Aircon stalls the car

[GSR94T]

Hi guys
ive done a search but only came up with this pajero aircon stalling issue:
http://4gtuner.com/site/showthread.php?t=4406
unless im not searching right
in any case i have a 94 cc gsr with vr4 motor, evo aircon unit, gsr ecu and wiring loom.
my air con stalls my car when coming back to idle (clutching in). even if stopped at the lights and you turn the aircon on, itll stall after a minute or so even without doing anything..
whilst driving though, the aircon is freezing cold but what use is that

when the air con isnt on i dont have any stalling issues in any way at all!
I can flog my car and bring it up to 6000rpm and quickly clutch in and itll maintain idle perfect.

when my aircon is initially turned on it also drops idle rather than increasing
i know my idle control unit itself is fine because ive had that changed already for a previous issue and normal driving is perfect. besides with both idle control units this problem has been present.

now i know I can just increase my base idle to like 1300 or something, but from memory this didnt help last summer (ive had this problem a couple of years , and besides i dont really want to drive with a higher idle all day when im not using aircon
my understanding is that the ECU should be kicking up and controlling idle for aircon
These are my suspicions only of what the problem could be:
- aircon wiring or wiring loom for ECU hasnt been wired in correctly ?!
- i know that the 'wax pellet' thing was removed and either a bypass or blockoff plate was used - i have no way to confirm which of the two was done, but could this be a factor in that it doesnt compensate idle quick enough for extra load (aircon) ?

any help or suggestions are appreciated because i know ill have to end up at an auto electrician for some bodge-up job

 

[olly]

don't run air con?

 

[Kane_GSR]

windows down FTW

 

[GSR94T]

gsrs were destined to have air con
dont want aircon, get an rs

ok cmon guys only serious helpful answers being the tech section and all....

 

[3zercrowd]

Out of interest, what type and how do you run your BOV?
Aircon unit/belt alignment ok?

I have had it too and never have gotten it sorted nor have I replaced the ISC motor and I have an aftermarket ecu so its a weird one.
Does it also happen worse while moving the steering wheel?

 

[GSR94T]

hi mate

same problem for you too? sht

im running evo 8MR blowoff valve which is non adjustable plumbback

issue happens regardless if steering wheel is being moved or not.

as for alignment i guess its ok im not really sure on that side of things. it all looks like a straight factory bolt up

 

[Liberoz]

Check terminals - & + are tight on your battery, I had same issue and was loose terminals I have thrown the leads back on and had forgotten to tighten up.
That may help, Give it a try.

 

[GSR94T]

Check terminals - & + are tight on your battery, I had same issue and was loose terminals I have thrown the leads back on and had forgotten to tighten up.
That may help, Give it a try.

tried it no luck

anyone know if the bypass or blockoff plate for wax pellet could be affecting the fast idle for aircon?

 

[marlond]

this happens to me recently idle is normal without aircon.upon checking the resistance of my ISC motor found that 2 terminals giving a higher resistance above 41 ohms than the other terminal so i just pull the deffective coil and replaced it, its done. this happen when my ecu encountered malfunction. this also happened on my friend 4g63t conversion, his ISC motor always break, the cause of breaking is wrong ecu wiring.

HTH.

Check your ISC again..
http://www.vfaq.com/index-main.html

thi

 

[Liberoz]

I know my ISC is on its way out becuase if i hold rpm at 1.5 it hunts up to 2 rpm and back down again to 1.5. The contacts are worn and I would expect so from a 18year old car.

Electrical issues normally get mistaken for being Mechical issues

 

[mannynz]

Maybe your aircon pump bearings have failed.
This will cause the pump hard to turn which causes your engine idle rpm to drop.

 

[Pi3RRo]

i had the same problem and after a while i lost the cold start idle. I took the car to Creatd and the changed my whole throttle body. Since then the cold idle start was fixed and so was the air con.

 

[clone]

raising from the dead.

Having this issue as well as car hunting at idle , not always stalling but on the brink without the aircon, with the aircon she shuts off at light speed when clutch in

 

[Cranked]

Hunting generally indicates a vacuum leak. Do a boost leak teat and see what u find. Alternatively I'd have a look at ur ISC idle speed controller.

 

[unhuman]

Most cars will have a solenoid that will raise the idle when the aircon is turned on, I assume Mitisi's use the ISC as above. I would start there.

 

[bazeng]

There is an Air con switch to the ecu. Might have to confirm that that signal is getting to the ecu as it bumps idle up top compensate additional engine load.

 

[clone]

Checked the ics and ohms are good across all the coils, the signal is reading on the haltech and I can manually operate it.

So signal is goos

 

[JayRome]

There is an Air con switch to the ecu. Might have to confirm that that signal is getting to the ecu as it bumps idle up top compensate additional engine load.

+2

 

[bazeng]

Ah you have a haltec. Ensure your air con request is activated and that when your press your a.c. switch the ecu sees it. Then also the output goes to your compressor to turn that on. Plus set the haltec to open the idle valve when triggered.

 

[Cranked]

Isn't there some stupid wax pellet in the ISC?