Vacuum Leak Diagnosis Cost
When locating a vacuum leak, we recommend using a smoke machine to find all of the areas that are leaking.
After all of the known vacuum leaks are repaired, we recommend performing a drive cycle test drive to verify that the air-to-fuel ratio has returned to normal.
When an engine has a vacuum leak, it may:
1. Idle rough
2. Be hard to start and/or keep running when cold
4. Hesitate under acceleration
5. Get poor fuel economy
The Check Engine Light may illuminate setting a P0171 or P0174 code, indicating that the fuel system is running too lean due to the vacuum leak.
Vacuum leak symptoms can be caused by a defective mass air flow sensor, ignition misfires, a defective idle air control motor, or a stuck-open EGR valve.