OK so I would like a little input on this. A short time ago I picked up a 2004 with about 170k on the clock. After getting it I did a mini tune up; plugs, air filter, oil change and intake gasket. Shortly there after that the primary O2 sensor died and I replaced that. But I have been surprised that I am getting 30-31 mpg driving like a grandma. From what I have seen online this might be as good as can be expected but I can't understand why and just want to make sure I am not missing something. So here is a comparison, both cars driven the same route alternating days filling up at the same gas stations (though different grade) by the same driver.
2001 Audi A4 1.8, turbo charged and slightly modified for 207 horse/245lb-ft torque with ~235k on the clock. With this car I can get 29.5-31 mpg on my commute. While this car is a manual transmission which should help gas mileage it also has quattro and weighs almost 1000 lbs more. Also within the last few months I changed the O2 sensor on this car and the mpg went from ~27 to 29.5-31. So I saw a significant jump with the new sensor, but. I saw no increase with the Toyota's sensor change.
So I can't quite understand why the Toyota seems to barely do better than the Audi which makes me think something else is amiss. I have no codes and the vehicle does seem to drive fine; no stutters or stumbles. I would say it seems rough when pushed but I think this is common to most small 4 cylinder engines. The only other thing I have noticed recently is a ticking sound when sitting in drive. If I put it in neutral or park the sound goes away.
Any ideas on what I could check? I have monitored the O2 sensor circuit after replacement and it is oscillating like it should and the computer does say it is running closed loop.
2001 Audi A4 1.8, turbo charged and slightly modified for 207 horse/245lb-ft torque with ~235k on the clock. With this car I can get 29.5-31 mpg on my commute. While this car is a manual transmission which should help gas mileage it also has quattro and weighs almost 1000 lbs more. Also within the last few months I changed the O2 sensor on this car and the mpg went from ~27 to 29.5-31. So I saw a significant jump with the new sensor, but. I saw no increase with the Toyota's sensor change.
So I can't quite understand why the Toyota seems to barely do better than the Audi which makes me think something else is amiss. I have no codes and the vehicle does seem to drive fine; no stutters or stumbles. I would say it seems rough when pushed but I think this is common to most small 4 cylinder engines. The only other thing I have noticed recently is a ticking sound when sitting in drive. If I put it in neutral or park the sound goes away.
Any ideas on what I could check? I have monitored the O2 sensor circuit after replacement and it is oscillating like it should and the computer does say it is running closed loop.
