vacuum line on 1990

Reply Subscribe

Thread Tools

Search this Thread

May 13, 2012 | 06:21 AM

1990 Rudy

Thread Starter

Advanced

Joined: Jul 2009

Posts: 55

Likes: 0

From: beverly hills Michigan

vacuum line on 1990

I have found this vacuum line just hanging there so I plugged it and now i am trying to find where the other end goes ? Photo is taken from the passenger side. This little port is right next to the MAP SENSOR.

Being the Cruise does not work and the AC vents do work properly it

would be nice to figure where it goes ?

I t seems I can not add a photo? am I missing something ?

Thanks,

May 13, 2012 | 10:50 AM

VetteMed

Le Mans Master

Joined: Aug 2005

Posts: 7,392

Likes: 218

From: Merritt Island, FL

connects to a check valve which then leads to vacuum line that supplies vacuum to cruise and HVAC system.

May 13, 2012 | 01:50 PM

1990 Rudy

Thread Starter

Advanced

Joined: Jul 2009

Posts: 55

Likes: 0

From: beverly hills Michigan

Any idea of where that check valve is ?

May 14, 2012 | 03:11 AM

Cliff Harris

Race Director

Joined: Apr 2002

Posts: 10,036

Likes: 346

From: Anaheim CA

The vacuum check valve is next to the distributor on the driver's side. One side goes to the HVAC system in the cabin and the other goes to the cruise control. This is what you're looking for:

May 14, 2012 | 07:32 AM

1990 Rudy

Thread Starter

Advanced

Joined: Jul 2009

Posts: 55

Likes: 0

From: beverly hills Michigan

Cliff, thank you so much for the photo. But I do not see any thing like that. I will have to keep digging.

May 14, 2012 | 09:35 AM

Keystring

Drifting

Joined: Aug 2006

Posts: 1,624

Likes: 2

From: Canandaigua New York

If there is a vacuum line running behind the distributor,or if there is no line, and the check valve is not there, then someone removed it.

Auto Zone should have one.

May 15, 2012 | 03:41 AM

Cliff Harris

Race Director

Joined: Apr 2002

Posts: 10,036

Likes: 346

From: Anaheim CA

The vacuum line that goes to the check valve comes from the rear vacuum port on the plenum (passenger side).

It's just to the left of the fuel pressure gauge in this picture. You can see that it goes around in front of the distributor (refer to the previous picture):

May 15, 2012 | 04:30 AM

rodj

Le Mans Master

Joined: Aug 2000

Posts: 8,838

Likes: 31

From: Australia

Quote:

Originally Posted by 1990 Rudy

Being the Cruise does not work and the AC vents do work properly it

That means someone has most likely removed the valve and connected the HVAC line
from the firewall direct to the vac port on the plenum
Do your vent positions change when you accelerate?