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Can someone answer a simple question for me....

Does the idle on an EJ22 motor go up when the air con is switched on on the factory set up?

I know they do on the old EA motors but their method of acheiving this is rather straight forward.

I can only imagine that if an EJ motors does lift it's revs its through the ECU or possible it simply maintains it's normal idle speed.

Can anyone shed some light on this??

Dave

if it did bring the revs up it would have to do it through the ecu

cant tell ya if it does as my bros car aint here other wise i would

but if no else finds out 4ya i will do soon


tristan

Cool... the question relates to another project im working on... but i sorta need the revs at about 1000rpm.

Dave

why not just rig up an air bleed that bypasses the throttle. Thats how the mpfi ea82 does it and i assume the ej22 does also. The ecu just turns on a solenoid to open an air passage.

this would happen to b 4 the air compressor idea ur wrkin on atm would it

cause would could also fit a hand throttle like some desil cars have only another
idea

LOL no

Dave

On the Outback (EJ25) it kicks up about 100 revs when the aircon kicks in.

Jordan.

Simple answer is yes the revs lift.

BYB-01 wrote:Simple answer is yes the revs lift.

Yep, it does "idle up" as the ac compressor swithches on, i belive its done through the ecu by opening up the iac motor abit more

Awesome so now i just need to find the wire reponsible for this going into the ECU.

Thanks everyone.

Dave

I remember talking to a bloke at a wreckers who'd fitted an EJ22 up to his ea82 car. I believe he's a Qld Suba club member, older guy, Had one of Brett's gearbox adaptors.

Anyway, he used a solenoid somehow to increase revs for the aircon, didn't go into great detail with exactly how it functioned though.

stinky wrote:I remember talking to a bloke at a wreckers who'd fitted an EJ22 up to his ea82 car. I believe he's a Qld Suba club member, older guy, Had one of Brett's gearbox adaptors.

Anyway, he used a solenoid somehow to increase revs for the aircon, didn't go into great detail with exactly how it functioned though.

What he did was use the cruise actuator,very simple.
pin B22 blue wire is th a/c cut wire and C9 blue/red goes to compressor and pin B17 red/blue goes to a/c relay.Are you going to power up a compressor for air tank using the increased idle speed to bring it up pressure quickly?

Im working with the tank but need to see what the working pressure of this compressor is going to be... it seams GREAT when cold cos the idle is a little higher... almost pointless at normal idle though. Looks as though i need to give 12v to one of them wires some how without blowing up the ECU... might see if i can trigger it through a test light... there must be a way.

Probably pin C9.

Dave

The idle up is triggered via the A/C switch input which is 12v in.
The ecu's receives an AC request via this pin and then switches the AC relay coil to ground once it has idled the engine up. It may turn the fans on as well.

It is pin C9 but the colour will vary according to year.

Pin C9 is infact solely to turn the ECU air con fan off so it can be over rid by the air con wiring... idle goes up for about 1 second then returns to normal.

I still have no real evidence there is infact an idle up function on an EJ motor... it seams to simply just regulate it's idle and have the appearance of it raising due to extra engine load.

Dave

SuBaRiNo wrote:Pin C9 is infact solely to turn the ECU air con fan off so it can be over rid by the air con wiring... idle goes up for about 1 second then returns to normal.

Dave

How do you figure this? That's a pretty big conclusion to come to based on the little info you seem to have.

The idle up for the AC isn't like an old L series with a carb, it lifts the idle(via the idle control motor) just prior to the A/C compressor clutch being engaged so it can account for the high initial load then it allows a normal idle after that. The ecu's load sensors(afm, tps etc.) can account for the extra load once it has been introduced, it just needs the extra rpm to prevent stalling when it is engaged. It would work the same with whatever load you are wanting to account for.

If the load you are introducing(you haven't specified) needs a certain rpm to work then you need to either use another means of lifting rpm(air bleed solenoid) or just gear it right so it works at idle.

I came to this conclusion by doing it myself. Seams to be the best way to get accurate information. And from studying numorous wiring diagrams from different workshop manuals... don't confuse me asking a question with me having limited information.

You sound like you must have done it before... introduce a 12v supply to pin C9.... Revs go up slightly as if to simply correct itself in preperation for extra engine load, then returns to normal. Also the fan controled by the ECU WILL turn off... studying the diagrams explains why this is so.

And your right an air bleed solonoid appears to be the only way to make this work.

Dave

I have done it before, lots of times.
That is the folly of the internet, everyone wants to know stuff for free but they don't trust the answers they get.