Stalling when AC is on

[Madmax_4a]

Ok I am begining to hate my car. Last weekend I replaced my disc brakes and tested the car, everything worked great no more squeaking or elephant sounds. I drive fri nite and sat no problem....sunday however it was hot, i live in daytona beach, fl and my car died at a red light when I threw in the clutch with the AC on. I turned the AC off and everything worked normally. I turned it on and the car dropped to 400rpm and sputtered then raised to 500 rpm and shook and the belt started squeaking when I rev'd the engine. I turned off the AC and the idle raised to 900rpm and idled normally when I rev'd the engine it did NOT squeak......what the heck is going on here? Please anyone help me!

 

[TalonRacer18]

Dirty tb? When was the last time you replaced your air filter?

 

[Madmax_4a]

I just changed the filter a week ago, KN and reset ECU.

 

[Megaman]

could be a bad alternator

 

[Madmax_4a]

Ok I was playing around with my car last night. First of all it is a 1.8l and I started the car with nothing turned on. Then I turned on the Fan for AC.......the car did not stall! Then I pushed in the COOL button for orange light to come on and the car stuttered went to 450 rpm almost stalled and went up to 500 rpm and shook. As soon as I pressed that button I heard to clicks coming from the box with the AC relays in it, drivers side box near firewall, and same occured when pressed in button for green light. It blows super cold too! PLEASE HELP! Lol I think this car is a nightmare...

 

[TalonRacer18]

That would be the ac button. I dont know why it would stall. Maybe a bad a/c compressor

 

[thehyena]

have you hacked your MAS at all?

 

[Madmax_4a]

When I bought the car the MAS had the big honeycomb removed. I havent had any problems since i bought the car. The car came from a lady around 30 yr old with no kids or husband....according to the title she had the car for 4 years....i do not know who took it out. I saw on a site that you should have a free flowing k and n air elemnt attached and everything would be fine, when I attach my k and n without the air box then the car hesitates and jerks when cruising.....

 

[thehyena]

Originally posted by Madmax_4a
When I bought the car the MAS had the big honeycomb removed. I havent had any problems since i bought the car. The car came from a lady around 30 yr old with no kids or husband....according to the title she had the car for 4 years....i do not know who took it out. I saw on a site that you should have a free flowing k and n air elemnt attached and everything would be fine, when I attach my k and n without the air box then the car hesitates and jerks when cruising.....

that's not true (as i have found) replace the honeycomb.... I have a hacked MAS and a K&N and my car can't idle rightwithout me feather peddling it all the time.... also have you clamped your vacuum tubes?

 

[Madmax_4a]

No i did not clamp a thing. The only thing I have done is installed a K and N in the air box. That is it. and it ran great for weeks untill last weekend. and the problem ONLY occurs when I hit the AC light.

 

[thehyena]

check the belt for the A/C and get your compressor tested. the vacuum tube should be clamped at both ends too. I clamped mine and now my car just idles like shit but it dosn't stall nemore

 

[Madmax_4a]

which vaccum tube are you talking about to clamp??

 

[laserblue]

I am only familiar with a 2.0L, but I think that all throttle body engines use the same stuff------ The idle control motor is supposed to adjust the rpms under varying loads, such as the A/C compressor kicking in. This thing works by opening [or closing] a valve a bit, to allow air to bypass the throttle plate. In fact, I have written to several posters saying that the way to test this idle motor is to turn on the A/C and watch the tach. If it is working, the rpms should dip for a split second and the recover to the original value. And then turn off the A/C and again, the tach should jump up then return to normal idle rpms.
...... So what I'm saying is --> check out that idle speed control thingy! See if you can grab a S/M and find the page where it describes how to test. My '91 uses a different control motor [I think] so my testing procedure may be different, and therefore, I'm not going to describe how to test it...... and mislead you!
Let me know what you find.. That idle speed thingy is a common fault.

 

[TalonRacer18]

Like i said before, i say that it is the A/C compressor.

 

[Madmax_4a]

I went to library and got a book from Chiltons on this 94 laser but it had nothing in it about the ISC. I got my bro in law service manager at Ford to let me borrow the DVD that has the Plymouth service manual in it. Ill get that later today or tomorrow and let you guys know what I find.!

 

[thehyena]

the tube that should be clamped is th etube going from your intake pipingg to your valve cover

 

[turbo eclipse]

i have a similar issue, car runs fine at cold start, even with ac on. but if you drive for 30 minutes at minimum, turn car off, turn car on, it tries to idle around 400rpms so i have to keep foot on gas for a few seconds then it levels out and i can take foot off the gas. And the AC, well, if the car is still hot as described and you try to push ac button for amber or green light, then the car shudders a little, but slowly gets back up to almost regular idle. You never have to worry about getting stuck somewhere, but this problem makes my baby look unreliable to my family members that don't know crap about cars.