ot180

My 92 sc400 dies if you turn the AC OFF. Ive heard of the opposite before but never this. I recently had the MAF sensor changed out by toyota. Dont know if this has anything to do with it. Any insight?

O. L. T.

iTrader: (17)

Well, turning it off will create a rush of air through the vac lines as the car revs. Dunno what that means though.

ot180

dont know. im at a loss here

np20412

I'd say go get it checked out by someone you trust as a mechanic who knows the car, this could be something difficult to pinpoint. The stealership may have to be an option as well

VJ RC51

welcome to the world of fried ECU's...

soardrft

iTrader: (8)

does your car run without the AC at all? how many times has this happened. mine did that once and after a tune-up it was fine. do you idle very low when the AC is off? my suggestion is check your idle if its low adjust it.

ot180

a bit. just had timing belt changed and they broke the MAF sensor so they installed a new one (metal instead of plastic) its been doing it since then. Yes it idles low when ac is off. RPMs start bouncing a little its so low then it cuts off. When the ac is on the car runs perfect

5spdSC300

iTrader: (1)

Im curious if you even know what your talking about? not trying to flame here but when you post a comment like that if would help the guy if you actually gave him some reason as to why you think his ecu is fried??? i don't even see the car running at all if the ecu was fried but it could as i have never fried an ecu.

ot180: sorry im of no help. that is a very odd problem and i think your best bet would be to take it back where you got the work done and have them take a look at it...especially if its a dealership.

ot180

thats cool. Im gonna take it back (done at local toyota dealership) The question was mainly for my own curiosity. Id heard of the opposite with the AC but never this. Thanks anyway fellas

SC4Million

From what you said it sounds like the idle needs to be adjusted.

When the AC is on the car will raise the idle to compensate for the extra stress of running the A/C compressor.

When you turn it off there is no extra compensation, the idle dips too low. The ECU tries to compensate for this (idle bouncing) but fails and the car dies.

At least thats how I understood the situation.