update…..looks like hall sensor malfunction is contributing to poor running
car idles in gear at around 650 rpm….when I Engage the ac the idle drops to around 450 and sometimes lower and at times when arriving to a stop sign the engine will die…starts right back up after I turn the ac off…

like the ac is really lugging the engine down….could the ac which blows cold have an issue and need to be fixed or is it just a brain issue and needs to up the rpm when the brain sees the ac is on and is not responding with increasing idle.

now this car idles at 1100 in park as it should as it was set and does fine…

has the link g 4 extreme brain , cams and itb and ran fine after getting back from precision motorsports and I have a local tuner that is very supportive of the link system so no issues needing a tuner,

just didn't want to bring it to the tuner if it was an ac issue all along….

anybody have any ideas ???

 

When the A/C is turned on it should be triggering an RPM increase to compensate for the drag on the engine. Not sure how to check and ensure it is on your system but have your tech take a look at the programming.

 

that was my next step , but If something specific with the ac is causing more drag the I would like to get that fixed first…. any thoughts.

 

Duh ! I forgot to tell everyone that the ac button on the console doesn't work, ac works only in recirculation mode…. maybe the brain sees only the ac switch to tell the brain to increase engine rpm…hmmmm

sorry could this be causing the brain to not see the ac in use?

 

I used to have that issue, rarely, on the GTS when clutching-in at stop lights with the A/C on. Updating the ST2 software to the newer version with its new Idle Control algorithm allows you to adjust the flow through the ISV depending on whether the A/C is on or not, so no more stalling. I'd have to believe the Link has a similar provision in it somewhere.

Highly doubt there's anything wrong with the A/C, if it's making cold.....

 

Pull the driver's side carpet cover off the center console and make sure the A/C button bar is still plugged in- that connection is not terribly secure. Rule out the trivial first!

 

thanks,,,that may be it…!!!

 

The AC signal to the LH ties in at the freeze switch - so any source of AC triggering will cause load compensation.

Alan

 

thanks Alan, that was one of my questions….glad there are people as smart as you guys around here !!!!

 

update when the tuner looked at it with the computer….the hall sensor was sending weird signals . replacing that as we speak,,,,just odd

any one else ever have a hall sensor cause running starting idling problems?

 

just put over 2000 miles on since hall sensor replacement. no erratic running , or doa at a stop sign…..now in 102 heat putting around in town with ac on car idles spot on 500 rpm in gear taking off from stop sign…

finally have my car back and it is so nice!!!

thanks for everyones help !!!

 

And thanks for the followup!