Significant drop in mileage - help!
I am noticing a 25% drop in mileage recently. And I have no clue what caused it. Some details:
2003 MDX, 125K+ miles as of this morning.
All service done on time
Steering column replaced due to oil leak
Front axle replaced
Transmission oil changed
1 year ago:
New tires installed - bridgestone dueler h/l alenza - noticed a drop in mileage right after new tires installed (attributed it to the new tires till they wear in)
I usually get 19/20 in city and 23-26 on highway. However, since the move to central Illinois, the mileage has never been as good as it was but still hovered at between 18.5-20.5 mpg.
Since the last couple of months, it is now hovering at 15-18 and sometimes on highway gets to 20 mpg. Especially since the past month, it is hovering around 15.5-16 mpg.
My driving is not bad, I am very gentle with the acceleration and rarely ever engage in mileage lowering actions.
One of the things I suspect is the spark plugs. They were replaced as per the service plan (~100K) and I noticed the car was not as responsive as before and also noticed a slight reduction in mpg. The shop is very reliable and have done all service and other work on the car since 2.5 years.
I am not sure what I am missing and why the mpg would drop so suddenly.