I have a problem that I would like some feedback on. Let's start with my situation. I am a serviceman living in Europe with a first generation sti from Japan. I have a late edition 93 model sti.

Ever since I came to italy, I have been getting terrible gas milage. about 12 miles per gallon. Sometimes the car sputters and sounds like the engine is flooding, like it is getting too much gas. I notice that I am getting normal boost ( about .8 bars). When I get to about 4k rev and give it some gas it does not go any where, I do see the boost kick in and the waste gate actuating. Let me reasure that it is not the clutch, because I just put in a new clutch couple of months ago. This has been going on since i move here. Almost a year ago. I thought it might be the ecu, then the O2 sensor( in this case, wouldn't the engine lite come on) then I thought it might be the mass air sensor. I have a hks intake and exhaust, I thought I should mention that to help out. This never effected the way the car ran before. I hate to take the car to the dealer but, if worse comes to worse I will. I enjoy working on the car, I take pride that I can do most things, but this has me stumped. There are so many posibilities on what could have gone wrong. Thanks guys!

 

thanks for your replies,

1. the Italian gas is not leaded. everyone swears that it is 96 octane.

2. there are no damages to the exhaust and the piping.

3. I just changed the plugs from ngk type r's to ngk iridium 8's. That seemed to help on the power, little more smoother in throttle response but the gas is the same.

4. the o2 sensor is fine and the mass air sensor is fine also.

5. I will have to check out the cat. I just had it on the lift and didn't see any visible damage.

I almost forgot to mention that when I changed the plugs, I also notice the turbine spooled up much better. And that it read .9 bars, up .1 from before. the plugs also runs hotter so you will need a cooler running thermostat and change the coolant formula.