420A Loud Clicking Sound From Injectors

[BLACK'98DSM]

At idle I can hear what sounds like a ticking or clicking sound. Upon further investigation I believe the sound is coming from the fuel injectors. I wouldn't be too concerned about this, because I know a slight sound is normal, but the sound is pretty loud. At idle it is the most noticeable sound if you're outside the car.

What's causing this?

 

[jakk220]

Probably a lifter

 

[steve]

That doesn't sound normal. Sure you can hear the injectors click if you open the hood and listen for them but I've never heard them be so loud that they are noticeable with the hood down.

Have you tried using a piece of hose to listen through to localize the sound? If it's the injectors check the fuel pressure and make sure the insulators are in good shape.

 

[BLACK'98DSM]

Probably a lifter

That's what I thought at first but I tried listening around a bit and the sound is definitely coming from behind the valve cover in the intake manifold area.

 

[BLACK'98DSM]

That doesn't sound normal. Sure you can hear the injectors click if you open the hood and listen for them but I've never heard them be so loud that they are noticeable with the hood down.

Have you tried using a piece of hose to listen through to localize the sound? If it's the injectors check the fuel pressure and make sure the insulators are in good shape.

Are you thinking the fuel pressure is too high, or too low?

 

[BLACK'98DSM]

I ask because I've been on the fence lately wondering if my stock fuel pump is shot.

 

[steve]

Not sure which would make a bigger difference just that it's a variable that can change the sound of the injectors and as such something to be eliminated as part of the diagnosis.

 

[BLACK'98DSM]

I never figured out the cause but it stopped after I pulled and then replaced the manifold and fuel rail.