my 97 sl2 has ran great and I just hit the 160k miles. I use to get
27mpg in the city and 35 to 37mpg on the hiway but recently something has changed. My mpg is now about 24-25mpg on the hiway and 20 in the city. Pu new plugs in as normal (twice a year) but that didn't seem to mke a difference. Over the last 2 years the car has had new plugs, new cts, new air filter, changed oil every 3months, new tires and struts all around, upper motor mount and the sensor that is up front by the air intake. ( it is actually the same one as the cts ). and finally the forward o2 sensor. So where should I start looking to find out why the drop in mpg's. I did notice that when I changed wires that 3 terminals were very corroded on the same coil ( or whatever they are called) which a cleaned and buffed off then put conductive grease on them but noticed that they had corroded up again after about a year. The other set is nice and clean and always has been so. Is that a coil problem with that pair or just something that happens. I really guessing at this time so please point me in the right direction. Phil