Hey guys. I know the issue of low idle on GS4's has been discussed many times. I previously had a 98 GS4 and now have a 99, and both have had the low idle issue, but only with the A/C off. For the most part, my climate control is on year round, so I never have the issue. Has anyone experienced the low idle problem with the climate control on? I was driving around today with the climate control on and noticed that the idle RPM (which is usually around 600) fell to around 400 and the car was starting to shake a bit. I turned the car off, and everything seemed fine when I started it back up. This happened once a few weeks ago too. Has anyone experienced this?

 

did you have the ac button pressed? if I have my climate control on the idle is fine. if I push the button to turn off ac but leave climate control running, it will idle low.

 

have you checked your throttle cable to see if it is really loose? if so, you can tighten that and sometimes this helps w/ the idle.

 

Hey Chuck. Yes, the A/C button was on, as it always is, but it was really cold out today, so I doubt the compressor was actually kicking in. Do you think that would make a difference? I doubt it, because I'm sure I would have noticed the issue before either on this car or my other GS.

I've never checked it. There's a whole thread about low idle and tightening the throttle cable (thanks to BananaGS), but I don't want to screw around with it if I don't have to. Do you know whether the throttle cable is exposed or do you have to remove the engine cover to get to it? Hey, wait a minute. I thought you sold your GS and got a MB S-class. [EDIT -- Dohhhh I just saw your sig.] You're still hanging around CL, huh?

 

You DO have to remove the engine cover to gain access to the 2 cable nuts. One nut is on each side of a bracket the cable goes through. The cable attaches to the bellcrank. If there is slack between the cable end and bracket, it should be adjusted by loosening the outer nut and turning the inner nut. To lengthen the cable is the reverse of the above. If the cable is too tight, the idle will be too high, and present other problems.

Tighten both cable nuts securely after the adjustment.

 

Chuck -- you're the man. I was out driving this morning, and noticed the low idle at a stoplight. Sure enough, the A/C button was off (even though the climate control "auto" button was on). I pressed the A/C button and the idle jumped back up from around 450 to 650. I don't know why I never noticed that before. I just assumed that if the "auto" button was on that the a/c was always on as well. I guess when the humidity outside goes down, the a/c automatically shuts off. Anyway, problem solved.

e-man

 

glad to hear it e

 

LOL, yes i did sell my gs but i will NEVER forget all the people that helped me here on CL. This by far REMAINS the best Car Forum Board out here. The MB forum board is also helpful but still not the same. Besides, i will be getting another lexus eventually

 

Keep in mind the ac compressor will shut off automatically when the temp gets to 32 or below, even if it was on before in auto. When the temp warms up I think it will start up again on its own but not sure.

Anyway keep in mind that in cold temps the compressor is disabled. At least this is how my 01 and now 03 is.

 

So how does the S-class compare to the GS? I guess that's really not a fair question because the cars are in two different classes. How about this -- how does Mercedes compare to Lexus?

 

My father has an 01 S Class, I have a 98 GS. I absolutely hate his car, and so does he - so many issues. Sorry to revive this thread, but there is NO comparison.

btw, LS all the way...