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Discussion Starter · #1 ·
It is automatic and has 1.6L engine. It currently has 180000 KM on the odometer. I only get about 20-21 MPG in city driving. So far I have changed air filter, spark plugs, ignition wire set and MAP sensor. I cleaned the PCV valve. But there is not much improvement. I couldn't find MAF sensor on this car.
The car drives fine with no issues. But the poor fuel economy is driving me nuts because I drive this car a lot in town.:(

Any ideas?

3,151 Posts
ok here are my suggestions:

1. STOP replacing parts at random! i have yet to figure out why people want to do this! air filter and plugs, sure they're cheap but can also be visually inspected. copper plugs can even be cleaned with a wire brush and regapped provided that the electrode is in good shape. wires and a MAP sensor aren't so cheap. the wires you could have tested resistance with a multimeter to DIAGNOSE them as being the problem. map sensor, similar story and it can be cleaned if you really feel like doing something with it.

2. now let's try to DIAGNOSE the problem and not throw more random parts at it than you already have. first i want to say that yes that is on the low side, but for all city driving isn't terrible. city driving will kill fuel economy on any car.

now let's take a look at what you can do to get to the bottom of this:

- check engine light. single most important thing here. is it on? get yourself a code reader if it is. you're in toronto, visit princess auto if you want a super cheap one. CT when they're on sale is also a good deal. mine came from there and was maybe $150 after taxes. it was not a cheap one, i have seen them as low as $30. best investment i ever made.

- try changing gas stations if you go to the same one all the time. not all gas is equal. sometimes they get crappy shipments. not bad gas, just lower energy content is all.

- check your trans fluid. if its never been replaced, that can cause more friction in the system reducing FE. use the look/sniff/feel test. put some on your fingers from the dipstick. at that mileage it will be brown and this is normal, but shouldn't be approaching black or dark brown. smell it. should not smell burnt. rub it between two fingers. should be smooth, not gritty. if it fails any one of those, flush. a full flush please, not drain pan and refill which is a waste of time and money.

- check for a brake caliper dragging. the front brakes on these cars love to seize. strangely, you can't really feel it pull. at least with my car it never does when i have had seized caliper.

- want to clean the engine? my opinion is forget injector cleaner. full tank of premium and drive it hard. accelerate hard, take it out on the highway. premium has more cleaners in it, most premium has no ethanol. combine that with extra heat and forces and it'll clean it up a bit.

- inspect throttle body, see if its blocked. easily cleaned with carb or TB cleaner.

- try a compression test. possible a valve or ring isn't sealing as well as it should. a tester isn't expensive. again, princess auto or CT.

- look for fuel leaks. even a small one.

- don't trust your gas gauge for an accurate tank reading. reset your trip meter when you fill and then next refill use the volume put in to fill the tank and the kms traveled to determine your FE.

- check your driving habits. driving hard will drop your FE easily. so will a bunch of heavy crap in the trunk.

- tire pressure. min. is 32 psi. i like 36-38 myself.

- get oil changes on schedule. single most important maintenance item.

- look for vacuum leaks. see if there is anything obvious, then get some of the spray start fluid. spray it around intake manifold where it mates to the engine (under too, that intake gasket is crap if original), all the vacuum lines, etc. the idle will pick up a bit when you spray the leak. look for breaks in the intake tubing as well.

- does your car heat up properly? although would be unusual, a thermostat stuck open would prevent your engine from heating up fully (accidentally bypassed my t.stat years ago when i installed an external engine heater...long story but it won't heat up) and that means that the computer is unable to go into closed loop mode. the short of that is that it cannot use its sensors properly and there is no fuel trim. open loop mode all it does is dump more fuel into the engine as that is the safe mode.

that should be enough to keep you out of trouble for a little while.
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