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View Full Version : 1991 Volvo 740 vacuum problem


superkid778
Oct 19, 2005, 02:48 PM
I have a 1991 Volvo 740 2.3 non-turbo that is missing a major vacuum line. It starts the intake manifold and then runs up towards the master cylinder on the firewall. From that point, it "T's" off, with the bottom part of the line going up under the firewall. What I am missing is the other part of the "T". I inherited the car from my in-laws and my father in law thought he could fix it up, but I think he is the culprit for the missing vacuum hose. The car is extremely hard to start and dies if you give it any gas once it is cranked. Any help would be much appreciated. I can provide a picture of the "T" if needed.
Thank you!
Chris

superkid778
Oct 31, 2005, 08:45 PM
Here is a pic of the vacuum line

Neos
Apr 23, 2007, 12:29 PM
I saw that in the junkyard the other day. I have a 760 turbo so my setup is different.
It definitely won't run with that hose missing. There is an idle control valve below the intake manifold - usually round, silver, about 6" long. It should have two hoses coming from it. If one is missing - that is probably the hose you are looking for.

Note. Onlooking back at the picture - my answer above may not be right, as I can't picture a hose going all the way from the firewall there to under the manifold. You can always post that pix on the Brickboard.. The Volvo Resource: brickboard.com (http://www.brickboard.com) after you set up an account. Someone will know for sure.

Note on the note. I just noted when you posted this, Hope by now you have found the answer.

juliocg
Jan 10, 2012, 03:57 PM
Buen dia seÑores
Tengo un volvo 740 turbo 1991 que al poner en marcha el motor y acelerarlo a 1000 rpm corta el pulso de injeccion y no acelera quiza alguien me pueda a ayudar

MOORERM
Sep 10, 2012, 07:00 AM
A hose that size looks like it should go to the brake assist vacuum box

MOORERM
Sep 10, 2012, 07:00 AM
Looks like it should go to the brake vacuum assist box