I have a '94 T'bird that runs rough. It is the LX model with the 4.6l
V8 and has about 180k miles on it.
One day i filled up the tank and my car started running really bad.
Leaving a cloud of smoke behind and getting about 3/4 mpg. I added
some Heet to it and it did not help.
I took it to a garage and they recommended replacing the EGR valve,
EGR position sensor, 4 oxygen sensors, spark plugs/wires, cleaning the
injectors and the fuel filter. After they did that, it still ran bad.
They replaced the mass airflow sensor and that did not help. Next they
replaced the computer and it got better.
It runs now, but still misses a little. It seems to be getting much
better mileage- maybe 18-20 mpg, which is about as good as it has
gotten for a while. The roughness if very noticeable at low rpms (less
than 1k) or if I hit it hard, and is less noticeable at higher rpms.
The garage says that all cylinders check good on compression and that
all injectors are matched and that the timing is right on the
The garage recommended driving it for a week and seeing if the
computer 'learned the car and all the new sensors'.
I have been driving it for about three days and it is not getting any