Need to keep gas on to keep engine running

Tiny
RJ198012
  • MEMBER
  • 1991 LINCOLN TOWN CAR
Car runs but sometimes makes a humming noise and shut off the car except when I press gas pedal it will stay on. When I'm not pressing gas pedal it will make a loud humming sound then car will shut off unless I press the gas pedal?
Thursday, November 17th, 2011 AT 3:38 PM

1 Reply

Tiny
DRCRANKNWRENCH
  • MECHANIC
  • 3,380 POSTS
This sounds like the Idle Air Control Valve has failed. It controls idle and keeps the car from stalling when load is put on the engine. This is from, accessories being on, decelration or quick changes in decreasing speed, changes in the pedal position and when coming to a stop. It does so by opening ports and this changes the mixture in an attempt to keep the idle steady.
This is related to another issue that could be the problem. A vacuum leak could be causing the howling noise as the leak is sucking air into a crack in a vacuum hose. The IACV is fed by a vacuum hose and is often a lrge one. It will demand more vacuum wioth the changes that I mentioned earlier. This in turn will make the noise and casue the stall or idle problem.
So, first look for a vacuum leak and then check the IACV.
Was this
answer
helpful?
Yes
No
Thursday, November 17th, 2011 AT 4:28 PM

Please login or register to post a reply.

Sponsored links