Hey Scotty! I just recently bought a used 1995 1.6L Toyota Corolla EX. Popping open the engine bay reveals everything is in very good shape. No collisions, accidents, or anything of that sort as it only had one owner. Brand new tires everything runs great. The dealer said the car has very good gas mileage however I've noticed that whenever I hit really bumpy roads or accelerate the car but throttle because of situations like high traffic activity the gas goes down kind of fast. I've also noticed that when there's a lot of movement from inside the car causing the vehicle to rock back and forth a little the gas will go down sometimes in chunks. I recently did an oil change 5W-30 full synthetic castrol gtx and checked the air intake filter and everything looked good no leaks coming from the bottom. All things considered I don't understand why the gas is going down relatively quick. The car only has 178k miles on it. Am I driving her wrong or is there something else like bad fuel econ from my exhaust or maybe the muffler is going bad, but I doubt it because nothing comes out and no suspicious sound coming from it? I'm just getting into cars and have been watching quite a few of your videos which I find to be very helpful. Any thoughts?
1995 1.6L Toyota Corolla EX (...) The dealer said the car has very good gas mileage
The dealer lied.
The EPA rated the automatic version to get 25 mpg combined (23 mpg city) [1]
The manual did just a bit better at 27 mpg combined (24 mpg city) [2]
( ~9L/100km combined, ~10L/100km city )
I wouldn't call it 'very good', nor 'good' to be honest - definably not for a car that small
(the 1995 Corolla is about the size of an old Yairs sedan, but performs worse than a modern RAV4)
that's about the same economy as a Ford Explorer 2.3L...
is there something else like bad fuel econ
There can be lots of things, these 4A-FE engines didn't have overly complex engine management.
Most of these didn't even have a MAP sensor, nor VVT, nor most economy management tech.
Additionally, being made before 1996, it may not have an OBDII port for diagnostics.
BUT, first to determine if there's an MPG problem, we need to know the MPG.
Assuming there's no MPG reading on the trip computer, if it has a trip computer...
MPG = (odometer when fulling - odometer last time filled) / (gallons filled)
Both times it has to be consecutive and filled to the max, but you don't have to get to empty or even close to it.
If it does get bad fuel millage (bellow 20): clean your intake, check that there's not significant cat back pressure, that the exhaust lambda is within reason and if everything checks out, that's just how it might be.
If it has an OBDII port (although in 1995 they didn't have to have one) you can check if the O2 sensors (if equipped, these usually were) are functioning correctly.
Additionally, inspect / replace the PCV valve.
Any thoughts?
Remember that you have a timing belt that may snap of old age.
According to a previous thread [3] this is a non interference engine, so it's probably not that much of an issue.
[1] https://www.fueleconomy.gov/feg/noframes/11923.shtml
[2] https://www.fueleconomy.gov/feg/noframes/11924.shtml
[3] The answer to the following thread is a list of interference and non-interference Toyota engines: https://carkiller.com/scottykilmer/qa/toyota-3mz-fe-engine-interference-or-non-interference/#post-195058
