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Discussion Starter #1
Was checking my timing last night and it seems my vacuum advance does not work (i.e. no change in timing at idle when connected or disconnected).

Seems these aren't available anymore. Does anyone know where I might source one? Or are these fixable?

Or does it even matter? I have read several posts of folks just plugging where the vacuum hose connects at the throttle body.

Thanks!
 

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But Mad North-Northwest
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So there were two setups with the vacuum advance. The earlier V6 cars used plenum vacuum, so there was vacuum on the line to the distributor at idle. The later V6 cars used ported vacuum, so there was no vacuum on the line at idle...you only see vacuum when the throttle plate opens.

On the later cars, disconnecting the vacuum hose at idle doesn't do anything to the advance. If you pull off the hose from the distributor and it's not sucking in air, this is the setup you have.

You can test the later setup with a handheld vacuum pump. This is from memory, but I think it's like 12 degrees advance if you apply 500mbar vacuum to the distributor (the spec is in the service manual).
 

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Discussion Starter #3
That's a good point about sucking air. I'll give that a check.

I've been following the Greg Gordon guide and it mentioned (unless I misread) that whether the old style (retard) of new style (advance) that there should be some timing change when you disconnect & plug at the throttle body vs. having the vacuum advance connected.
 

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But Mad North-Northwest
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Nope. I've done the experiment on my Milano (later advance style) and it makes no difference at idle. I've got a hand pump with gauge and there's no vacuum on the line with the throttle plate closed, so no way for it to change the timing.
 

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Discussion Starter #5
Well that is good news then, as the vacuum advance is unobtanium near as I can tell.
 

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I don't know whether there are similar places in the US that might do it, but I had a company called EFI Spares rebuild my late Alfetta vac advance unit here in Australia when the diaphragm failed 12 months or so ago. Cost me about $120 including freight from memory, better than the answer of NLA that I got from everyone else.
 

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Discussion Starter #7
Yeah - I was thinking of trying to find the same if the need indeed arose. But it looks like I was just testing it wrong, though. So that was an even better outcome. ;-)
 
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