I am looking at getting a set of headers for my 95 T/A. I have found a set that has teh 02 bungs, and the EGR on them, but they do not have the AIR. Is this an issue, or would it be ok without them, and what exactuly does the AIR do? Any help would be great. I know I would need to get 02 extensions for them, and they come with the gaskets and all the bolts.

Thanks,
Travis

 

It depends if you are wanting to stay emissions legal or not. To stay legal, you need headers with the AIR. If you are in a place that doesn't test, delete all that stuff.

 

I searched some more and finally found that if I took the cats out, that I wouldn't need the AIR in the headers. Can I just uhook this from the manifolds in the car? I saw that I would have to get the PCM tuned if I unhooked them?

 

emissions isn't an issue here in WV. How could I delete the AIR, and what would happen if I got the EGR block off plates?

 

Travis, 1995 is OBD1 PCM.. The air pump only runs when engine is cold, it injects air into the manifold to help burn off the rich cold mixture. This unburnt exhaust will shorten the life of the CAT. So if you delete the cat deleting the air will not harm anything except the atmosphere. To delete the air just pull the connector off the pump and tuck it behind the ABS unit. Do not cut the plug off, pull the relay or pull the fuse doing any of that will throw a SES lite. You can then physically remove pump hoses etc. On OBD1 there is no CAT diagnostic errors checking, you can pull the CAT without any codes showing up. If you delete the EGR stuff without programming EGR off (tuning), it will throw an EGR failure code

 

so I could delete the cat, and the AIR, and it would throw the SES light. After that, if I pulled the pump and the hoses, and the fuses, would the light then go off? I didn't want to get into programming the computer right now, so I think I will leave the EGR stuff alone. Is there a diagram on here to show where the air pump and hoses are located?

 

I think if you unplug the AIR pump, the PCM will know and it will throw a code. Worst case just leave it plugged in and plumbed to nothing to pass your emissions test.

Without a cat, you may need to adjust the timing idle through the computer though... I had to retard idle timing to 5 degrees from 20 to pass hydrocarbons and CO.

 

No that's incorrect it will NOT throw a SES lite. The OBD1 air pump SES error is pretty basic.. when the PCM picks the air pump relay the PCM looks for +12 volts on the sense lead in in the harness connector. Therefore just unplug the connector leave the harness intact and the PCM will think all is OK. There are no CAT errors on a OBD1, you can do whatever you want without any SES lite.
EGR is different, on OBD1 when the PCM picks the EGR solenoid it looks for a slight drop in RPM, if no drop it throws a code. You can tune this out by raising the EGR enable RPM to 7000 RPM therefore it never picks and won't ever test for a failure. This is OBD1 only OBD2 is a completely different story for all three...much more complex. Not sure where you got headers with EGR and no air never seen half emission headers, if they really don't have air you will readilly see where the hoses and pump are when you follow the dangling check valves and associated hoses going back to the pump.

 

No. In the OBD-I system, there is no check for actual AIR flow, like there is in OBD-II. And the electrical check only covers the power supply to the pump, not the actual connection of the AIR pump. 93-95, as long as there is a good fuse and relay in the feed to the AIR pump, you can delete all the AIR components without setting a code or turning on the SES light. OBD-II will catch you though, because it checks for the pump connection, and cycles the pump on and off, looking for a change in the O2 sensor voltages to verify air flow. But not in OBD-I.

The OBD-I diagnostic for EGR flow (change in MAP when cycling the EGR valve) is also not very sensitive, compared to the OBD-II diagnostic. I'd say that 80-85% of the OBD-I cars have not set a code when deleting the EGR valve. If you attempt to delete the EGR vacuum solenoid, you will get a code, but you can eliminate that code by inserting a resistor in the EGR vacuum solenoid harness connector.

There is no real performance gain from deleting these systems.... other than some minor weight savings.