cfl3794

I read it and didnt find a thing about the secondary Air injection system

Just call me Sean

iTrader: (1)

Exactly. It's a secondary system, the smog system. It would be like cutting off the cat, the only side effect will be that emissions may go up. The EGR is part of engine function though so it needs to remain.

ymeski56

Well that & premature Cat failure. & probably codes that you'll have to get used to seeing. I guess you don't get smog inspected & if you ever sell it, that will just be thier problem (although the sale wouldn't be legal in at least Ca.) Caveat emptor (Let the buyer beware)! I really doubt any gain, if in fact their is one, is worth the effort. Just don't forget to mention the alteration in future posts so "JCMS" is aware of it. It'll save you guys some time.

Just call me Sean

iTrader: (1)

No codes will be stored as long as the control solenoids remain hooked up. I did mention "if you don't have inspections". Without that tube there is no easy way to fix it other than deleting it. You can't be hooking plastic or rubber directly to the exhaust manifold, that sure won't last. The gains are mostly an easy repair and a cleaner engine bay, plus a very slight horsepower gain if you remove the pump too.

These type of "modifications" are pretty common, but you wouldn't know that ymeski because you live in California. Too bad for you. I get no inspections of any kind. You should see the vehicles on our roads.

ymeski56

I thought he was talking about the plastic tubes going to the TAB/TAD's.

flareside93

on our model fords, the o2 sensor is on an h-pipe before the main cat. so you can cut it off if you wanted. doesnt make a difference. so if his emissions go up and fails his cat then nothing would happen. his exhaust might sound crappy but thats about it if a cat fails.

ymeski56

You've never had one melt internally, seal off and explode. Doesn't happen a lot, usually just stalls the engine. Mine blew doing 70 mph. Lifted the rear tires off the pavement. Basically, the valves back-pressure and don't close properly. Undetonated fuel escapes into the exhaust, reaches the really hot Cat & Boom!