Hello Folks,

I am getting 16 mpg down from 27 - 29that I used to have onmy '98 T5 with manual transmission. The car has133.000 miles. I had bad thermostat/coolant temp. sensor problem, which caused engine running cold. I thoughtthat was the cause, but the mileage is still the same after I replaced thermostat/sensor and the coolant temperature is normal.The carhas new spark plugs, wireshave 02/2004 printedon them, and so I think that's when previous owner replaced the wires. The rotor looks fine, without cracks. There are no warning lights on the dash, but the engine runs rough to my ear. I had cyl01 misfire and multiple misfiremalfunction codes in past, so the rough idling. But after I did the thermostat/sensor job, the check engine light is gone...hopefully forever(I also fixed vacuumleak in one of the tubes that come out of air intake). I hate to start replacing things without knowing where to look first. The engine delivers tons of power and is fine except the rough idling. Can it be injectors? Can it be fuel leak? Thank you

 

Clean your throttle body, MAF, and change your plugs. There are specific cleaners for the throttle body and MAF and can be purchased at a NAPA shop.

r.