Idle weirdness question

Tuning concepts, methods, tips etc.

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Cla141A
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Idle weirdness question

Post by Cla141A »

hi all i write here so i don't have to open a new post

someone is expert to tune idle with pwm 4 wire valve?( it has 1 inj on throttle body, 4 cyl petrol engine)
i have this on my car , and the idle bounce..
the autotune tuning the idle very high so i manually change che ve table but write 0 in most cell without solve problem :?

request fuel is properly calculated , and inj parameters are right

thanks for support ,sorry for my poor english !

bye
Ms2 v3 Blue Board - Extra code updte
Wasted Spark, Stepper idle -> No clock, led, pwm flyback circ. , Pullup resistor, trigger off coil neg. term. ->F.E.T. protection circ. -> Vr, Hall, Opt. circuit -> Vr Jump -> Std flyback ->Dual Map, Table -> Launch control -> Tacho Out
Matt Cramer
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Re: Idle weirdness question

Post by Matt Cramer »

All 4 wire IAC valves I've seen have been steppers. If you have wired it up as a PWM valve, that could be your problem. If this really IS a 4 wire PWM IAC valve, please post a detailed description of how it works, as I've never heard of such a thing but it could theoretically exist.

I would recommend seeing our article on idle tuning:

http://www.diyautotune.com/tech_article ... uning.html

And this one on stepper valves.

http://www.diyautotune.com/tech_article ... r_iac.html
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Cla141A
Helpful MS/Extra'er
Posts: 99
Joined: Mon May 27, 2013 8:02 am
Location: Messina, Italy

Re: Idle weirdness question

Post by Cla141A »

thanks for the answer :D

i have a 4 wire stepper valve
Image

i ll reading the articles , thaks !
Ms2 v3 Blue Board - Extra code updte
Wasted Spark, Stepper idle -> No clock, led, pwm flyback circ. , Pullup resistor, trigger off coil neg. term. ->F.E.T. protection circ. -> Vr, Hall, Opt. circuit -> Vr Jump -> Std flyback ->Dual Map, Table -> Launch control -> Tacho Out
Cla141A
Helpful MS/Extra'er
Posts: 99
Joined: Mon May 27, 2013 8:02 am
Location: Messina, Italy

Re: Idle weirdness question

Post by Cla141A »

ok my car now run on idle at 15.2 about ( i set the afr table for this , a little economy) and work well

the problem is that the idle is on 1100 1200 rpm , instead 600-800 as requested :lol: the afr is ok , the stepper idle valve is fully closed (0 steps) so i don't know how lower the idle.. in this cell the advance is about 22°, 20-30 kpa row (1200 rpm)
PandaTune.msq
thanks a lot for your time :D
Ms2 v3 Blue Board - Extra code updte
Wasted Spark, Stepper idle -> No clock, led, pwm flyback circ. , Pullup resistor, trigger off coil neg. term. ->F.E.T. protection circ. -> Vr, Hall, Opt. circuit -> Vr Jump -> Std flyback ->Dual Map, Table -> Launch control -> Tacho Out
Matt Cramer
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Posts: 17499
Joined: Thu Apr 16, 2009 8:08 pm

Re: Idle weirdness question

Post by Matt Cramer »

Check for a vacuum leak and see if the throttle can close any further.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Cla141A
Helpful MS/Extra'er
Posts: 99
Joined: Mon May 27, 2013 8:02 am
Location: Messina, Italy

Re: Idle weirdness question

Post by Cla141A »

ok , the throttle has stop screw , but i can't change that registration because car has to run with std ecu..

maybe a wrong stepper setting??? in idle warmup duty step graph the value start from 57 and finish to 0

maybe with new firmare the count is inverted, an i run at idle with fully open stepper?????
Ms2 v3 Blue Board - Extra code updte
Wasted Spark, Stepper idle -> No clock, led, pwm flyback circ. , Pullup resistor, trigger off coil neg. term. ->F.E.T. protection circ. -> Vr, Hall, Opt. circuit -> Vr Jump -> Std flyback ->Dual Map, Table -> Launch control -> Tacho Out
Matt Cramer
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Posts: 17499
Joined: Thu Apr 16, 2009 8:08 pm

Re: Idle weirdness question

Post by Matt Cramer »

Make sure you are using enough retract steps.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Cla141A
Helpful MS/Extra'er
Posts: 99
Joined: Mon May 27, 2013 8:02 am
Location: Messina, Italy

Re: Idle weirdness question

Post by Cla141A »

ok this is the question
the stepper motor close idle air flow when it open almost fully

now start from 57 steps and goes to 0
if i put 150 steps the car accelerate a lot and leaning afr , so 0 is the minimum ( i think almost fully opened, closing the air flow)

when stepper goes to 0 the car stay steadly at 1200 rpm at stoich

about air leak it think that is all ok because with stock ecu it goes very well

may i have to lean a lot afr????

help....... :cry:
Ms2 v3 Blue Board - Extra code updte
Wasted Spark, Stepper idle -> No clock, led, pwm flyback circ. , Pullup resistor, trigger off coil neg. term. ->F.E.T. protection circ. -> Vr, Hall, Opt. circuit -> Vr Jump -> Std flyback ->Dual Map, Table -> Launch control -> Tacho Out
Cla141A
Helpful MS/Extra'er
Posts: 99
Joined: Mon May 27, 2013 8:02 am
Location: Messina, Italy

Re: Idle weirdness question

Post by Cla141A »

i have solve the problem , just tweaking the home steps

but i suggest to improve stepper knowledge, maybe with a good tuning settings , always me and some friend with EU cars are confused about open and closed concern......
Ms2 v3 Blue Board - Extra code updte
Wasted Spark, Stepper idle -> No clock, led, pwm flyback circ. , Pullup resistor, trigger off coil neg. term. ->F.E.T. protection circ. -> Vr, Hall, Opt. circuit -> Vr Jump -> Std flyback ->Dual Map, Table -> Launch control -> Tacho Out
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