Last month I had to take my 87 GL-10 wagon EA-82T thought emissions. Here’s the problem… I have no Cats. 2.5 inch turbo back straight pipe, and I have removed most of the emissions controls off, mostly because they were in my way and looked better without them.
I took it thorough at first without doing anything. Just to see what kind of numbers it would blow.
Before:
Cruise: HC = 100, CO (%) = .46, CO+CO2 = 15.86 All passes.
Idle: HC = 274, CO (%) = 4.37, CO+CO2 = 16.47 not so good.
So I got to thinking… (That can be scary) I back probed my O2 sensor and found out that it was working fine at cruse, but as soon as it got back to idle it went flat. This causing the rich idle. Installing cats was out of the question, so I installed a three wire heated O2 sensor.
After:
Cruise: HC = 56, CO (%) = .13, CO+CO2 = 15.63 All passes.
Idle: HC = 152, CO (%) = .05, CO+CO2 = 15.25 Also all pass
Not bad $50 O2 sensor over a $250 cat, that I don’t want anyway… I would say it was a worthwhile investment.
-=Suberdave=-
david@suberdave.com
www.suberdave.com