Tapping

[applehead]

After replacing my serpentine belt I noticed knocking or tapping on the front side, driver side of engine. The 1994 mustang gt has no performance issues. I cant say if the noise started up after replacing the belt or not. Any idea want this could be? I ran a OBD 2 test and no codes popped up.
20260112_105535 (1)

 

[cobrajeff96]

How old is the replacement belt? Was it exposed to the outside elements for a long period of time? Did you inspect it for cracks/tares? Sometimes a deteriorated belt will make this noise, and the frequency of it increases up to a certain RPM until the human ear can no longer detect it (it's usually only detected at idle unless it's about ready to blow to smithereens).

 

[applehead]

This is a new belt from O'reillys auto parts. I will check to see if there are any defects. But the sound seem closer to front top driver side of engine.

 

[RossA81]

Belt might be too long causing the tensioner to bounce on it's stop.

Ross

 

[ttocs]

There is a minor difference between a tap and a tick sometimes and it makes me wonder have you ever heard the noise a bad/shorted spark plug cable makes?

 

[cobrajeff96]

Yea, you should be able to twist the belt by one about 1/2 complete turn. If it can twist a full turn or more it's too loose. Usually you'd hear the belt slipping/squealing if it was too loose.

 

[shovel]

The 1994 mustang gt .... I ran a OBD 2 test and no codes popped up.
20260112_105535 (1)

it's very difficult to run a obd2 test on a 94.

photos or video would be helpful if this is to be diagnosed online.

 

[Terrorist 5.0]

I would check to see if the tensioner is bottoming out, that can make a tapping sound to a sound so strong it gets mistaken for rod knock. Sometimes belts don’t come the right size 100%.

 

[applehead]

Two things.
The new belt I am able to pull up and the tensioner moves pretty easily. But I don't hear any slipping or squealing.
The injectors are original factory installed so I added Chevron concentrated plus fuel system cleaner thinking it may be clogged injector's. Will have to wait for a few miles to see if that helps.
I will be surprised if this works but it is worth a try.
Sparkplug wires show no defects.
Update later.

 

[cobrajeff96]

Could indicate a worn out tensioner. It shouldn't be too easy to deflect the tensioner arm. I mean.....it's right in the name.

 

[applehead]

I'm stupid. What do you mean deflect?

 

[Terrorist 5.0]

He’s basically saying the tensioner shouldn’t move easily by hand since it is supposed to be under tension - hence the name. If you still have the old belt, measure it with the new one to confirm belt size. If they are the same, I would consider doing a tensioner.

Compare how the two feel. If yours is currently bad, you will feel the difference.

 

[ttocs]

simple test, can you slide the belt off of any of the pulleys by hand or even make it move on the pulleys with the smooth edge?

 

[Miltoid]

Spray it with belt dressing to see if it stops, it may just be a spot on the belt.

 

[applehead]

Okay,
I dont know if this link works but this is a nighttime view of bad spark plug wires shorting.
https://www.veed.io/view/e7ff4832-1e1b-4956-8b4e-4b6d8d993190?source=Dashboard&panel=share

 

[ttocs]

the easiest way to test for a short is just to run your hands down them while the car is running. If there is a short, you will know EXACTLY where it is..... They are only electrons and they are really small, it is just enough of a jolt to wake ya up(assuming you don't have a pacemaker).

 

[applehead]

I'm going to replace the plug wires. I'm going to buy some heat shields for the plug wires. I will let you know what the results are.

 

[applehead]

SOLVED!
Bought new Motorcraft plugs. It was late at night so I only replaced the driver side wires. The ticking sound is gone and I see no sparking!
Thank you everyone for the ideas and solutions.

 

[applehead]

I meant Motorcraft spark plug wires. Number 7 boot broke right off from damage from the heat and age.

 

[ttocs]

like I said there is a small difference between a tick and tap. But you will never forget that noise now....