neversummer

I need emmisions again. I am trying to get ANY parts, so 94-97 are included. My question is this:

Is the driver side exhaust manifold used for air going down the exhaust, and the passenger side used for air going to the EGR / back of intake manifold? OR:

Is the passenger side for air going down the exhaust also?

After looking at 94-97, it appears air goes down both manifolds and there is a separate pipe for air to the EGR / back of intake manifold. I vaguely remember what my 93 pipes looked like, but wanted a more expert opinion.

And of course, does anyone have some spare AIR lines and check valves laying around they want to part with?

I don't need the EGR to work, because there is no testing for NOx here. (I understand that is what the EGR does the most.) But I do need it to look like the EGR is hooked up.

Right now I pass high idle, but fail the low idle. I think that pushing oxygen down the exhaust will greatly reduce my HC's. Would pushing air down one pipe and not the other mess up the O2 sensor's? Not pass emmisions as well?

Thank you all for any help - advice and parts!

Injuneer

The 93 is different than all the other years. It has an AIR connection on the driver's exhaust manifold. The AIR line to the passenger side goes behind the engine, through a check valve, and combines with the EGR riser tube from the passenger side manifold connection on #8.

neversummer

I remember that. But does the pass. side of a 93 have a one way flow of exhaust or two way? In other words, is the air just going down, or does air go up towards intake manifold? Or does it do both?

Either way I'll take whatever parts I can get. I'll make a 94-97 work and see if I can pass the visual emissions and hope that I pass the sniffer test.

95Blackhawk

pull a few injector plugs during the test. Only air will pass through the cylinder then.

Injuneer

The AIR pump only operates at startup, when the EGR does not operate. When AIR is flowing, it flows to the exhaust manifold. When the EGR is working the exhaust gas flows up the EGR tube to the intake manifold. The check valve for the AIR preventsw EGR from flowing back to the AIR pump.

neversummer

Thanks! I'll be working on this soon - just need parts!