Vaccum importance?
08-31-2006, 03:28 PM
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Vaccum importance?
OK guys... got another question for you about this car... It has some cracking vaccum hoses. The car runs great and sounds great but I know it has got to have some kind of leak because of the cracks. How much do small leaks effect the performance of the vehicle? I know on older cars that relied on the vaccum system for things like wiper advance, fuel pump etc. it was VERY important. Is this so on a '83 S?
08-31-2006, 04:12 PM
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Originally Posted by GeaBaldyVx
OK guys... got another question for you about this car... It has some cracking vaccum hoses. The car runs great and sounds great but I know it has got to have some kind of leak because of the cracks. How much do small leaks effect the performance of the vehicle? I know on older cars that relied on the vaccum system for things like wiper advance, fuel pump etc. it was VERY important. Is this so on a '83 S?
No vacuum = little or no go! I would get all the vac lines changed out asap.
08-31-2006, 04:17 PM
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Originally Posted by BrianG
Vacuum leaks also introduce un-metered air into the air/fuel mixture. Lean-condition operation can result in detonation and rapid engine damage.
Either way, fix the leaks - all new hoses.
08-31-2006, 10:34 PM
#7
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If as stated the car is running great, even at idle, then the vacuum leaks must be very minor if they exist at all. Exterior cracks in the vacuum lines don't always mean leaks but it is a clear indication that the vacuum lines should be changed ASAP (as notes above).
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08-31-2006, 10:40 PM
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Originally Posted by Hacker-Pschorr
Man you guys are super paranoid. Not ideal, he is not going to lean out the motor enough to dentonate the engine! If there is that much of a leak, the fuel pressure regulators are wide open in full rich mode anyway at all RPM's so it's a non issue. I was driving around with a massive manifold leak (a lot more than any vacuum line would cause) still wasn't lean enough to dentontate (per the air / fuel gauge). As for the timing advance - once you are at WOT vacuum has no effect on this anyway & the factory advance settings are very conservative. So even if these leaks are causing his engine to advance a bit sooner than "normal" it's not going to grenade the motor.
Either way, fix the leaks - all new hoses.
Either way, fix the leaks - all new hoses.
08-31-2006, 10:43 PM
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My 79 doesn't have an O2 sensor 
Still, a few vacuum lines leaking isn't going to grenade a motor.
Still, a few vacuum lines leaking isn't going to grenade a motor.
08-31-2006, 10:45 PM
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Originally Posted by Hacker-Pschorr
Still, a few vacuum lines leaking isn't going to grenade a motor.
09-01-2006, 01:05 AM
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Originally Posted by FlyingDog
Some people's motors ping on 93 octane... vacuum leaks aren't going to help that situation.
09-01-2006, 01:06 AM
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Originally Posted by Hacker-Pschorr
If a stock 16V 928 is pinging on 93 octane, then the owner of that car has some issues to work out well beyond vacuum leaks.
09-01-2006, 01:16 AM
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Are we talking about the car on this forum running like 50 degrees advance who's owner claims it's not pinging?
