Failed smog

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stewart in slc
Posts: 54
Joined: Tue Jan 06, 2009 5:54 pm

Failed smog

Post by stewart in slc »

I just had the annual smog check and my hydrocarbons are way high. I'm not in cali, the land of smog nazi's, but I need it to pass. Ideas?
It's a 1981 528i 3.5L w/ standard fuel injection.
crazyfastman
Posts: 92
Joined: Tue Jan 06, 2009 8:13 pm
Location: Cincinnati, OH

Post by crazyfastman »

I'm not an expert on this, but your mixture may be off a bit. Maybe it's running a bit rich.

If you are really having trouble, wait until your tank is low and replace the gasoline with alcohol. That's how I passed the sniffer when we still had them in Ohio. Ethanol or propanol (rubbing alcohol) will work and shouldn't mess up any other systems, but try general tune-up stuff first.
77 530i
82 Alfa GTV6
81 323i (Sparky)
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Mike W.
Posts: 2790
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Post by Mike W. »

What does the O2 sensor say, what are the readings off it? That is absolutely the first thing to check, do that and we can go from there. It controls mixture, so...
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
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