A/T 4speed fails, car wont move until hot.

[fixkick]

500 is wrong! dead wrong, why? . (assumes 500 is real) hot or cold.

that means the ECU can not control idle. the ECU is hard coded to 800, it opens the ISC to raise 500 to 800 RPM in servo loop actions. and holds it there like a rock ,even in DRIVE ! (my guess, is duty cycle set wrong. bleed screw turned 100% CW [closed]
can do that.)
that is right a hot engine can run great with too low of an idle speed, the 800 is EPA dictated, and hard coded, so smog is lowest at that RPM, and CAT lasts the longest (that is 8 year warranty on that part alone) and the trottle reponse is way better at 800 , after all 1/2 the equation for HP is RPM.

simple alegbra.... see how RPM works? rpm x torque see that relationship?

the pedal feels heavy (as in just the pedal) or the pedals demand for power , is weak or slow. (actual throttle action gives weak engine power ?)
if this is a power, issue why not get idle RPM fixed. so HP is there ready to use.


its hard to diagnose any car on earth, deaf blind and not present.. for sure...

even videos dont help cant see drivers feet or road conditions, etc.

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the stock HP at idle is about 15hp. at 800. so if you lower that, much, the HP rolls off fast.. (not to mention supper low air flows, cause the maf to read wrong..
the power at lower rpm is very pathetic.
so needs aggressive right throttle foot action to bet more more power, 300 more rpm more power.

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so.
i have only one question why is the ISC dead. ?

[zukitrek]

500 is wrong! dead wrong, why? . (assumes 500 is real) hot
Hot

that means the ECU can not control idle. the ECU is hard coded to 800, it opens the ISC to raise 500 to 800 RPM in servo loop actions. and holds it there like a rock , even in DRIVE ! my guess, is duty cycle set wrong. bleed screw turned 100% CW [closed] can do that.)
Thats the one thing I have not touched under my ownership. Can try fidling with it, counting turns to see what happens?

that is right a hot engine can run great with too low of an idle speed, the 800 is EPA dictated, and hard coded, so smog is lowest at that RPM, and CAT lasts the longest (that is 8 year warranty on that part alone) and the trottle reponse is way better at 800 , after all 1/2 the equation for HP is RPM.

simple alegbra.... see how RPM works? rpm x torque see that relationship?

the pedal feels heavy (as in just the pedal)
or the pedals demand for power , is weak or slow. (actual throttle action gives weak engine power ?)
yes, feels weak, but then as speed increases feels normal
if this is a power, issue why not get idle RPM fixed. so HP is there ready to use.
Will get to that. I want to fix this already.


its hard to diagnose any car on earth, deaf blind and not present.. for sure...
I know, ill do my best

even videos dont help cant see drivers feet or road conditions, etc.

[fixkick]

the bleed screw is duty cycle, CALIBRATION. spec is 50%
and its 2nd job, is recalibrate if you have minor air leaks. in the induction, (SAY tv BORE WEAR afte 300k miles)
and 3rd is a older tired, engine (weaker) re calibration. (olders engine have weaker vacuum)
the ISC can in fact compensate for leaks, or any weak engine , hands off. that is its job. so long as , ISC not jammed, or huge leaks.(or huge lean)
but you need to keep the duty at 50% hot. (when at 50% 800rpm locks in, in ECU SERVO mode, and is hard coded that spec.)

so, if you unscrew the bleed and like magic the RPM leaps to 800 , that means the ISC just woke up. (works both ways, too fast RPM screw it in)
keep in mind 2 facts.
the ISC can not correct huge leaks. (it can not close more that 100% ) so CANT work with huge leaks, (case in point ruptured brake booster diaphragm)
and the opposite of that is true. if say the bleed is closed 100% the ISC (ecu is brain of that) MAY NOT BE ABLE TO OPEN ENOUGH TO GET 800 RPM.
[i]lazy fingers caps look sorry.[/i

your case is rare here, low RPM. (discounting the huge EGR stuck open issues) most are too high RPM issues.


one easy way to fix this, (assumes nothing major bad)
is to see the DC voltage on the ISC pins to 7vdc running, by turning the bleed screw .
my guess is it will read 12 to 14v now, (wrong)
and you open the bleed screw and as you do the voltage drops. and ISC wakes up.
but keep turning until 7vdc is hit, (some older meters cant do this, too slow , old meters or dirt cheap ones)

suzuki uses a tool you can;t buy. it uses a current mode duty meter, its not made.
but there 3 tools that do work
most nice DMM on DCV volts 20vdc scale.
nicer meters with DUTY mode (on dial)
and all scopes ever made can do 200 HZ isc signal. all can


2 other things cause rpm low and isc dead.
are
lean AFR (will bogs like crazy)
or spark timing set way retarded....

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nut shell:
connect meter.
turn screw for 7v "bleed"
800 happens under software (firm) in ECU, the brain is programmed to 800 hot, (1000 under p/s overload or A/C on) hot.
its unstoppable this once it works,

der bleedn splunken
http://www.fixkick.com/fresh-air/Slide_S...ge_32.html

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things that keep that from happening,
spark retarded.
tps idle switch stuck open for all the ways, even too tight throttle cable and more.
isc JAMMMED
ISC UNPLUGGED ecu.
(massive air leaks some where, only causing LEAN, if you have metered air leaks huge the idle RPMs SCREAM.)

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as I said 500 is Dead wrong. it bet the first thing id notice driving. what's with this John Deer 1900 tractor speeds??(my friend collects them ,funny things to watch, wild !)

[zukitrek]

My DMM is this one:

Craftsman 82140 DMM

   

   

Will this do the trick?

Javier

[fixkick]

i cant hurt
takes minutes to see, yes/no works
what is voltage now.?
can you get the voltage to move lower, with bleed.
can you set it to 7vdc, (with bleed screw)
yes, then set it.
is RPM now 800, sure it is. if not, say where i hangs up.

no dmm (basic ones) are made to do duty cycle, but many do. like 1/2 or more, my guess.
(if it digitizes fast , it can work) most do now.....

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the average of a square wave at 14v at 50% is 7vdc, see? 14v is alternator output, if alt is 14.7v the set it to 1/2 that.
a running average that is..
but if the meter is too slow, iT MISSES all that samples you need to run and average.
that is how it works (A/d converters)

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back probing the ISC pins, hot engine.

[zukitrek]

So test is done back probing ISC? Great will do that after my afternoon commute where shell be more than warmed up.

Ill keep you posted.

Javier

[fixkick]

back probed. yes.
all this does is give the ECU full control of the ISC. (yours is dead)

[zukitrek]

Good morning fix. Im getting ready for testing. I see blue/red wire and a black wire. im guessing positive leads should go on the blue/red wire and neg lead to body ground or to other black wire.

Thanks!!!

[zukitrek]

OK. Got the voltage. ISC was reading 13.77. Then I kept turning screw CCW It was about 2 1/2 turns maybe 3? an idle starting going up until it reached 800rpm steady (started smoking a bit, maybe valve stem seals due cause engine was idling for a while while testing) but ISC reading went to 13.80 steady. Gave her a short drive put in Parking and 800rpm steady on a very warmed up engine.

Hope this is it or maybe need more testing? Now off to work to give her a long test drive and report to you.

Cheers!!

[zukitrek]

that means the ECU can not control idle. the ECU is hard coded to 800, it opens the ISC to raise 500 to 800 RPM in servo loop actions. and holds it there like a rock ,even in DRIVE !

i have only one question why is the ISC dead.?
Dont know if that is the problem. What other test I need to do? I ve done the pinch test (passed), when going from D to N or P idles increases and then normalises and when turning headlights on RPMs blip but then come right up

i cant hurt
takes minutes to see, yes/no works
what is voltage now.? initial 13.77. Did not changed that much after 3 turns, idle yes voltage slightly from 13.77 to 13.81

OK. Now, what happened after driving her a bit longer. On stop lights while in drive and idling RPMs were 700ish on the lower side. The 800rpm were in parking at home after turning bleed screw CCW. I did the short test drive, set her in parking again and 800 steady. But on drive is not holding the 800rpm just like you said in above quote.