hitting fuel cutoff after installing QLCC

[Noah]

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> At 08:04 AM 9/24/2003, Eric and Robert wrote:
>
> >Did your car have any other boost modifications prior to installing the
> >qlcc chip?  If it had the zenor diode modification, you should remove
> >that.
>
> Yes, if present it should probably be removed but the function of the
> zener/resistor mod is to prevent the chip from shutting off the fuel pump
> when boost is elevated.  This can't be the source of the problem.  It
might
> be the source of other problems but not this one.

The car was completely stock before the "transformation". In fact I could
not get more than 1.3-1.4 bar to appear on the gauge. This was pre-boost
gauge though, so it may have been up to factory specs. One thing I have
learned is that the digital gauge is VERY slow to respond. It even seems
like the fuel cutoff is pretty slow to respond also, since it's getting it's
signal from the same source as the gauge.


> >The chip is doing its job in cutting off at 1.95 bar.  That is a
> >designed-in safety feature to keep from destroying anything.
> >
> >It sounds like your wastegate is not opening.
>
> That is a possibility.  A torn wastegate diaphragm can cause overboost.
>
>

I'm thinking that I would have noticed the diaphragm tearing if I did it
while changing the spring, and I know it was fine before I started.

> >Are your hoses to the wastegate OK? Check the lower hose to the
wastegate.
> >Is it attached?  Any cracks?
> >
> >Your spring may be too stiff.  Is your wastgate cap adjustable? If it is,
> >back it off until the problem goes away.
>

I checked the lower WG hose yesterday and found it to be fine.
Before this procedure I had no overboost problems so I'm guessing it mostly
has to do with the spring pressure. I am going to try to find the old stock
spring today and see if reinstalling that stops the overboost.
Maybe I'll make my WG adjustable and try it that way too. I like the
characteristics of the heavy spring but obviously I can't deal with the max
boost it provides. Maybe the heavy spring will be ok with less preload.

Thanks for the help guys =)

-Noah