i had this problem a while ago where a code 27 would pop up i replaced the egr valve solenoid and it went away well it came back i replaced it again and the air pump went cause i keep blowing fuses,..... i replaced the air pump once already and i dont know what to do now replace the air pump or the egr valve solenoid????? the car is losing gas mileage and backfires frequently. all the ignition has been replaced by msd, but i do have a exhaust leak,... if anyone can help that would be awesome thanks!

 

Delete the air pump and EGR system... Problem will be solved.. Well unless you have emmisons testing in your area... Upstate we dont have it..