Hello the camp...new member to your forums needing some assistance.
We recently helped my daughter buy a 97 HX specifically for the fuel mileage aspects. She drives the car back and fourth to school which is about 18 miles one way most of which is highway. After driving it for several tanks at various speeds....first tank 75 ...then 70...then 65...then 60 (Which is hard to do when the speed limit is 75 on this TX Hwy...bless her heart she was a trooper to test for the sweet spot on mileage).
I have read you need to keep the RPM at or below 2500 rpm to reap the benefit of the HX's fuel economy which we have done repeatedly.
The problem is that at any of those speeds the best we have done is 33 mpg.
There is no CEL and the car runs and drives just fine. I have replaced the air filter (which was a mess) spark plugs, cap/rotor and just put new Michelin tires on it (not just for economy...it needed tires anyway) as well as an alignment and so far nothing has had an impact...still 30ish mpg.
I am going to try cleaning out the EGR valve next and check the timing as these have been suggestions.
Anybody have some insight as to why this HX is only getting 30-33 MPG with no check engine light? She is not using any fancy driving techniques but she is also not a lead foot so I really don't get it. This car I would think should be getting into the high 30's low 40's easily....
