V3: Step AT Vacuum Fluctuation at low RPM?

ironic · 07-02-2008, 10:10 PM

I just installed my v3 yesterday and reset the ecu, but it's still possible the car needs time to adapt.

Anyways, here's the rundown:

If I'm cruising at about or just under 1200 rpm in 4th (manual mode in step) the car's boost fluctuates up and down about 2psi. It's hardly noticeable but under constant throttle the car does feel like it surges slightly and then backs off. This is just under vacuum, when I actually accelerate this disappears. I haven't had any codes or errors with the v3 - it pulls like a bat out of hell.

Any ideas?

It's v3 PNP with stage 2 map

Sniz · 07-02-2008, 11:26 PM

sounds normal to me......is this the 1st time you've had a boost gauge? My car moves around in vacuum a ton, very small throtte inputs change vacuum constantly it seems. No boost on the other hand should not do that.

ironic · 07-03-2008, 02:53 AM

yeah i had a talk to one of my good friends and a beta tester for some time. he says it's normal as well. the thing is i can feel the car pull a little bit and then settle back down. it's very subtle but noticeable. that's what got me looking at my boost gauge and seeing it fluctuate in the first place

07-02-2008, 10:10 PM	#1
ironic Major General 271 Rep 8,338 Posts Drives: Jet Black 335i Join Date: Dec 2006 Location: San Francisco, Ca iTrader: (22)	V3: Step AT Vacuum Fluctuation at low RPM? I just installed my v3 yesterday and reset the ecu, but it's still possible the car needs time to adapt. Anyways, here's the rundown: If I'm cruising at about or just under 1200 rpm in 4th (manual mode in step) the car's boost fluctuates up and down about 2psi. It's hardly noticeable but under constant throttle the car does feel like it surges slightly and then backs off. This is just under vacuum, when I actually accelerate this disappears. I haven't had any codes or errors with the v3 - it pulls like a bat out of hell. Any ideas? It's v3 PNP with stage 2 map __________________ Widebody 335i Project Car BUILD \| PHOTOSHOOT
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07-02-2008, 11:26 PM	#2
Sniz Lieutenant General 715 Rep 10,584 Posts Drives: e92 335 - gone // e36 M3 turbo Join Date: Mar 2007 Location: Ellicott City, MD iTrader: (1)	sounds normal to me......is this the 1st time you've had a boost gauge? My car moves around in vacuum a ton, very small throtte inputs change vacuum constantly it seems. No boost on the other hand should not do that. __________________
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07-03-2008, 02:53 AM	#3
ironic Major General 271 Rep 8,338 Posts Drives: Jet Black 335i Join Date: Dec 2006 Location: San Francisco, Ca iTrader: (22)	yeah i had a talk to one of my good friends and a beta tester for some time. he says it's normal as well. the thing is i can feel the car pull a little bit and then settle back down. it's very subtle but noticeable. that's what got me looking at my boost gauge and seeing it fluctuate in the first place __________________ Widebody 335i Project Car BUILD \| PHOTOSHOOT
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