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Old 12-15-2011, 08:33 AM
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roadfrog roadfrog is offline
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Location: Chilliwack, BC Canada
Join Date: Oct 2009
Posts: 1,096
Mein Auto: 2003 745i
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!
OMG. I do NOT know where to start here.

OK.... First of all, the exhaust valves have nothing to do with this and I did not say anything about exhaust valves. It's the SECONDARY AIR passages in the heads! They are very small and coke up, especially if you have failing valves which push more carbon into them.

Furthermore, do you realize how many people here at Bimmerfest have replaced their ENTIRE secondary systems, including the "rubber hoses" you keep referring to? Y pipes, diverters, pumps, hoses, etc, ALL to no avail - the SES errors return. I realize you have only 13 posts and have perhaps not read alot of the info given here by others, but google/search it and see for yourself.

Also, regardless of what the sec system does (we all know what it does by the way)....if you have a fault code - or two in most cases, YOU WILL NOT pass emissions testing.

Lastly, DO NOT accuse me of BS'ing! I am in Law Enforcement, not vehicle repair, nor am I a vendor/sponsor. I have NOTHING to gain with this info.

Last edited by roadfrog; 12-15-2011 at 08:36 AM.
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