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Discussion Starter #1
I have been working on my non-starting 1987 graduate for a couple of weeks, and since I do not have the cardisk cd yet, I need some help.

I have been looking at the EFI, and will start diagnosing it as per the L-jet diag page by Hi Performance (A BIG HELP.) As I look at the pics, I find that the black cable shown in the pic attached (which by the way comes from the Hi Performance page) that goes from left to right behind the seat belt and disappears as it heads towards the trunk, is loose, unconnected and resting on top of the FI ECU. What is this?
 

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It looks to me like the wires that go to the Manifold Absolute Pressure sensor... at least I think that's what it's called. It should be mounted on the side wall above the cable, and have an air hose running to it as well. Yours might be disconnected or entirely removed. It's not essential to engine performance, but it will make a difference of a couple mpg on your fuel efficiency when running at a steady speed. The MAP sensor is expensive, at least a few hundred dollars. But it will pay for itself in fuel savings over the long run.

Tim
 

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I think the black line you're asking about is part of the vapor recovery system. Item #11 in the sketch below. It should continue on the 'expansion tank' - item #4.

There is a tube that runs from the intake plenum to the manifold pressure sensor (vacuum sensor). That tube (also) runs along the right side, inner sill then it goes up to the sensor located behind the trim panel behind the right side door.
 

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Do you smell gas? That hose (if ghnl is right) takes the gas vapors from the gas tank via the vapor seperator to the charcoal canister behind the right front fender.
 

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Discussion Starter #5 (Edited)
Well, it is not a hose, the end is an electrical (harness) connector as shown in the picture attached. It is very similar (two electrical connectors inside the plug, female end) to the plugs that go to the injectors, except that this one is all black, instead of the off-white color shown here.
 

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I'm pretty sure it goes to the MAP sensor. Here is what the sensor looks like: http://www.international-auto.com/index.cfm?fa=p&pid=2467&posid=851934 Like I said, it isn't cheap. If your sensor is missing, it's not the end of the world. At ten cents a mile, you'll pay for it with around 4k highway miles. Also, if it's missing, it won't be the cause of your "no start" issue.

Tim
 

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Yep, if it has the Bosch connector it must be for the pressure sensor. Remove the 'side lining' - the vertical trim panel behind the right side door. The ignition ECU and vacuum sensor hides in there.
 

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