Have you tried simply blocking off the SC inlet to see if there's still enough intake air to idle? On a TB I use a jar lid with a molded-on gasket as a cap but have never personally tried it with an SC inlet.
----- Original Message ----- From: "Matt Bennett" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Monday, September 15, 2008 7:42 AM Subject: Help diagnosing an intake leak > After what Ray pointed out to me (below), I looked at some old DLL logs > and saw that my Idle MAP reading that is now about 70 used to be in the 40 > range. So I slapped myself around a bit and started to look for a vacuum > leak. I haven't found anything particularly bad. > > Anyone have any tip or tricks on looking for an intake leak? I tried > pressurizing the intake to a few PSI with my compressor and listening for > hissing, but it has been really hard to localize- possibly going through > an open intake valve?. One thing that I was wondering- how much of the > stock 1.8l engine's cycle has all of the intake valves closed? I did find > a better place to put the fuel pressure regulator's vacuum hose, but > wiggling stuff around hasn't brought me any closer to bringing the vacuum > down to a more appropriate value. > > Regards, > > Matt > '96 with prototype Ubercharger > > > On Sun, September 7, 2008 1:12 pm, Ray Ayala wrote: >> The log shows the idle switch signal on even when the map signal show >> that >> either the throttle is open or there's a big intake air leak. The idle >> switch signal kills the fuel completely when rpm is above the idle >> control >> range (~1850 rpm). >> >> >> ----- Original Message ----- >> From: "Matt Bennett" <[EMAIL PROTECTED]> >> To: <[email protected]> >> Sent: Saturday, September 06, 2008 7:39 PM >> Subject: Bucking, DLL help >> >> >>> Howdy folks, I'm trying to figure out my latest issue, I seem to >>> remember >>> this type of problem being discussed before, but I didn't take adequate >>> notes. Right now, the most annoying problem I have is that my car has >>> some very abrupt on/off transitions- also the "idle oscillation" is >>> pretty >>> bad. You can see both of these characteristics in this (really long) >>> log: >>> >>> <http://www.hazmat.com/~mjb/projects/miata/DataLogs/2008-09-06a.bin> >>> >>> The vitals on this car: >>> 1996 with prototype Ubercharger (intercooled, with air temperature >>> sensor) >>> 550cc Injectors >>> Vishnu Dual feed fuel rail >>> Link ECU (non OBD- I believe that this is referred to as a 94-95 Link) >>> AEM WB02 >>> Stock engine internals >>> Setup for (but not installed) NB02 >>> >>> >>> Another thing I'm thinking of- I realize that tuning on the road is >>> difficult, dangerous, and often runs afoul of the law- has anyone >>> created >>> a script for the most cost effective way to use a dyno? The one that I >>> can rent time on is a brake dyno (not a Dynojet). I want to tune for 1) >>> emissions and 2) power with drivability- and 1 and 2 don't have to be >>> the >>> same map :) >>> >>> The vast majority of the adjustments appear to be with fuel- is it >>> because >>> changing fuel zones is easier and more effective than adjusting timing? >>> Or is timing just a lot more dangerous to play with. >>> >>> With the 94-95 link, can I have both WB and NB O2 sensors logged? I >>> realize only one will actually be adjusting settings. If I tune for one >>> sensor, will I need to change maps when I move between sensors, or can I >>> just do it through the Link keypad? >>> >>> I realize I need to sit down with the tuning manuals from FM- I went >>> looking on Flyin' Miata's site and didn't find the Link tuning manual- >>> I've got an old copy- what is the latest revision? >>> >>> Regards, >>> >>> Matt Bennett >>> Austin, TX >>> '96 with prototype Ubercharger >>> _______________________________________________ >>> Miatapower mailing list >>> [email protected] >>> http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower >> > > > > _______________________________________________ > Miatapower mailing list > [email protected] > http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower _______________________________________________ Miatapower mailing list [email protected] http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower
