EGR Corrections

[TBK]

I know on my X-11 with a negative backpressure EGR, the test house has to
literally plug the exhaust pipes and rev the engine to confirm the EGR will
open. Signal to the controller and vacuum will not open it at idle or hi
revs without a load on the engine. He had me hold two shop towels in the
pipes and he reved the engine to 3000. Just as the rags were ready to burst
into flames (and scorch my hands), he let off and said 'She passes'.......
The backpressure in the exhaust is NEVER over 1.5 PSI (stock X11 exhaust
system). So just a little nudge must help it open. If I disconnect it, it is
ping-city at part throttle, so it is working.

I set the EGR enable temp hi to disable it.

TK
-----Original Message-----
From: ECMnut at aol.com <ECMnut at aol.com>
To: diy_efi at efi332.eng.ohio-state.edu <diy_efi at efi332.eng.ohio-state.edu>
Date: Saturday, July 25, 1998 8:21 PM
Subject: Re: EGR Corrections


>In a message dated 7/25/98 10:30:12 PM Eastern Daylight Time,
>nacelp at bright.net writes:
>
><< it seems like this one spark table is a correction for timing
> for egr and runs from idle to 100K/Pa, and up to 4,800 rpm, at 100
> K/Pa.
>   Again this is gm specific, and is there anyone who'd care to
> comment?...... >>
>
>Ayy Captain, you're always on the think...
>The syphoon chip has code that suggests the egr can open under boost
>conditions.  It never occured to me that the exhaust pressure could be
opening
>it from the other side.  Hmm...  Any harm in setting the "EGR enable temp"
>really high, to make sure it is a non-issue, then blocking off the EGR?
You
>have me worried that it may be blowing open when I'm already trying to
fight
>deto under higher (than factory) boost levels.
>Nice cone!
>Mike V.
>