idles lean???

[nicku]

My setup is redtop with s15 turbo, nismo 555cc, safc 2 tuned by performance shop, PLX wideband, manual boost controller at 14 psi, stock maf...
everything runs fine all the way to redline, but while idling, the car is lean like 17-19...any idea??

[rightcoastimports]

yea you need to richen up the idle with the afc..

[nicku]

the thing was it was fine before......the only two things i changed were from s14 t28 to s15 t28 and the stock rubber intake tube to the aluminum intake pipe with same diameter.

[nicku]

anybody any ideas?

[louisdaboois]

you may have a little leak around your intake or ic piping. just small enough to idle lean, but not enough to notice a major boost leak. either find the leak or richen it up with the afc.

[nicku]

i tried to spray the carb cleaner around and the boost gauge shows the vaccum at 20...so i thought there was no leak at all

[just1pepsi]

well for some reason it sounds like its getting more air. I'd richen it up.

[louisdaboois]

i tried to spray the carb cleaner around and the boost gauge shows the vaccum at 20...so i thought there was no leak at all

yeah i had the same problem, vacuum was showing great, but i was running like 17-18 at idle and turned out that there was a small leak around the coupler of my hot pipe. luckily i found it with a boost leak tester.

go to home depot and get a rubber coupler of whatever size your hot pipe is and a cap that fits on one end of the coupler snug with a hose clamp. Drill a hole on the top of the cap and shove a valve stem in, with some rtv or epoxy around the edges to ensure no leaks. Then hose clamp the cap on one end of the coupler and attach the other to the end of the hot pipe and run some compressed air through, build about 12 psi (you'll see it on the boost gauge). you should hear/feel air coming out of somewhere. You can also spray soapy water around the coupelrs to see if they bubble.

you should bleed off 1psi at 3-5 secs or so.