Delasangre4231 Posted October 22, 2009 Share Posted October 22, 2009 So if I turn the key to on but dont start the car I hear this loud pump like noise coming from the front passenger corner of the car, and a hissing sound coming from the top of the engine. I have no idea what it could be. Quote Link to comment Share on other sites More sharing options...
xenonxiii Posted October 22, 2009 Share Posted October 22, 2009 The first sound will likely be the electric vacuum pump used on the Turbos. The Hissing can be anything from a Vacuum leak to a fuel leak. I'd check all vacuum lines Quote Link to comment Share on other sites More sharing options...
Delasangre4231 Posted October 22, 2009 Author Share Posted October 22, 2009 So this electric vacuum pump would stay on forever? Quote Link to comment Share on other sites More sharing options...
xenonxiii Posted October 22, 2009 Share Posted October 22, 2009 So this electric vacuum pump would stay on forever? If there is a Vacuum leak it could in Theory Quote Link to comment Share on other sites More sharing options...
Careless Posted October 26, 2009 Share Posted October 26, 2009 had that problem too. it's the vacuum pump at the front, near the power steering pump. http://www.thumper300zx.com/z31/vacuum/new_vacuum_tank.jpg once you replace the lines with new ones (and you should!) your cruise and heat will work well, and your car will no longer have vacuum leaks. the hissing could be an injector that's stuck open, or the vacuum pump is asking for air all the time. Mine would always make that sound... fix it, and after it's operating fine for a drive or two it won't turn on for mroe than a couple of seconds. now it doesnt make that sound anymore because the diaphragm is probably being pulled by vacuum well now. my heat works too. Quote Link to comment Share on other sites More sharing options...
Delasangre4231 Posted October 26, 2009 Author Share Posted October 26, 2009 I think someone disconnected the hoses to the firewall for the heater core... Is there some reason they would have? Quote Link to comment Share on other sites More sharing options...
Careless Posted October 26, 2009 Share Posted October 26, 2009 sorry, just to correct my previous post. the relay box is located near the power steering pump... the vacuum/air pump you have is near the front of the car, behind the passenger foglight. it's held on by two 12mm bolts. if it's turning on, chances are the diaphragm is good, and when u take the cover off it will still be shiney. as for the your heater being bypassed. it's because you have to remove the entire dash to replace your leaky heater core, which the previous owner didn't wanna do. Quote Link to comment Share on other sites More sharing options...
Delasangre4231 Posted October 26, 2009 Author Share Posted October 26, 2009 Whats the chance the hoses just broke? Quote Link to comment Share on other sites More sharing options...
Careless Posted October 27, 2009 Share Posted October 27, 2009 Whats the chance the hoses just broke? You'll have to take that "chance" to find out. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.