Help With SMOG – TUNERCAT

[1997 Z71]

I'm new to Tuning software and could really use some help.

I can’t pass smog. I have a, never fired, new motor in my 94 Firebird. Stock V8 with a 6 speed tranny. Hooker smog headers and a K&N air cleaner are the only mods. I purchased a computer from this forum that is a stock 6 speed tune. The idle in open loop is good at 800-850 RPM. The RPM in closed loop is 1000-1050. The low fan kicks on at 227 DegF and the high fan kicks on at 236 DegF. I am new to TunerCats Pro and could use some help. The smog guy suggested that I go after the O2 sensors and the Cat first. I have a Datalog of the O2 sensors. If someone could look at it, I could use the help. How do I verify if the computer in my car is tuned for a manual or automatic transmission?

Failed smog. Smog report.
CO was 2.17% at idle and 2.16% at 2500 RPM. Allowable is 1.00%.
HC at idle(1050 RPM) was 164 ppm with an allowable amount of 100 ppm.
HC at 2500 RPM was 86 ppm with an allowable of 130 ppm.

[EagleMark]

I think when inspector said go after O2 sensors and Cat first he was suggesting to change them to new.

Do you have origanal PCM to read tune from? I have a 94 manual tune here you could compare to. Look at DTC codes for transmission and you'll see most are unchecked for manual and chacked for auto.

[1project2many]

High HC and CO in a stock configuration are generally from incomplete combustion. If the EGR and all mechanicals are working as expected look to your configuration change as a potential source for trouble. Some of the combustion reaction takes place in the exhaust manifolds during the exhaust stroke and changing to headers may have cooled exhaust gasses enough that the reaction is slowed or stopped. Also, the heat provided by the exhaust is used to warm the catalytic converter to aid in getting / keeping it working as well so again, the headers may be the cause of the problem. A very simple method to try and clean up emissions is to add a small amount of spark advance at idle and 2500 rpm where the tests are run. This will start the combustion reaction sooner, heat the pistons and heads slightly more, and hopefully the combination of these two will clean up what's coming out of the cylinders enough to pass.

[91ss]

Did it and does it still have an air pump?

My 91 caprice would struggle passing emissions even after everything was new. Discovered the diverter valve was frozen in the dump position. No extra air was available to the cat to properly help process the exhaust gas.