[MSCW list] Hi Mileage RX-7 gas mileage

David Lane dlane
Sat Jun 14 14:55:45 CEST 2008

The brochures for the 84-85 RX-7s list EPA estimates as 18 city and 
29 highway, with an expected 22 mpg average.  The Car and Driver test 
of the car confirmed the 22 mpg average, so 12 mpg is very low.  I'm 
not aware of anything normal that would change the expected mileage 
as a function of age, so something is not right.  The suggestions so 
far have been good.

I might suggest that after you find the culprit, you run the car hard 
to blow the carbon out.  Carbon build-up can inhibit the springs 
behind the seals and create starting problems.  There are a couple of 
techniques to clean the engine--one involving some little water mist 
to steam clean it while running--the other involving an overnight 
soak with a fluid (is it ATF?) that will desolve the stuff and 
dramatically blow it out in a smoke cloud the next time you start the 
engine.  Please explore these things so you will have the details 
down before attempting them, though.  I don't have personal 
experience with them.

Best wishes,
David Lane
dlane at peabody.jhu.edu
'85 GSL-SE (Cartech Turbo)
Info on the car at:

More information about the MSCW mailing list