DISA valve N52 (inner)

beambeam1 · 07-07-2018, 07:04 AM

Quick question: this is the DISA valve I have in my engine at moment but the flap seems very solid, I am not sure if the motor is operating it though.

The rubber membrane that would seal the gap inside it when the flap closes seems to have perished - how much would this affect the efficient operation of this part?

It's just I have ordered a replacement from Quarry Motors on eBay and find that the same membrane is flimsy and peeling away from the plastic casing too. They have offered to refund/replace but is this likely to have a great deal? Should I bite the bullet and pay £225 for the part from BMW?

I feel I already know the answers here but would like if someone could confirm if poor rubber = impairs performance of the part itself. I've searched and searched and all DISA flaws seem to correlate to broken flap or failed motor only.

Thanks - owner of 2006 N52 325i

JuniorB · 07-07-2018, 09:52 AM

The only way to check sensors, (or disa valves) is to power them up. A power probe works great for this, everyone should own one, as some like to just replace parts without knowing if there bad or not. Anyway, you can power up the valve to check movement.

beambeam1 · 07-07-2018, 01:12 PM

I'm not asking about if the flaps move or not but whether the damaged rubber seal internally would impact the performance/efficiency of the part itself.

Power probe sounds a good idea though!

Noir · 07-09-2018, 03:02 PM

I imagine not having a seal might do just that, however so slightly. I would look into some part diagrams (if they go that in depth) on the realoem website. Or let your car have a few days hiatus while you wait for a replacement. That little gasket cant be more than a few bucks.

The Nightman · 07-09-2018, 04:03 PM

Quote:

Originally Posted by beambeam1

I'm not asking about if the flaps move or not but whether the damaged rubber seal internally would impact the performance/efficiency of the part itself.

It has an impact but I don't think anyone can tell you by how much. Unfortunately the gaskets on our DISA valves are not serviceable so I would live with it until the servo motor or flap breaks.

matteblue3er · 07-10-2018, 11:41 AM

You can actuate the valves in ISTA or INPA. Typically the motors are fine, its the flap braking off the motor shaft that is the issue. If the flap is loose, the unit has failed.

As with any gasket failure in the intake system, a vacuum leak can occur, which if large enough, can cause fuel/air mixture issues. This gasket not so much. There really isn't much to it if the gasket does fail. An oring or paper gasket would probably work fine.

07-07-2018, 07:04 AM	#1
beambeam1 Enlisted Member 7 Rep 43 Posts Drives: E91 M Sport 325i Join Date: Jun 2017 Location: Scotland iTrader: (0)	DISA valve N52 (inner) Quick question: this is the DISA valve I have in my engine at moment but the flap seems very solid, I am not sure if the motor is operating it though. The rubber membrane that would seal the gap inside it when the flap closes seems to have perished - how much would this affect the efficient operation of this part? It's just I have ordered a replacement from Quarry Motors on eBay and find that the same membrane is flimsy and peeling away from the plastic casing too. They have offered to refund/replace but is this likely to have a great deal? Should I bite the bullet and pay £225 for the part from BMW? I feel I already know the answers here but would like if someone could confirm if poor rubber = impairs performance of the part itself. I've searched and searched and all DISA flaws seem to correlate to broken flap or failed motor only. Thanks - owner of 2006 N52 325i
	Appreciate 1 Noir883.00 Tweet Quote

07-07-2018, 09:52 AM	#2
JuniorB Major 183 Rep 1,017 Posts Drives: 07 e60 525 N54 Join Date: Mar 2016 Location: Rhode Island iTrader: (0)	The only way to check sensors, (or disa valves) is to power them up. A power probe works great for this, everyone should own one, as some like to just replace parts without knowing if there bad or not. Anyway, you can power up the valve to check movement.
	Appreciate 1 Noir883.00 Quote

07-07-2018, 01:12 PM	#3
beambeam1 Enlisted Member 7 Rep 43 Posts Drives: E91 M Sport 325i Join Date: Jun 2017 Location: Scotland iTrader: (0)	I'm not asking about if the flaps move or not but whether the damaged rubber seal internally would impact the performance/efficiency of the part itself. Power probe sounds a good idea though!
	Appreciate 0 Quote

07-09-2018, 03:02 PM	#4
Noir Major 883 Rep 1,413 Posts Drives: 2006 E90 330i 6MT Join Date: Aug 2016 Location: San Antonio iTrader: (1)	I imagine not having a seal might do just that, however so slightly. I would look into some part diagrams (if they go that in depth) on the realoem website. Or let your car have a few days hiatus while you wait for a replacement. That little gasket cant be more than a few bucks. __________________ See you, space cowboy. *Supercharged*
	Appreciate 0 Quote

07-10-2018, 11:41 AM	#6
matteblue3er Captain 238 Rep 947 Posts Drives: Racecar Join Date: Jul 2015 Location: Philly iTrader: (0)	You can actuate the valves in ISTA or INPA. Typically the motors are fine, its the flap braking off the motor shaft that is the issue. If the flap is loose, the unit has failed. As with any gasket failure in the intake system, a vacuum leak can occur, which if large enough, can cause fuel/air mixture issues. This gasket not so much. There really isn't much to it if the gasket does fail. An oring or paper gasket would probably work fine.
	Appreciate 0 Quote