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Old 12-15-2011, 07:49 AM
N62b44 N62b44 is offline
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Location: Usa
Join Date: Dec 2011
Posts: 85
Mein Auto: M3e46
Originally Posted by roadfrog View Post
More than likely you have the same problem many 7 owners have - carboned-up heads, which prevent air from the air pump to circulate through them. It has NO EFFECT on how the vehicle performs, but it will fail emission testing. FWIW - repairing this will empty your wallet of approximately 7-12k dollars. Are you also getting P0492 codes? Usually you get both.

If you have a similar testing system as we do here in BC, you are allowed 1 readiness code not set and still pass testing. Sooooo.....if you reset your SES light and wait until the one last readiness monitor is not set (which will be the secondary air system), and then proceed with testing, you will pass.

If you have anymore questions, fire away. I have become somewhat of an expert on this problem, through extensive and painstaking research.
Roadfrog, please don't bs here, it's all ok with your heads, just go and replace old rubber hoses coming from sec air pump to checkvalves, worst case replace check valves too!!!
Damn how ppl can say that bs about heads???? Either they want you To spend money in the shop??? Or they fg stupid???
Ok here is the deal:
Let's imagine you have build up on your exhaust valves, if so the engine would run very very rough, bc there would be backpressure and probably your engine won't last 100 miles with clogged exhaust.
But even if so, it does not do anything to sec air system! It only blows air on cold start to reduce emissions bc o2 sensors are cold and therefore cannot regulate mixture, that's why you need more air to help cats to clean co2!
It only blows air in exhaust manifold down to cats, that's it! In other words if your cats are Alive and engine is dead, but sec air system is ok, it will pass sec air test!
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