I used to have a 1999 Malibu with the same 2.4 engine. You have the gas mileage right on target. My gas mileage was the same as yours since day 1.
I bought the car brand new and it was a piece of junk. GM shipped the car to the dealer with chipped window glass, and you noticed the chipped glass when rolling the window down. They also shipped the car without any paint on the bottom of the doors. The dealer had to remove all the doors and paint the unpainted metal in their body shop.
The car was shipped from the Oklahoma City assembly plant. GM has since closed this awful assembly line that shipped poor quality cars.
I traded the Malibu for a 2003 Impala which I get 32 MPG on the freeway with the 3.8 V6 engine. The Impala is also a much larger car.
Hello there, I'm the original writer of this review.
The 800 dollars included spark plugs, the coils (all 4 of them), the coil housing, air filter, fuel filter, crankshaft sensor, camshaft sensor, oxygen sensors, timing chain and guides and gears.
After all this, the car still ended up being junked because the chain slipped which caused the valves to hit the pistons. Poorly made junk from GM. Our Ford vehicles never gave us any problems except for the maintenance and the normal wear and tear items like rotors, brakes, etc.
No more GM for us. We have a Nissan, two Fords, and a Geo Prizm and we are proud that those vehicles are reliable.
A timing chain replacement, and all the sensors you mentioned are more along the lines of needed repairs, not a tune up.
The chain slipped probably because it was fixed improperly. Sounds like this car had a rough life overall, and was never really taken care of.
So you had that much trouble and disappointment due to GM's manufacturing incompetence, AND the mileage was that bad on a 4 cylinder... and you STILL went back to buy another GM product? No wonder they have gone for decades building junk cars... As long as people continue to buy, they'll continue to build their same sub par vehicles. I would never go back to a company that I received a brand new car from in the condition your Malibu was in. In fact, I would have returned the Malibu immediately, and went to the Honda dealer for a real car!
"The chain slipped which caused the valves to hit the pistons. Poorly made junk from GM"
I hate to tell you but the same thing will happen on certain Ford and Nissan engines if the chain slips.