I am really messed with this IAC valve thing. My car has rotery solenoid valve as IAC. RSC coil for closing side and RSO for opening side. ECU provides a PWM to one and inverted to the other. (i.e. If RSO gets PWM with 75% duty cycle, RSC gets its inverted PWM which is 25%. This makes a resultant force to IAC open 50%.)
My data sheet gives the RSC and RSO values attached herewith. Please see picture 1.You can see resultant of IAC is at idling with no AC, is "closed".
But when I check it in my car, the resultant of IAC at idling with no AC is, "opened". Please see picture 2 & 3.
Picture 2 is RSO. Picture 3 is RSC. ( eventhough it should give inverted to each other please disregard it since it's an issue with oscilloscope.i.e. time shift does not shown by oscilloscope.)
1) I checked for vacuume leaks and none found.
2) I also checked these RSC, RSO values at different throttle adjusting screw setting. No change.
3) Checked IAC with values in datasheet and it was OKAY.
4) Also I checked idling speed which is at around 750 rpm.
5) Also I checked rpm when AC switched on which is increased from 750 to around 900.
Pic 1 - first two graphs are RSO and RSC without AC.
Pic 2 - RSC without AC
Pic 3 - RSO without AC
What is the issue in my car? Why can't I get the setup in the datasheet?
I'm going to buy a car in SL for 2 mil while being in Germany. Then I'm going to put up a public raffle draw and pick one lucky winner to gift that car when I have 600 participants registered in the raffle draw. Registration fee for each participant is Rs. 5000/-
Why didnt I think of this before
So for a spirited convo like this old times; ?BYD
My father has gone ninja about getting one, despite being the new hype/fad here these are common across the world and I've seen a few cross 100,000km in Nepal and Australia.
Seal - Looks nice, very premium interior but too low for my applications
Sealion - Very Premium, feels very well built, BUT that 1.5L on that reasonable chunk of car with a measly 18KW battery seems like a recipe for trouble, incase they sink in value at least the fuel economy must justify that (They say it's a BYD engine - though the lore is it is a hyundai engine)
Atto 3 - Most sold from their lot apparently, common af, Seems to be the best bang for buck IMHO, Its electric since BYD is famed for that, Interior is kinda good, the thing is larger than a vezel but not too large like the Sealion, cheap mobility I guess with less things to go wrong
Dolphin, almost a smaller atto and again too car like and not suited for my application.
JK nailed it on the price and distribution but the only guaranteed thing here is the lot are gonna muck up the aftersales. The Kandy center staff behave like the crew from a Govt. post office.
What are your thoughts and opinions? Could this be the next Wagon R or is this a passing fad like the Micros of 2000s-2010s?
I have an empty parking slot at home previously occupied for 6 years by the starlet and 3 months by an AD wagon -what would be a bang-for-the-buck fun shitbox? Preferably auto as I live in a crowded suburb that has sapped the joy of stick shift out of my system.
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Dear Experts with my all the respect,
I am really messed with this IAC valve thing. My car has rotery solenoid valve as IAC. RSC coil for closing side and RSO for opening side. ECU provides a PWM to one and inverted to the other. (i.e. If RSO gets PWM with 75% duty cycle, RSC gets its inverted PWM which is 25%. This makes a resultant force to IAC open 50%.)
My data sheet gives the RSC and RSO values attached herewith. Please see picture 1.You can see resultant of IAC is at idling with no AC, is "closed".
But when I check it in my car, the resultant of IAC at idling with no AC is, "opened". Please see picture 2 & 3.
Picture 2 is RSO. Picture 3 is RSC. ( eventhough it should give inverted to each other please disregard it since it's an issue with oscilloscope.i.e. time shift does not shown by oscilloscope.)
1) I checked for vacuume leaks and none found.
2) I also checked these RSC, RSO values at different throttle adjusting screw setting. No change.
3) Checked IAC with values in datasheet and it was OKAY.
4) Also I checked idling speed which is at around 750 rpm.
5) Also I checked rpm when AC switched on which is increased from 750 to around 900.
Pic 1 - first two graphs are RSO and RSC without AC.
Pic 2 - RSC without AC
Pic 3 - RSO without AC
What is the issue in my car? Why can't I get the setup in the datasheet?
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