Click from dash under load?

[C5aig]

So I had an interesting noise start today.

Under mid-to-full boost I hear a weird click noise that sounds like it's coming behind on the dashboard on the left (driver) side.

The noise does not seem to change with RPM
It does occur every time under the same conditions
It sounds like a click that occurs about 3 times a second
The sounds is like a softer turn signal click
Performance of the truck does not seem effected
Motor is stock

I did a search but didn't come up with anything.

Has anyone had a similar problem?
Where is the relay for boost gauge located?

 

[Fade 2 Black]

Weird. The boost gauge is direct reading from a small nylon tube that comes through the firewall just beside the brake booster and goes to the dash. It could be your turn signal flasher or maybe a relay in the fuse box?

 

[C5aig]

So, what would change, electronically speaking, when under boost versus not?
It's safe to remove the S/C belt and drive around, right?

 

[C5aig]

What if the boost solenoid were acting up?

 

[C5aig]

I disconnected the boost bypass solenoid, hoping it might be the culprit... and no luck.

Still making the same click click click noise.... the noise does change with amount of boost. More boost faster clicks.

 

[C5aig]

Any new thoughts or input?

 

[Fade 2 Black]

Diconnect the line going from the engine bay to the cab and plug it off. See if the noise persists. I don't see how it can be boost related since the factory boost gauge is the only place it goes.

 

[C5aig]

So the noise is slowly getting worse. It's now occurring more frequently and even before boost is being made, but is still dependent on load, and not throttle position or RPMs.

 

[whatwhine]

Stress from torque? i know thats a left field response but the dash could be making noises? i havent heard a clicking like that in mine.....

 

[funair02]

That's a real strange one. Usually multiple clicks in the dash, they way you are describing, are the beginnings of a vacuum leak. Usually it is blend door/defrost related.

 

[my98stang46]

So, what would change, electronically speaking, when under boost versus not?
It's safe to remove the S/C belt and drive around, right?

Yes you can remove the belt and not worry

 

[jaymz]

Might be a loose plug; noise being transmitted thru the dash. Check them quick or BOOM!

Jim

 

[FireGuy]

Might be a loose plug; noise being transmitted thru the dash. Check them quick or BOOM!

Jim

^^^This is the most likely culprit, check it soon.

 

[C5aig]

Noise definitely from engine bay.
The grommet around boost line come off the supercharger and into the dash was pushed into the cab. Put it back to the correct spot and it sounded quieter but still persisted.

I can reproduce the click/tick, barely, by revving the motor from under the hood. Seems to be coming from the back of the motor.

Anyone have the part number, and or know where to get the replacement boost line? Figure that's a fairly inexpensive option to try and see if there's something wrong with the line itself.

 

[C5aig]

I would think a plug would be more consistent, and by RPM related. I can hold the truck steady at 4k RPMs and it doesn't make the noise.

 

[jaymz]

I'm tellin' ya, check the damn plugs, FIRST! It may not turn out to be that, but the consequences of a loose plug are blown out threads and then it's $$$$$$$$$ and PITA.

Jim

 

[chrisheltra]

Plugs or detonation. Specs on tune?

 

[C5aig]

Plugs or detonation. Specs on tune?

stock tune, stock motor

Doesn't sound like detonation to me.

I'm hoping to check and replace the plugs soon... been too busy at work to get any wrench time in.

One other questions... does anyone else's boost gauge register boost when revving the truck in park? My thoughts and experience are that this shouldn't happen and an electrical issue may be at hand.

 

[chrisheltra]

One other questions... does anyone else's boost gauge register boost when revving the truck in park? My thoughts and experience are that this shouldn't happen and an electrical issue may be at hand.

Yes it will.

 

[Fade 2 Black]

The (stock) boost gauge is 100% mechanical, there is a single tube that goes to it reading directly from the pressure/vacuum seen in the intake manifold.

Remove the drive belt from the blower and go drive the truck to see if the noise persists, this will eliminate boost, the blower and some other components from the equation.