Boost Gauge Vs. dash display

Brett Dikeman brett at
Thu Aug 1 00:14:59 EDT 2002

At 10:09 PM -0400 7/31/02, Zoot531 at wrote:

>Curious eh?  I know I can't explain
>it but it may be good news for those who are not sure if they are making full
>boost...the dash gauge (atleast on my car) seems pretty darn screwy.

You might want to test the condition of the line to the ECU.  I had
several leaks, including one major one that developed during an NEQ
track event.  The green line runs under the fuel lines, at least on
my car...and at the end of the first day I had a -major- leak that
could be heard from several feet away with the engine running and
hood up(one of about a half dozen or so things that went wrong with
the car that weekend/leading up to that weekend, including serious
dents, which Chris helped me pound out the evening before the first
day after we drove up- what a guy!)

This will be especially true if you plumbed the gauge close to the IM
instead of T'ing off the ECU line close to the ECU.  Even if you T'd
off the ECU line close to the ECU, inspect the hose, clamps, and
moisture trap.  Probably the easiest way is to unscrew the ECU from
the mount so you can get easier access to the line, start the car,
and listen with a mechanic's steth or a short length of small
diameter hose(poor man's mechanics steth) along the length of the

Another way is to undo the line from the back of the IM and use a
mityvac(hand vacuum pump) to put vacuum on the should,
without fail, hold a strong vacuum(leave the ignition on and pump it
until you get about .2 or .3 on the display, for example.)

"They that give up essential liberty to obtain temporary
safety deserve neither liberty nor safety." - Ben Franklin

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