dying and weird reving

[NinjaWarGod]

When I turn my car on and the air conditioner is on, my car begins to start reving up and down and the car begins to shake, when i turn the a/c off the problem stops; also, sometimes when i turn my car on it just dies on me and i have to give it a little gas to allow it to run properly (this is also when the a/c is on). My check engine light comes and goes. Any ideas or clues? 95 galant 2.4L
Thanx for any help.

[BlankMan]

First thing that comes to mind is the Idle Air Control valve. This is what controls you engine when going from no-load to under load - like when the A/C engages. It's also responsible for setting the engine straight when you first start the car or put it in to gear. You could try cleaning it first - but a replacement might be needed.

Check first if all vacuum hoses are connected right - you could get the same symptons from a vacuum leak.

J

[brandon]

Did you get the CEL codes read?

[Livn2sk8]

any pics of the the Idle Air Control Valve? Or where it's located, mine did that last week a few times...haven't tried the A/C since.....gas prices are too high anyways...thank God for windows!!!

[NinjaWarGod]

I found the location of the Idle air control motor, The IAC motor is usually mounted on the throttle body. Sorry i dont have a pic of it, and i have yet to try and take it out and clean it but when i do i will reply back with the results. I hope like heck it works.
This is from a book :The IAC contains a built in position sensor which detects the amount of opening of the motor. The position sensor outputs a pulse signal that the PCM receives and uses to adjust the motor to properly maintain the correct idle speed of the engine. Place a stelthoscope on the IAC motor. Have an assistant turn the key ON with the engine OFF, and listen to the IAC motor. Several clicks should be heard as the stepper motor moves. If the clicks are heard, the driver in the PCM abd the circuit are OK, If the driver and circuits test OK, detach the connector from the IAC motor. Using an ohmmeter, probe the connector on the IAC motor, NOT THE WIRING HARNESS> between pins. Resistance should measure between 28-38 ohms. If the resistance values are different replace the IAC motor. Test the other resistance between the other pins and it should measure between 28-38 ohms. If the resistance values are different replace the IAC motor. "

Or you could just clean it like BlackMan said.

Good luck, because I know that I will need it when I start trying to fix it.

[BlankMan]

...like BlackMan said..

Who? LOL

Let us know how it turns out.

J

[Livn2sk8]

from BLANK to BLACK!


hahaha, thanks for the info Ninja....one more project to add to the list for this weekend!!!

Happy Friday!!!

[JiP]

It depends on the year the 97+ use servo motor for the IAC and you wont be able to measure the resistance between the pins to verify if the motor is working. There is also no way to replace just the motor in this type of setup you have to replace the entire IAC assembly. Wich is a pain in the ass to get apart off the TB.

I am not sure about the earlier galants but the 1g/2g ISC is a stepper motor and you should measure around 25ohms between each of the 4 coils. You can replace just the motor itself and it comes off the IAC assembly easily with the TB still on the car, makes it easy to clean the motor shaft and passages.

[NinjaWarGod]

Sorry BlankMan I just saw your pic and wrote down blackman

[Livn2sk8]

Hopefully Cleaning it, will do the trick for you. I priced a BRAND NEW IAC, and keep gettin results of OVER $200 .....soo, unless you go "used", which I hate to do.....man oh man...that's alot of money for that damn thing....

did you clean it? get any results???

[JiP]

Hopefully Cleaning it, will do the trick for you. I priced a BRAND NEW IAC, and keep gettin results of OVER $200 .....soo, unless you go "used", which I hate to do.....man oh man...that's alot of money for that damn thing....

did you clean it? get any results???

I got my 7g IAC assembly worked perfect...swapped it for the 2g isc when I head/ecu swapped. PM if you need it..

[Livn2sk8]

Well, I pulled it this morning, cleaned the crap out of it, and my TB. All shiny on the inside. I couldn't really take apart the whole IAC assembly, but I cleaned what I could as much as I could. It is still "clicking" (as my manual puts it) when I turn the key to the ON position (without starting the engine), so i'm assuming it's at least in working order. Maybe this isn't my problem. I just can't seem to use my A/C, without my idle dropping to damn near nothing....I'm talking 300rpm.....car will run fine with it on, but if I come to a stop sign, it almost shuts down with the A/C on. Once I turn it off the A/C....the idles go back to perfect.....which is fine..but I just wanted to make sure this wouldn't reflect in any other area of my care...as a problem...

[JiP]

Well I'll tell you this...I dont have an isc hooked up. Havnt for months, I adjust idle via BISS and thats that. When I kick the A/C on my idle drops ~50rpm. I cant however cold start the car with the A/c turned on, I cant turn the a/c on until after about 2 minutes of idling right after a cold start wich still is damn good for no isc.


rob

[rfpa1]

If you unplug the wire that feeds the IAC, arent you supposed to get a CEL.

If you do, how you handle it.

How you explain when taking it for inspection.?

[Galant95]

i have the same trouble on my G, same year and what i did, cleaned the TB and IAC as much as i can, BUT i adjusted my throttle cable so when i start my car, my rpm is @ 1000 and when i turned my A/C on, it would drop to about 600-700rpm. works for me, might work for you guys!

[Livn2sk8]

i'm not good with all the abbreviations...what's the ISC?

[BlankMan]

ISC = idle servo control
IAC = idle air contol
really, both the same - at least as far as this post is concerned...

But wtf is a "BISS"? LOL

J

[pinoyesv6]

<div class='quotetop'>QUOTE(BlankMan)</div><div class='quotemain'>

But wtf is a "BISS"? Â*LOL

J</div>

base idle set screw

[JiP]

<div class='quotetop'>QUOTE(rfpa1)</div><div class='quotemain'>If you unplug the wire that feeds the IAC, arent you supposed to get a CEL.

If you do, how you handle it.

How you explain when taking it for inspection.?</div>

Yes you would get a cel, but I use a 95 eprom ecu and it doesnt show codes for ISC. Galants dont have and ISC they have an IAC, the ISC (Idle Speed Controller not servo!) Is not a servo motor like the IAC is its a stepper motor and you can replace the motor with resistors from radioshack and the ecu will think its all functioning normally and won't trigger a cel, unless you have a 95 eprom then you dont need to do anything it just doesnt give a code for that.

As for inspections I dont go for them. And even if I did they dont hook your car up to an odb scan tool in NY so, if you did have a CEL on you can just pull the bulb out of the dash and boom no more cel they just throw you on the dyno and if you pass the snif u pass.

As for changing your throttle cable to adjust idle speed thats just silly..use the BISS.

[NinjaWarGod]

sorry guys that i havent got back to yall with the results, i havent had the time to take the throttle body off and clean it. But, I promise that when I do I will inform yall ASAP. Thanks for all the help and information that yall have given to me.