Engine sound only on acceleration

[bigfury3]

66 Plymouth fury 318 poly it's my daily driver I didn't drive for 4 days over the holidays and when I drove to work this morning it started to make sound on acceleration like a tfft tfft as idle grows in speed. Engine still runs smooth and fine so I'm thinking it's an exhaust leak anyone have any ideas I wish I could post a video on here so I can show you guys but it won't let me so please let me know

 

[Lefty71]

Easiest way to post videos is on Youtube, then you post a link to here.

Like this;

 

[Lefty71]

Sometimes the broomstick to your ear trick will rule out or confirm internal engine noises, including ticks. An exhaust leak may start to show some carbon evidence if its in a spot where you can see it. You can likely confirm an exhaust leak just lifting off idle listening with the hood open.

 

[bigfury3]

Sometimes the broomstick to your ear trick will rule out or confirm internal engine noises, including ticks. An exhaust leak may start to show some carbon evidence if its in a spot where you can see it. You can likely confirm an exhaust leak just lifting off idle listening with the hood open.

Here is on freeway at 60mph trying to catch the sound on video it only does it on acceleration which I think is just an exhaust leak. Second part of video is idle after hour drive home

 

[carguy300]

Shoot some transmission fluid in the carb while running, look for smoke.

 

[Justin Plant]

Sure sounds like an exhaust leak to me. You might get lucky just snugging up all the bolts. But, if I were a betting man. I'd look for your leak where the pipe meets the manifold.

 

[SIPLOWGUY]

Does sound like an exhaust leak. Look for "black trails" on the exhaust connections.

 

[MONC440]

I find the easiest way to find an exhaust leak is to start the car and restrict the flow by using a glove or a shop towel and hold it over the exhaust tail pipe. Don't plug it totally or you will kill the engine or make more leaks. lol. If it is an exhaust leak it will get louder. You may need an assistant to pinpoint the leak. BTW I always do this when I build a new exhaust system just to make sure I don't have any leaks.

 

[Big_John]

Sounds like an exhaust leak to me too. I'd say manifold to head.

 

[bigfury3]

Yea that's what I thought as well I'm going to try and diagnose it today after work thanks guys

 

[CBODY67]

When we bought our '66 Newport used (from the Chrysler dealer) with 7100 miles on it, it had "more sound" on initial acceleration than when cruising. The dealer tech tightened the exh manifold bolts to the head and all was quiet, all the time. Might be only 1/8 turn on the bolt/nut, but that's all it took. So that is the FIRST place I look for such sounds. Easiest, too.

Just my experiences,
CBODY67

 

[bigfury3]

When we bought our '66 Newport used (from the Chrysler dealer) with 7100 miles on it, it had "more sound" on initial acceleration than when cruising. The dealer tech tightened the exh manifold bolts to the head and all was quiet, all the time. Might be only 1/8 turn on the bolt/nut, but that's all it took. So that is the FIRST place I look for such sounds. Easiest, too.

Just my experiences,
CBODY67

Awesome I'll check it out thank you for the input