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A/T 4speed fails, car wont move until hot.
http://www.fixkick.com/IDLE-AIR/dutycycl...html#Begin


low idle has many causes.
and if there is cause, then we fix cause first then set duty cycle.

low idle causes. (besides, isc dead or shut down as yours was)
Cam timing retarded
spark timing same and is cause by cam timing (distrib runs off CAM)
egr leaks.
bleed screw cranked 100% CW closed.
engine running very lean (bogs and power loss, and RPM drops.)
engine misfiring.... (runs slower)

if something is very wrong or 2 things. and engine power is very lacking, the ISC may fail to correct that.
but if the engine is timed, right and power is good, and not misfiring
then the ISC works 100% but in all cases needs to be calibrated,
the duty cycle setting is 50%, yours was NOT.

setting idle duty is last.
read my page to see why , it explains all that.
see the "vast" topic there, what causes the ISC to fail (or lose control)
if engine works perfectly?
then set the 2 pins to 7vdc hot, and be done.
not at the DLC but the ISC pins. (nothing unplugged,) hot engine.

some folks just turn the bleed till 800 locks in, then find it fails in DRIVE, so the fiddle again. and again.
how you do this is your call.
i use a scope.
others use a meter, some meters do work. and some meters newer have a duty mode, and that can work too.

im clueless to this answer

"I see blue/red wire and a black wire."
where might that be?

my guess now, is you have never drove a fully running right sidekick or vitara.?
one that has a working ISC.!

i never would have guessed that. but sure can happen.
that is why i kept asking for accurate RPM numbers!

as you might not know, the ECU is hard coded for 800 exactly (+-50 rpm) hard hard coded,! (hot, a/c off and P/s not in overload)
so if its off more that 50 RPm, then i know the SERVO system is DOWN.

see?
accurate readings matter, on cars.
as is noting that idle regulation is DEAD.

at hot idle regulation works 100% perfect.
even with a huge engine load change, from park to drive.
huge.
if not ?,its broken.

THE PROCESS....
the cold start rpm in about 1500, (Faster in Alaska , IAC rules roost here, the physics of WAX)
the engine runs and coolant warms as coolant nears 150F the IAC goes dead closed WAX expands.
the RPM at 1500 drops slowly as water warms and ISC closes bit by bit. (all by IAC actions....)
Bam IAC is closed.
now only the bleed screw and ISC , supply ALL AIR to the engine, every bit if air, .....
and the ECU goes to ISC servo mode NOW, and when this happens the ECU now commands 800 rpm, this is how it works.
800 exactly hot. and regulates like MAD.
if not , there is a problem.
this servo is a closed loop idle speed control system, and runs at 200 times a second, fast.
the ECU may also (many do) tweak spark timing on the FLY to keep idle at 800 exactly..
so 800 is a magic number, it's hard coded, (and 1000 RPM in idle up mode)
using a real tachometer tool , helps greatly, as the dash tach is OLD and really just a toy, analog tach, seen many lie like mad.
http://www.fixkick.com
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Messages In This Thread
4sp, car wont move cold. - by fixkick - 08-26-2014, 09:21 AM
car wont move cold. - by fixkick - 08-27-2014, 01:54 AM
RE: A/T 4speed fails, car wont move until hot. - by fixkick - 11-11-2015, 11:32 PM

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