Help with Boost gauge

hinggu

Member
Hi guys,

Experiencing a problem with boost gauges.

I installed a GReddy Profec B and during this time I re-ran all the vac lines with new ones. The Vac line on the Profec is T'd to the FPR and this line is T'd off again to the Autometer Boost Gauge after the Profec B's Filter.

The problem I am having is that once in a while, the car will not read Vaccuum. Both the Profec and Autometer will read 0. If I shut off the car, the gauges will go to -20 hg and then back up to 0. I restart the car and again it will read 0. I drive for a few minutes and the gauges return to normal.

I checked the vac lines for leaks, but none can be found.
Does anyone have any suggestions on what could be wrong?

Thanks
 
maybe your not tee'ed off the right place..


search for boost gauge install and check where they tee off.. mine is on the intake itself..
 
fr0st said:
maybe your not tee'ed off the right place..


search for boost gauge install and check where they tee off.. mine is on the intake itself..

I tee'd off where the boost controller is tee'd off too and i followed the how to for the Profec install.

Weird thing is that it only happens sometimes. Other times everything works fine.
 
could be a vaccume leak or a wastegate that's fixing to be gone. Next time it's at 0 with the car running, take a can of brake cleaner (non flamable) and squirt your connections with it. If the cars tone changes it's your tee's. Otherwise do a search on how to vaccume test your wastegate.
 
hinggu said:
I tee'd off where the boost controller is tee'd off too and i followed the how to for the Profec install.

Weird thing is that it only happens sometimes. Other times everything works fine.

like im no expert here but, if ya tee off where the boost controller is it must not work for the following reason.. what does the boost controller do on the vaccum line? does it block out the vaccum in that section? if it control boost surely it must do something on the line.. i assume you connect the wastegate actuator TO the controller..

so if it blocks the vaccum line in that section for a moment or something like that, and thats where you tee'd off the boost gauge, then i strongly sugest
you tee off on the intake mani where theres a U (up side down) shaped hose thats about 2-3 inch long that connects to the mani from the mani.( you read right)

thats where the guid to installin a boost gauge says to install it.


Fr0st
 
I had mine ran on the same line as the little check valve thingy, and I had the same problems, exactly.

My mechanic just bypassed the valve, and capped it. Perfect now.

Mine would read 0 at start up and run like crap. If I tried to drive it, it would have a reaaaaal loooooong turkey and die. As soon as we changed the lines, no more 0 vac/boost reading.

You're boost controller should be teed between your manifold, and the wastegate actuator only. Nothing else connected, for the best performance.

Route your boost gauge somewhere else, and try to get a clean source, with nothing in between.

Let me know how it goes, because I really think this will solve your problem.
 
Last edited:
get your boost reading from the manifold U-shaped line. just cut in half and insert a T.
 
Thanks everyone for their suggestions. I will try and find a source for the boost gauge. Hopefully that is the problem.

The little U shaped vac hose is running both my recirc bov and HKS bov right now so don;t know if I should tee into that as well.

The gauge is tee'd to the vac line that goes to the Profec's boost gauge, not the actuator/wastegate line. The actuator is on its own vac source.
 
Back