gv78280

in my 78 280 if u look at the fusible links and battery from the driver side just to the left of the links/relay box are two cylinder type objects. one has a vac line to the egr, another has a line to the intake manifold, plus two more vac lines that my manuels don't address.

when pressure is applied to the manifold line, one of the cylinders pushes air out the bottom, a broken diaphram. my question is what is their purpose and does any one know how the lines are supposed to be hooked up???

thanks

stev240z

can you take a pic?

-Steve
http://hometown.aol.com/stev240z

toecutter

last nite i had a strange hissing noise that sounded like a vacuum leak coming from that area of the engine. In the morning i found it to be a T section of piping had broken leaving one of the small lines disconnected. I think it ran to the brake booster. It was annoying as hell last nite though when things were'nt so visible. This may be what your talking about but hard to say because my car is RHD, and i'm not sure if they sit on the same side in a LHD zed.

gv78280

sometimes i type before i think. the lines connect to the hook/plunger thing by the throttle linkage, and to the intake manifold, plus two or three more lines. i think the cylinders both get fed mainfold vac and then control two different things, not sure what though

Snapper

The cylindrical objects that you refer to are "magnet valves" which control vacuum to your heater/air conditioner system and the fast idle device which increases engine rpm when the air conditioner is operating. You should make sure that all of the vacuum lines to these devices are connected and intact, or your heater/air conditioner won't work properly.

gv78280

snapper, the problem is my car runs till it gets warm and then randomly dies over the course of like 30 seconds, starts right back up and will eventually die. it sounds similar to lifting the egr diaphram at idle. im thinking the TVV, the thermal valve that allows vac to the egr. one cylinder is connected to the intake and when u blow in it the air into the line at the intake air comes out the bottom of the cylinder. is this an intake vac leak?????

thanks again

Snapper

My guess is that your killing/starting problems are due to a vacuum leak--most likely through one of the magnet valves. Try plugging the one that seems to leak off of the system and see what happens. You can probably get a replacement through a Z junkyard searcher. I know one in the northern California area if you need a source.

AllmyZs

Do you have cruise control. I only ask cause my 79 and 81 have those exact cylinders and lines and they go to the cruise control.

Gotta get my Z's