why is my 1995 astro van running rich in fuel
The number one cause of this is dirty/contaminated/malfunctioning oxygen sensors. They get dirty and misread, but there is no code because the unit is working electrically. For most people, I suggest a new one every 60 to 80,000 miles just because they do get dirty, and a bad reading is almost guaranteed to clog your catalytic converter in short order. Also with the price of gas these days, a new O2 sensor can pay for itself in short order. Also, make sure your throttle body is clean.
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