Q: Stalling issue and hissing sounds.

asked by on December 30, 2016

Motor acts like it wanna stall plus i hear a vacu leak that i cant find after i replaced all the plastic type vacuum lines that sits on top of motor "help"

My car has 200000 miles.
My car has an automatic transmission.

Hi There, It sounds like you definitely have a vacuum leak. High idle speed, stalling and hissing sounds are common signs of a vacuum leak. When a vacuum leak is present in an engine, this causes an excessive imbalance in the air/fuel ratio which creates a loss of power and causes the motor to run at a much higher RPM as a result of the increased oxygen present in the fuel charge being injected into the motor. I would recommend having an expert from YourMechanic come to your location to diagnose your vacuum leak as these can be very difficult and time consuming to trace.

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