jkermitriley

Hi everyone, I am getting a 2000 mustang at the end of the month. The car shudders when I am at a stop, mainly noticable when the air conditioner is running, if we throw it on vent, it goes away. Any idea?

jkermitriley

It also does what I have noticed other mustangs do, it will try to pull foward even when stopped, as thought he gears are still going, but you have the break down and no gas. Normally happens when it is cold.

LilRoush

I'd say something is up with the AC, and it's not spinnning free enough... causing the motor to stumble on itself due to belt resistance.

jkermitriley

The belts were just replaced and it was doing this before the belts were replaced. Thank you for helping. Nice roush too.

jkermitriley

Bump! Anyone out there able to help with this?

MOOK3456

When the ac is on is it as cold as it should be? Does it blow as hard as it should? What you describe+ these other things ^^ are signs of a bad compressor. If it is, you should replace it before it seizes and melts your new belt.

jkermitriley

Thank you, that sounds like a great start.

jkermitriley

He says that the car runs pretty damn cold when its running. Could it still be the compressor even if it is running "weak". The alternator was replaced 4k miles ago.

MOOK3456

Still could be... Usually what happens is when it starts to go it starts seizing up, sometimes intermittently and your belt has to slide over a non moving pulley which is why you get the shuddering as the belt gets slowed down a bit from the friction...How long has the new belt been on? If it wasn't "just" replaced like a week ago, check it for wear on the underside...Hell even if it was, take a look at it.

I believe places like autozone, etc..can test your compressor for you fairly cheaply.

Edit: pop the hood and start her up with the ac on high. If it's doing that you'll be able to see it if you watch close...Mark the pulley with some whiteout/nail polish or something (that will scratch off easily) if you need to.

jkermitriley

http://www.justanswer.com/questions/...t-a-stop-or-in

What do you think of this answer, this is what is happening to me as well, it shudders to the point where you think it will stall, but then doesn't. If I kick the AC over to vent, the shuddering goes away.