Engine Performance problem
1996 Ford Aerostar 6 cyl Two Wheel Drive Automatic 166000 miles
van has consistantly run at 21mgp since purchase.
last two month has dropped to 17mgp.
runs as smooth as before.
would a code reader be able to give me some direction as to what changed?
would ECU be able to change settings?
Is the check engine light on? There are plenty of small maintenance items that can have an effect on MPG, including but not limited to air filter, fuel filter, weak spark plugs, low / incorrect tire pressure and much more.