Have you already checked the infamous cap on the rear manifold nipple?
----- Original Message ----- From: "Matt Bennett" <[EMAIL PROTECTED]> To: "Ray Ayala" <[EMAIL PROTECTED]> Cc: <[email protected]> Sent: Monday, September 15, 2008 7:16 PM Subject: Re: Help diagnosing an intake leak > The original thing I tried was to block off the intake with a dog 'Kong' > modified with an air hose end. Thankfully, my wife thought of the Kong > before I had to go down to the adult toy store and look for what > originally came to mind (Rhymes with 'mutt' plug). Just think of that > conversation- "Honestly, I need the extra large one, for my car!" <yeah, > right, they would have thought". > > I ended up putting the (low) pressure in via the power-brake booster hose. > That did allow me to eliminate that hose and the stuff directly connected > to that- I unplug it from the SC, cover the hose end with my finger, the > hissing goes away. I definitely hear something that sounds like it is > coming from the engine area, but I *really* don't want to take off the > intake manifold, or the SC if I can help it. > > Matt > > On Mon, September 15, 2008 7:15 pm, Ray Ayala wrote: >> 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
