance records and it seems that the O2 sensors have never been changed. Is that something you would recommend?

Thanks.

ac427cpe

yeah, I've had them go bad on 3 mr2's :\ (hopefully they aren't the origonal spark plugs!)

Headnsouth

Folks have passed smog tests after using auto-rx.
www.auto-rx.com

__________________
92 BMW 325I 171k
97 Saturn SWII 173k
98 Pontiac Transport 171k
03 GMC Sierra 35k

2002corolla

I say that the o2 may be a bit old and getting "slower" not keeping up with the ever changing exhaust charge or it may be coated preventing a accurate reading. It looks like both the 15 and 25MPh tests are not looking very happy...I'd change both the plugs and O2 to start ( they are both relatively cheap). GL