I have a 1989 Toyota Camry 4cyl 2.0. This car has always got 28-35MPG easily. But since August it has become a third car for garbage and some occasional driving. I have put 700 miles on it since then. I filled it up two weeks ago and today I went to fill it again. My guage was reading a little less than 1/2 a tank and I thought it was just not working right. But no, I was wrong. I put in 9 gallons of gas for 186 miles which comes to 20.4MPG. What could my problem be? The engine runs great and has 700mile old oil in it. 10W-30. Maybe need a different weight of oil? If so, what weight?


Thanks!

If you just make quick little trips, then 20 mpg is not unreasonable. Go drive it someplace on the highway.

the thing is, I have taken it on 3 trips that were 15 miles each way and up and down one of our main state routes plenty of times. Going about 60MPH the whole way on both routes. Only about 10 miles of town driving.

any ideas?

Have you done a tune up recently? Put any air in the tires? Not enough information to give an opinion.

Not tune-up recently. It had one around 170k miles and it runs fine. I did however get new spark plugs a month ago. I always have the tires at 35PSI and I checked them yesterday and they were fine. The engine in this car runs very well and will for a long time. I also ran some deep creep (seafoam) through it recently.

it now has 204k miles on it

Did you give it a compression test? If you know the compression is good, then you can assume it's either a fuel problem or an ignition problem.

You know..., probably you have dirty injectors... if the car sat for a while...

What kind of cleaner should I run through and how much? How many times?

Thanks for your help!

Also, could I add some octane booster to whatever is reccomended for a cleaner?