Car dies mid shift when A/C is on

[Josh Kushner]

Hey guys,

i have searched for this on here before and found similar problems but not this particular one, my car idles about 2-300 rpm lower when the A/C is on, so when I'm driving and shift at a high rpm, when it drops back down it goes past idle and shuts off while I'm driving. the idle dips when i press on the brake and move the steering wheel, my idle also feels as though it has an occasional kick. i assumed it was the IACV or the alternator so i already went and bought a new, higher amp alternator, it hasn't come in yet unfortunately. any advice to fix the issue would be greatly appreciated!

 

[jetjock]

Does it fast idle on a cold start or idle up when the headlights are on? If so check the AC input signal to the ECU. Quick way to do that is go into diag mode and look for a code 51 with the AC button lit and your foot off the gas pedal. The engine does not have to be running. Verify the code goes away when the AC is off. Might also want to check the dashpot.

 

[Josh Kushner]

when started from a cold start, it hesitates to turn over slightly and then it revs to about 2k rpm and then drops to idle (1k rpm). i haven't noticed it rising in idle when the headlights are on though. and how would i go about reading engine codes on obd1?

 

[Nick M]

He meant 51, not 52.

 

[AbsoluteSpeed]

Here ya go. http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=FI&P=23

Just jump the two pins in the diagnostic box and count the flashes. A paper clip works well as a jumper.

 

[jetjock]

He meant 51, not 52.

Oops. I did indeed. Thanks Nick. Corrected.

...and how would i go about reading engine codes on obd1?

Well, you could RTFM. Or just buy a bigger alternator...

 

[Nick M]

I mistype things all the time on the internet. I go back and look at something and think what the hell is that?