Runs horrible with A/C on

Reply Subscribe

Thread Tools

Search this Thread

Feb 16, 2016 | 08:22 PM

FormulasOnly

Thread Starter

Member

Joined: Apr 2014

Posts: 194

Likes: 2

From: Los Angeles

Car: 1989 Formula 350

Engine: 350

Transmission: T-5

Axle/Gears: 3:23

Runs horrible with A/C on

1989 Formula 350 TPI This came on all of a sudden. If I turn on the A/C it will barely run... At forst I thought the compressor was seizing up but I don't hear any of the tell tale noises from the compressor.
Is there something that turns on that isnt?

Feb 16, 2016 | 08:27 PM

eseibel67

Supreme Member

Joined: Jul 2009

Posts: 2,328

Likes: 10

From: Kitchener, ON

Car: 1988 GTA

Engine: LB9

Transmission: T5

Axle/Gears: 3.45

Re: Runs horrible with A/C on

When you shift from park to drive, does the engine RPM lower slightly? If yes, suspect your idle motor might be the problem.

Feb 16, 2016 | 08:44 PM

FormulasOnly

Thread Starter

Member

Joined: Apr 2014

Posts: 194

Likes: 2

From: Los Angeles

Car: 1989 Formula 350

Engine: 350

Transmission: T-5

Axle/Gears: 3:23

Re: Runs horrible with A/C on

It runs and drives flawlessly other than the A/C. If I turn on the A/C at speed 1500rpm +, it starts bucking and lurching...
The more I think about it... It's probably the compressor.

Feb 16, 2016 | 08:45 PM

FormulasOnly

Thread Starter

Member

Joined: Apr 2014

Posts: 194

Likes: 2

From: Los Angeles

Car: 1989 Formula 350

Engine: 350

Transmission: T-5

Axle/Gears: 3:23

Re: Runs horrible with A/C on

I datalogged it and I can't find anything .... at idle or higher ...

Feb 17, 2016 | 02:42 PM

mrestrictrplate

Member

iTrader: (2)

Joined: Nov 2013

Posts: 297

Likes: 0

From: Freehold NJ

Car: 87 Iroc 5.7,67 SS Camaro,90 Formula

Engine: 355 AFR Superram LPE 219

Transmission: 700r4 3000 stall 4spd 5 spd

Axle/Gears: 3.27

Re: Runs horrible with A/C on

I've had a few cars that run rough stopped at a light with the ac on. I'm listening to this thread for the culprit.

Feb 17, 2016 | 05:48 PM

FormulasOnly

Thread Starter

Member

Joined: Apr 2014

Posts: 194

Likes: 2

From: Los Angeles

Car: 1989 Formula 350

Engine: 350

Transmission: T-5

Axle/Gears: 3:23

Re: Runs horrible with A/C on

Just did a thorough inspection of the belt. It's got about 3,000 miles on it and its fried cracked and looks like its got 103,000 miles on it... I'm 99.9% sure the compressor is starting to lock up or at least dragging hard.