idle problems

[dreadburns]

I recently installed a 20V 4 throttle engine. It works find but for the past couple days when I have the ac on and parked up either in traffic or waiting somewhere the engine idle drops so low that the car actually cuts off. I taught at first it was a one off but it happened about 3 times in the space of 5mins. What can cause this and can I fix it myself?

[Parvin]

Service the throttle body. And if it still doesn't work then the Idle Sensor is going bad.

Having the same issue with my lancer.

[dreadburns]

Could the brain have any problems with this? I original brain was damaged and could not get a new so I had to purchase a refurbished one. Could a engine scan determine the root problem?

[Parvin]

Could the brain have any problems with this? I original brain was damaged and could not get a new so I had to purchase a refurbished one. Could a engine scan determine the root problem?

Good question.

I was given the same advice about the brain being damaged and that's why even when I changed the Idle Sensor on mine it still did NOT work.

The problem is, I ran 3 Scans on the car and NOTHING showed up, not even the bad sensor.

I am yet to test a new brain with the other sensor to determine if it is indeed the brain that needs changing as well.

[dreadburns]

I will try and get the throttle serviced and see if that helps the problem. Hopefully I will find the cause and fix it

[firehead..]

4age 20v noice!!!.

If you gonna get the car scan, make sure and get it done by someone who can read the real time data (temp,throttle %, etc) and not just check for codes. My car had a faulty temp sensor and never threw a code. When i got it scanned a long time ago i was seeing a temp. of -140 degrees. These engines will not throw codes for some sensors etc. I have the service manual for that engine. Let me know if u want a copy.

Could be a bad sensor, check yur vacum lines, and yes service yur throttle body. Dont be alarmed if after you service thr throttlebody it kinda idles high for a while. This settles back to normal in some time.

[subzerounlimited]

are the ac1 and act pins connected to the ecu

[dreadburns]

Honestly I can't say but for some reason it stop cutting off. The rpm sometime drops real low but the step up steps in at the last min and raises the rpm. I have being running the car for about two weeks now so I think I might see if I could do a full service. I also realized that the car idles @ around 850 but you feel the car pulsing slightly. Is that normal?

And firehead if the manual is not too big send me link for a copy.

[subzerounlimited]

when you switch on the air condition the ac1 pin of the ecu is grounded via the ac amplifier. if you ground the ac1 pin of the ecu yourself you will see an idle increase. now you say that the idle is kicking in at the last minute. i cant say for sure if its a short in the ac1 wire or if its the ecu compensating and readjusting the ISCV for base idle. maybe you can check on this and let me know.