fazt4life

iTrader: (1)

i have a 91 Z28 5.7 mostley stock with a few things.
If i let it warm up everything goes normally just as it should but the final resting spot for the idle is 1000.
i dont know if this is right or not, it all seems to work perfectly it will idle high just to warm up then it drops down to 1000 and wont go lower.
Where is it supposed to idle at i was thinking around 800 to 850?
is there anyway to change it?
Thanks

91interceptorZ

iTrader: (3)

I believe 650-750 is more accurate.....1000 is too high. you might have an issue with the throttle cable sticking slightly, more likely the idle air control valve, throttle position sensor. Also a vacuum leak could for sure to that....you might have a hose disconnected or broke, or a leak in intake gasket. Vacuum leaks can be hard to find but for sure cause problem.

rgarcia63

My 388 stroker with a starting coolant temp of 186° will start at 1200rpm and ramp up to 1600 then down to 650 and back up settling around 800 in about 17sec at a coolant temp of 184°. My table is modified to idle higher than the 575rpm for the stock bin below.
If you CTS is reading below 100° (when it should be higher) the idle would be in the 1000 rpm range.
The ECM uses a table for idle, this won't be the actual idle, but close.
ARAP 6E.bin
Deg F vs RPM
----------------
306 575
284 575
252 575
241 575
219 575
198 575
176 575
154 600
133 600
111 750
90 900
68 950
46 1050
24 1050
3 1050
-18 1050
-40 1050

DENN_SHAH

iTrader: (1)

if your going by the factory tach, remember they were not the most accurate when they were new and get farther off the older they get.

fazt4life

iTrader: (1)

ive heard about that but it does sound pretty close to 1000 so im gonna start inspecting for leaks and im gonna check out the IAC. i should go get an aftermarket tach and hook it up and see what thats telling me too just to confirm it.

91interceptorZ

iTrader: (3)

oh, like rgarcia posted above, that's correct too.....if you coolant temp sensor is not readng correct.....like telling computer engine is 100 degrees instead of 200 degrees, that could cause a problem too....and if you change that out...rmember there are three temp sensors on the car so get the one forthe computer, lol.

fazt4life

iTrader: (1)

my car does have a chip too. as well as my engine fans on a manual switch inside the car. i turn on the fans once it hits about 175 and it cools its down to about 165 where it stays. i dont know if this would affect anything just throwing it out there.