Keywords: I have a 2001 Toyota Highlander and about a year ago the check engine light came on, we did not remember the code # the first time it was checked and the second time it read P1120 so our mechanic said we needed to wait for the check engine light to come back on. It has not come back on and the only problem we have been having is that we fill up the gas tank more frequently now and do not get good millage. The car runs perfectly other then not good gas millage. Poor gas milage, what can be the cause? Any answers?

You could get the codes read again to see if something has come up. Air up the tires is a big step towards good gas mileage. Take it 10% over the recommended PSI for another 5% MPG. If the engine has close to 100,000 miles, it could use a set of plugs and a new O2 sensor.

It should be able to be read w/o the engine lite on.Try taking it to an autozone and they will read it for free.Have you tried putting in a couple of cans of WHOLE engine cleaner?If an injector is dirty it should clean it.Hope this helps.

C0004 codigo Toyota Highlander 2002