low idle... like really low

sgt.stinkfist · 09-27-2011, 11:09 PM

after switching my throttle body and TPS to fix a prior issue, i have seemed to developed another.

upon initial start up, the engine idled as low as an engine could probably idle. i had to hold the throttle to keep it alive, with fast foot work i managed to give it enough gas for me to jump out and grab the throttle by hand before it died. with the idle adjust screw backed all the way out, the engine will hold an idle at around 500-600rpm. if i unplug the BAC the idle may drop by less than 100rpm, and grounding the initial set coupler seems to do absolutely nothing. the engine didnt/doesnt idle rough, just super low and smooth. the only other way i can raise the idle speed is by physically adjusting the throttle stop screws, which i would like to avoid as that seemed to cause the last problem that i recently fixed by using this new TB.

the TB spacer plate flows fine through the port that the idle speed screw bypasses air through, as well as the passage in the TB. i havent been able to find any vac leaks. plugs, wires, injectors and FPR are less than 300 miles old, TPS is set to 1.00v and idle A/F is 13:1 give or take .2. the only thing that seems out of place is timing. when leading is set dead on at the yellow 5ATDC, the trailing is at ~12ATDC or half way between the yellow and red marks and obviously as far as i know you cant independantly adjust leading and trailing ignition timing with the CAS

any light somebody can shed on this will be much apreciated. normally ide be fine with a solid idle of 600ish rpm, but my alternator doesnt even try to charge until 800+ rpm, so night driving make me worried if i sit at a light too long as i can watch my car run on just battery voltage

09-27-2011, 11:09 PM	#1
sgt.stinkfist The Newbie Join Date: Jun 2011 iTrader: (0) Posts: 16 Rep Power: 0	low idle... like really low after switching my throttle body and TPS to fix a prior issue, i have seemed to developed another. upon initial start up, the engine idled as low as an engine could probably idle. i had to hold the throttle to keep it alive, with fast foot work i managed to give it enough gas for me to jump out and grab the throttle by hand before it died. with the idle adjust screw backed all the way out, the engine will hold an idle at around 500-600rpm. if i unplug the BAC the idle may drop by less than 100rpm, and grounding the initial set coupler seems to do absolutely nothing. the engine didnt/doesnt idle rough, just super low and smooth. the only other way i can raise the idle speed is by physically adjusting the throttle stop screws, which i would like to avoid as that seemed to cause the last problem that i recently fixed by using this new TB. the TB spacer plate flows fine through the port that the idle speed screw bypasses air through, as well as the passage in the TB. i havent been able to find any vac leaks. plugs, wires, injectors and FPR are less than 300 miles old, TPS is set to 1.00v and idle A/F is 13:1 give or take .2. the only thing that seems out of place is timing. when leading is set dead on at the yellow 5ATDC, the trailing is at ~12ATDC or half way between the yellow and red marks and obviously as far as i know you cant independantly adjust leading and trailing ignition timing with the CAS any light somebody can shed on this will be much apreciated. normally ide be fine with a solid idle of 600ish rpm, but my alternator doesnt even try to charge until 800+ rpm, so night driving make me worried if i sit at a light too long as i can watch my car run on just battery voltage __________________ 82 GS- GSL rearend, ported S4 13b, MSD 6AL, walbro 255, 460/550cc injectors, 2" dual exhaust, 3 row aluminum radiator w/ taurus E-fan 85 20v ST AE86 - sold to fund the 82 86 RX-7 GXL - donating parts to the 82 everything else - scrapped to fund the 82