Scenario: I need to get my hunk of junk LT1 through OBD2 emissions testing. After talking to Speed inc and Madwolf, I have narrowed down the available options. From what I understand, I will need to put the AIR pump back on my car in order to pass.

Here's my exhaust setup:
--Hooker LT's (front O2's plugged in here)
--No cats
--Mufflex Y
--Rear O2 simms

I know the PCM checks on the AIR pump by seeing if the O2 sensors detect the mixture leaning out when the pump turns on. Does the PCM just check the FRONT O2's, or does it also check the rear ones?

Edit -- According to my Helm's manual (page 6E-938, for those of you reading at home) the troubleshooting instructions for AIR pump operation say to check that the voltage of both the front AND the rear O2's stays under 350 mV... so I guess that means that both pre-cat and post-cat readings matter. But the question still stands...


Would running O2 simms make the PCM think the air pump isn't working?

Thanks guys.

 

No, all the simm's do is send a constant signal back to the PCM telling it that "things are ok back here", when in reality you've got off-road pipes installed. If your emissions entails them sticking a sniffer up the pipe, you might want to put the cat. convertors back in the car.

.....also, the only way you'll fail emissions without the A.I.R. pump installed is if they do a visual inspection and look for it.

 

Encouraging, but I don't know if I buy that... although you can program out the trouble code for the AIR pump, you can't get rid of the OBD2 readiness monitor for it, which is set by the test I described in the first post.

Any more info?

 

Oh yeah, you got OBD2.....mah bad. That's not an issue with mine...