legacycentral bbs

ok so ive been messin around with this 92 legacy wagon for a few hours and can't figure this out.

so you have the heat on, and the car idling, press the off button and it stalls.

i changed the ALT, as well as the TCU (had one a few years back that would stall because the TCU was locking the TQ converter at idle)

any ideas?

May have something to do with the compressor clutch. Maybe its is not disengaging when the heater is turned off, or some such thing. Some of the electrical smart people on here will help you.

there is no belt on the A/C compressor and its unplugged.

bad IAC when you change voltage loads, it does adjust idle slightly and I guess your idle control valve just dies at a certain duty cycle. Spray some intake cleaner or pour some seafoam down the IAC tube.

It only happens at idle? Have you tried turning on and off other electrical loads, like the lights? What if the heat isn't on prior to idle?

ericem wrote:bad IAC when you change voltage loads, it does adjust idle slightly and I guess your idle control valve just dies at a certain duty cycle. Spray some intake cleaner or pour some seafoam down the IAC tube.

i thought about that but if it was sticking it wouldn't idle up properly when cold.

evolutionmovement wrote:It only happens at idle? Have you tried turning on and off other electrical loads, like the lights? What if the heat isn't on prior to idle?

i have the lights on and off, as well as the radio on/off and tried other things like the ac on/off.

whenever i hit the buttons it drops rpms no matter what button i hit on the climate control. but it only stalls when i hit the off button.

Maybe it's an "engine off" button.

I'd like to say it would have something to do with a bad temp sensor, but can't seem to figure how that would stall it. I don't know how the wiring would even interact with the ignition/fuel. F'n weird. Has the wiring been messed with at all? PO adding some madtyte system or something?

bone stock

does it do it with every button on the HVAC or only specific ones?
Are there any other things that are strange about the hvac system or heater?
What is the running voltage?

just trying to ask questions that may help to narrow it down.

It may have something to do with the AC idle up. since you have no ac in place and the hvac functions that use the ac tell it to idle up, but it doesnt have the ac load on it, then you tell the ecu to get rid of the idle up by turning off the hvac unit, then it idles down to the point where it stalls.

I guess try resetting the ecu.

anyone know if there is an identifier pin for AC on the ecu that you could clip to tell it that it does not have AC?

I was thinking along the lines of a vacuum leak when you turn it off. Aren't the flappers all vacuum controlled? Am I way off base here?

Jeff

jefferson wrote:I was thinking along the lines of a vacuum leak when you turn it off. Aren't the flappers all vacuum controlled? Am I way off base here?

Jeff

Extremely off base lol haha xD its electronic actuators too I believe.

Yeah, the HVAC doors are electrically controlled.