When ever I turn on the A/C in my 92's, the whole car begin to shake hard, and the RPM goes down to 300-400, as if the car will die. Pressing the gas or when the car moves, it will calm the car down. Any clues what's wrong with my ride?? thanks.

 

I believe that it suppose to idle up a little when the compressor kicks in to make up for the strain on the motor.You might just need a tune up.Getting any codes?

 

I did a tune up, but it still shakes. There's no CEL on. Should I just manually check the ECU for any codes? Thanks for the reply.

 

Check your grounds-they may have rusted out-all of them. Then check your alternator. Not enough juice.

 

My '92 had lower than normal RPM at 600 when A/C was on.
Having the dealership clean the EGR ports solved that problem. Car has 200kMi. Actually it had a lower idle when A/C was off too. Though I never saw it going down to 300-400RPM.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by neih59 &raquo;</TD></TR><TR><TD CLASS="quote">When ever I turn on the A/C in my 92's, the whole car begin to shake hard, and the RPM goes down to 300-400, as if the car will die. Pressing the gas or when the car moves, it will calm the car down. Any clues what's wrong with my ride?? thanks.</TD></TR></TABLE>

i have the same problem w/ my 94 just the rpm goes down to 600. i thought it was normal.... and what are the EGR ports?

 

A little dip when you first hit it is normal. But it should come right back up. If it dips and brings itself back up you are fine. Hell, A/C is heavy and draws too much power anyway. I say ditch it.

 

Yeah I wish I can forget about the AC, but it's hot here in California. Is there a sensor that activate when A/C is on to raise the RPM? there must be a unit that regulate this...

 

Your A/C kicking on will naturally drop your RPM's, but not that much!!! Like it's been said b4, check your grounds.

 

Which ground should I check? I'm sorry I'm a very newbie. Thanks.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by neih59 &raquo;</TD></TR><TR><TD CLASS="quote">Which ground should I check? I'm sorry I'm a very newbie. Thanks.</TD></TR></TABLE>

All. Anything rusted should be redone etc...

 

nobody has said it yet but the shaking is most likely from worn out motor mounts, replace them or u can just use inserts, however doing both would be best

 

You said that you have low idle, & that the car sakes when you turn on the A.C. . Your idle should be around 700 RPM (+ or - 50 RPM) with the IAC connected, the A.C off & the vehicle in drive (with the park brakke on of course). To set your idle do the following:
1. Disconnect the IAC.
2. Start the engine.
3. Check the idle speed w/ the vehicle in gear, it sould be 550 +- 50 RPM. Somtimes the car won't idle at all if the idle speed is out of adjustment (too low).
4. If adjustment is required first locate the idle air/speed screw, it's located at the left top side of the throttle body under the vacuum lines coming from emission controle box. The idle screw has a seal on it to prevent dust & dirt from getting to it you will have to take a small screw driver & pop the plug out, once you've done that useing a flat blade screw driver you can adjust the idle by turning the screw in to lower RPM or out to increase RPM. It seems in your case that you would what to increase RPM to correct levels to solve this problem (you said you were idleing 600 RPM correct RPM is 700 in drive with the IAC ( Idle Air Controle valve ) connected. Idle with the IAC disconnect is 550. The IAC gets disconnected for adjustment purpses. You will trigger a touble code with the IAC disconncted, have it cleared when you are done with adjustment.
5. After adjustment is complete shut down the engine & reconnect the IAC.
6. After the IAC is reconnected you can restart the engine & check the idle speed, it should read around 700 RPM (+- 50 RPM).


Now turn your A.C on & see if it smoothed it out.

The IAC plays a large part in controling the idle speed, if the idle speed went from 550 to 700 when the IAC was reconnected it is most likly to be working correctly, if the idle speed did not increase when the IAC was reconnected chances are that it is not working correctly.

E.K.