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1991 Honda Civic Si b16a swap fouled plugs bad gas mileage


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Have a 91 civic Si with a b16a swap in it. Car was not starting a few days ago, turned out to be fouled spark plugs (all of them). Replaced them and the car fired up and ran great for about 5 days. Now the car will not start again, plugs appear to have already been fouled out. I also am only getting 13-20 mpg. ENGINE IS RUNNING EXTREMELY RICH. Here is my question


I know that this car has a bad o2 sensor (check engine light code points to it). Could a bad o2 sensor really be the cause of this poor gas mileage and how quickly my spark plugs are fouling? The plugs were coated with carbon, not oil. Engine does not leak or burn any at all.


Could a bad fuel regulator be causing this? My fuel regulator also appears to have a adjuster dial connected to it. How do I test the fuel regulator or adjust it?


What else could it be? Dizzy? Dizzy cap? PCV Valve? Fuel injectors? Fuel regulator? Fuel filter? Any help would be great appreciated, I am stumped.


NOTE: Problems appeared to begin happening after I adjusted my FITV and cleaned my IACV. Could this be related at all? Came to this forum as a lot of you out there are much more experienced than me! Please help!

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I have a 1995 del sol si with a b16, the engine was rebuilt about 7k miles ago.


I also have a burning problem. My spark plugs are ok but less then a week after I replaced the dis. cap and rotor the points on the cap were already fouled out and had an excessive amount of build up on them. My check engine light comes on sometimes. It is turbo'd, maybe they didnt tune it right but it has a great fuel/air ratio.


qzany, did you figure out what it was?


I also cleaned out the fitv and iacv because it was idling ridiculously high and by cleaning the fitv it brought it back to normal.


Whats the frp?

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