I picked up a 90 HF not long ago. I installed new plugs, airfilter, oil, tranny fluid, fuel filter (the spark plug wires look good). Im only getting 30-33 miles a gallon whats up with that?

why would I get such bad mileage? timing is off maby?

Also my mechanic had to cheat it to get it to pass emissions, I think its running way rich.

code 10 is going off under the carpet which has to do with intake air temp.

 

maybe your iat is bad. that could be a big part of your gas mileage problem. and your mechanic should have checked timing, and should have probably told you to get a new iat or at least check to see if its functioning.

 

what is an iat

 

Air intake Temp Sensor. It is on the runner #1 closest to the timing belt. It's on the side of the intake manifold. It's a white sensor with a 2 prong plug.

 

how would I check if its bad?