Outer Limits 4x4 Board

Installed a VDO 0-30psi boost gauge on a TD.

When off boost (and also slowing down) I get an internal rattle/ticking in the gauge. When accelarating (and boost is climbing) or sitting at a steady speed then it goes away.

I think that it must be engine noise being transferred through the tube??? Anyone else had this?

Yep, mine does the same. Like you i guess it's either engine noise or pressure pulses vibrating the inside of the gauge.

I have heard you can get a restrictor or something to put in the line and stop this but have no other info. I'll be interested if anybody has a fix cos it's pretty annoying but i'm slowly learning to ignore it.

Dave

You using copper tube or plastic?

mike_nofx wrote:You using copper tube or plastic?

Plastic - VDO kit.

I think you'll find the gauge is trying to go into negative (vacuum) territory. Our Cruiser used to do the same thing.
After improving the air intake piping it stopped doing it. If you've got any way of getting the motor to breathe better, K&N, bigger pipes etc, try that.... or a fully sik boost gauge that does positive and negative.....

The problem you have is common with VDO boost gauges. Put a restrictor in the line and it should fix the problem. Should be able to pick one up from repco.

I had/have the same issue.
I soldered up the hole in the brass fitting for the boost line(the fitting that goes into the intake crossever pipe) then drilled it out again with 1mm drill bit. Reduced the problem a lot but still does it when I back off the throttle and engine decelerates after being at full boost.

Was really loud initially, but is much quieter and I hardly notice it when it does it now.

Gauge still responds quickly to changes in boost.

I just figured it was pulseing of air pressure through the line? Oxy/acetyline(sp?) guages do the same thing at high flow rates too.

before and after

80's_delirious wrote:I had/have the same issue.
I soldered up the hole in the brass fitting for the boost line(the fitting that goes into the intake crossever pipe) then drilled it out again with 1mm drill bit. Reduced the problem a lot but still does it when I back off the throttle and engine decelerates after being at full boost.

Was really loud initially, but is much quieter and I hardly notice it when it does it now.

Gauge still responds quickly to changes in boost.

I just figured it was pulseing of air pressure through the line? Oxy/acetyline(sp?) guages do the same thing at high flow rates too.

before and after

THANKS!!!

no worries

I was to lazy for anything like that .. I zip tied an old neoprene stubby holder around the back of mine ..

Shut it up enough so I could not make it out over the myriad of other noises the dudlux made.

Maybe try a few drops of blinker fluid...

BEU77y wrote: K&N, bigger pipes etc, try that.

Post of the week for mentioning K&N in an ISUZUROVER thread as a solution

the VDO gauges normally come with an inline restrictor that goes into the brass fitting in the gauge.

Or you can try a plastic dial from a fish tank that will limit flow.

With boost you are measuring pressure not flow so you dont need to worry about how restrictive the fittings are.

Gwagensteve wrote:

BEU77y wrote: K&N, bigger pipes etc, try that.

Post of the week for mentioning K&N in an ISUZUROVER thread as a solution

What others have said, an inline restrictor fixed mine when it made the exact noise you've described. The local vdo dealer gave one to me.