Vacuum at idle and during deceleration acceptable kpa?
#1
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Vacuum at idle and during deceleration acceptable kpa?
My NB2 idles at 37-38kpa @ 900rpm (14.5 AFR, 17 degrees timing) and during hard deceleration pulls a vacuum of 21kpa.
Do these numbers look a little on the high side? I'm thinking the idle vacuum should be more like 29-32kpa and the decel vacuum more like 12-15kpa.
Do these numbers look a little on the high side? I'm thinking the idle vacuum should be more like 29-32kpa and the decel vacuum more like 12-15kpa.
#4
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Suspecting a vacuum leak I re-torqued the upper intake manifold & throttle body bolts. Tightened up the boost hose to throttle body inlet. RTV'd my EGR blanking plates (threw away the old gaskets). Checked the vacuum lines to EFR recirc valve and to ECU.
Now idling at 34kpa and decel is 17kpa. Good enough?
Now idling at 34kpa and decel is 17kpa. Good enough?
#8
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Guess I'd better finish my forged motor build.
#9
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Thanks Ted. If you're suggesting the engine is worn/wearing out that wouldn't be unreasonable. It's a 110k mile totally stock motor that's been abused by an EFR most of this year. Still has 185psi compression across the four cylinders though.
Guess I'd better finish my forged motor build.
Guess I'd better finish my forged motor build.
But yes, a less than healthy motor qualifies as well.
Last edited by Ted75zcar; 09-27-2021 at 07:46 PM.
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