Secondary air delete bulletin

Does anyone know much about this: http://www.impalassforum.com/tech/engine/air_pump/air_pump.htm

Thanks,

Russ

What do you want to know? The bulletin outlines the approved procedure pretty well.

Some guys have gone beyond the disable procedure, and have had problems with subsequent emissions testing programs, unless you have the referenced sticker, which are no longer available from GM. Someone over there actually made some reproduction stickers. I think they may have even tweaked the sticker to say "delete" instead of "disable".

I do know that the TIS calibration file referenced in the TSB is not available for my 95. I suspect that the procedure only applies to US models and was never approved in Canada. But a tuner program and a cable can take care of that (at least, for 95 models).

I have never come across any explanation as to why the 94 was not also included. I would have thought it was basically identical to the 95.

By "secondary air" are they referring to the air pump?

Thanks,

Russ

Done this to my 96rmw. Had check engine lights on all time, mostly because of air system. Removed all the components, bought the sticker on eBay, and the dealer did the new tune. No lights since (knock on wood)

Clarification- the AIR system does not recirculate exhaust gas. (That's EGR)

When the engine is cold, it injects fresh air into the exhaust system to provide surplus oxygen, which is used to burn up the cold/rich mixture and heat up the cats to operating temperature faster. It reduces emissions by burning off the excess hydrocarbons during this rich running condition, essentially.

Once the engine (and cats) have warmed up the system shuts off.

Since the AIR system doesn't run when warm, and you're unlikely to do a smog test with a cold engine, there should be no impact to measured emissions whether the AIR is even present or not. Only a visual inspection may cause you problems (assuming anyone remembers what it's even supposed to look like!) or if the computer throws a code if it detects the pump wasn't running (maybe in 96 with OBD II, this happens? Not sure.)

I found a dealership that will flash the PCM for $50. He did my sedan today and he will do the wagon next week.

If it was going to be expensive I was considering trying one of those places like pcmforless that retunes the whole PCM but I'm delighted to get it done for $50 and stay stock.