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Discussion Starter · #1 ·
I just replaced my old DISA valve with a new one ($200+). The old one was not falling apart like some people's do. It just did not close. The actuator link did not pull into the vacuum assembly. I was getting lots of P0171, P0i74 and misfire codes. Also rough idle and lower than normal in-town gas mileage.

I put the new one in. Very clean and easy install. Tightened it up evenly and it fits securely to the intake manifold. Started the engine and the valve DOES NOT CLOSE! There's no movement at all of the actuator link. Moved it by hand to make sure it is not stuck. Checked the voltage at the connector from the ECM - it's 13.5 volts. Checked the resistance of the solenoid coil in the new DISA. It's 45 ohms, same as on the old one.

It still it does not actuate. I know I may have other problems besides the DISA, but the fact remains that neither valve, the old one or the new one, will close in spite of the fact that it's mounted properly, there's 13.5 volts to it and its solenoid coil is good.

What am I missing??
 

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Discussion Starter · #2 ·
Follow up to "brand new DISA" post

Since my original post yesterday, Ive done the following:
* Cleaned MAF sensor with aerosol electronic contact cleaner
* Replaced rear pre-cat O2 sensor (Bank 2, Sensor 1) with a Bosch 13477 heated sensor
* I cleared the engine light and it came back on after a short drive. The problem code is the P0171, with assorted misfire codes thrown in for good measure (P0300, P1343, and P1347). I have attached screen prints from my latest test with my AutoEnginuity scanner. If anyone can get a clue what is wrong from my live data screen, I'd be very grateful
* I also used this clever method [link below] to try to test for intake vacuum leaks. It supposedly tests your intake using a shop vac WITHOUT YOUR ENGINE RUNNING. When I applied the vacuum all I could hear was a gurgling sound in the intake manifold. I then taped up my exhaust pipes in case one cylinder had its intake and exhaust valves open at the same time. I pulled the vacuum for about 3 minutes and the gurgling continued without decreasing. Finally gave up and ordered another O2 sensor with overnight delivery.
http://www.bimmerboard.com/forums/posts/559025
 

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Have you applied voltage to the valve itself?

Edit: Or more importantly have you used DIS or INPA to try and activate or disable the valve?
 

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AutoEnginuity should also be able to activate the DISA valve.
With fuel trims of >+20% you have a large vacuum leak OR a fuel pressure / volume issue, have you checked the vacuum line to the DISA valve and the canister it runs to? ( it may be the same vacuum source used for the exhaust flap)
Another common source for vacuum leaks is the line that runs behind the valve cover to the secondary air pump. (especually if the valve cover gasket has been replaced recently)

With the long term fuel trims at 0, it isn't likely to be a fuel pressure/volume issue.

Is your engine the M54 or the M56 325?
 

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Same symptoms here. Voltage at the connector to the DME, ~47 ohms across the pins on the DISA valve, plenty of smooth resistance when I move the flap by hand, it defaults to the open position, and I can hear clicking when I try to activate the valve itself. But... the arm only moves a little bit. Should there be something hooked up to the vacuum port on the bottom? If so, pics please... I can't find any missing vacuum hoses and I don't recall disconnecting anything.
 

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New disa

My new disa did not activate. I checked the current off the socket I had over 12v then checked the ground with a ohm meter and there was no ground! Has anyone had this problem. I added a new lead for the ground and now it works. But still having codes pop up p0172 p0174 p1084 p1085 and a weak signal code for the disa code. a slight back fire to is still there.
 

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Vacuum line to the DISA valve??
I second that, vacuum line to the DISA valve???
There are none.

There is no vaccum lines going to the DISA .

OP, disa will NEVER cause the type of problems you're describing. NEVER. It wont cause misfires, it wont cause bad fuel mileage , none of those things.


P0171, P0i74 are simple lean codes. They mean you have an air leak somewhere. You got a new disa, so the leak between the disa and mani is now eliminated. Check your intake boots, ESPECIALLY the lower one. Take it out and actually inspect it.

Misfires can be caused by a faulty coil or a big air leak.

Forget about the disa it has nothing to do with all this.

I wild guess on why your new disa wont close may be due to the fact that you have such a big air leak that the diaphragm cant pressurize off of the intake mani. :hmm:
 

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Hello BorderMancer,
Found your thread and am curious how you resolved your unresponsive DISA issue. I am having the same problem.
DISA responds to any 12V power source except the 12V from the DISA circuit.
Thanks!
 

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Hello BorderMancer,
Found your thread and am curious how you resolved your unresponsive DISA issue. I am having the same problem.
DISA responds to any 12V power source except the 12V from the DISA circuit.
Thanks!
BorderMancer only has 8 posts on this forum and the last post made was slightly over 3 years ago.

I am not sure you will hear back from this member.
 
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