Ford Mustang Forum banner

1 - 5 of 5 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter #1
Hello All!

We have just purchased a 1966 Ford Mustang, 289 V8. We know the car was originally a V6 and at some point changed to a V8. So far, we love it! I have noticed a sound when accelerating that I wanted to ask about.

When accelerating, there is a hissing sound that comes from the engine. This doesn't happen during all acceleration or in cruise. We do have to press fairly hard on the accelerator, and the hissing sounds like it's under more pressure as we press harder on the gas.

Any ideas?
 

·
Registered
Joined
·
4,651 Posts
Congrats on the car! Second, Mustang base engine was the I6 (inline) not a V6. The hissing sound is either a vacume leak but most likely what you are hearing is the carb secondaries opening and lots of air getting sucked into the engine....very normal!
 

·
Super Moderator
Joined
·
1,642 Posts
@NickFlightX

Welcome to AFM!
Please read the Site Rules and be sure to complete your account details.
We’re glad you’ve joined us.
 

·
Registered
Joined
·
2 Posts
Agree with Beechkid.
If you want to check if what you hear is the "normal hissing" sound, just take off the air filter housing,
start it up, let it warm up a bit, and give it some throttle. Probably just increased air intake into your carb.
 

·
Registered
Joined
·
6,241 Posts
If it's a vacuum leak it will hiss louder at idle than at acceleration.
 
1 - 5 of 5 Posts
Top