DIY: How to CORRECTLY open your DISA valve for rebuilding

[desertman123]

Do you suffer from a weak or even floppy shaft? Is your performance... lacking? Well gentlemen, it is 2018 and we have solutions to this problem. No need to buy expensive supplements, because we can make work what we were already blessed with!

I've seen too many people hack up their DISA valve trying to take them apart for rebuilding. This gets plastic bits everywhere, and makes it a pain to glue the unit back together, on top of risking cutting into the motor/circuit board. Here's the EASY way to perfectly disassemble the unit. No need to spend $$$ on a brand new DISA.

What you'll need for this job is:
• multiple 1 sided razor blades, must be somewhat rigid. Box cutter blades work well
• hammer/mallet
• (not necessary but recommend) vice to hold DISA
• patience
• protection, we will be hitting a razor blade with a hammer


If you look closely you can see that the DISA is actually multiple pieces, bonded together from the factory. We will be cutting along this line.


Find a corner where you can clearly see the pieces separate. Place your razor blade along this line and start tapping. Don't be afraid to give it a decent tap, but don't brute force it. The razor WILL start sinking into the seam. Tap until you feel the razor is decently into the valve. You can see in the picture about how deep you want to go.



Now just slowly and meticulously follow the seam, tapping the razor blade in. Be careful, but you'll quickly get an idea of how much pressure you should apply. It's easiest to pop open each corner, then move towards the flat parts of the seam. Don't try to cut too much of the seam at once, don't wanna crack the plastic or break the razor. You can see a broken blade on the left




That's it! Now continue with your DISA rebuild.

[drunkenup]

I have a code for my big DISA and with 100k its probably overdue for the rebuild. Which kit are you using for the rebuild?

Did you notice any driveability issues? My engine gets all jerky when I lift or tip in the throttle. I also suspect the DISA got stuck on a very cold day when the jerkiness went away and the intake noise was amplified

[desertman123]

Originally Posted by drunkenup

I have a code for my big DISA and with 100k its probably overdue for the rebuild. Which kit are you using for the rebuild?

Did you notice any driveability issues? My engine gets all jerky when I lift or tip in the throttle. I also suspect the DISA got stuck on a very cold day when the jerkiness went away and the intake noise was amplified

There's a kit for both the large and small DISA on ebay, I just ordered that.

Haven't installed the manifold yet - I imagine the X3 that this came off of wasn't running to well considering all the oil in the intake and this flap is sheared.

[chris_flies]

This'll come in handy when my newfound DISA's inevitably give in.
You're a star of humor...

[drunkenup]

Thoughts on what you're using to glue the cap back to the rest of the disa?

[desertman123]

Originally Posted by drunkenup

Thoughts on what you're using to glue the cap back to the rest of the disa?

I used black JB weld. High temp, oil resistant and says it bonds to plastic.

A few months later I have not had any issues.

[chris_flies]

Here's my new problem:

https://photos.app.goo.gl/PrgWs7Ap5gjU8YJC2

I assume that this means it's rebuild time

What rebuild kit did you use, good sire?

EDIT: It's the Upper DISA, above the TB, the one that's easily accessed...

[desertman123]

Originally Posted by chris_flies

Here's my new problem:

https://photos.app.goo.gl/PrgWs7Ap5gjU8YJC2

I assume that this means it's rebuild time

What rebuild kit did you use, good sire?

EDIT: It's the Upper DISA, above the TB, the one that's easily accessed...

https://www.ebay.com/itm/Aluminium-R...ss!32174!US!-1

Same kit as VANOS-BMW.com but it won't take a month and a half to come from Moscow. You could probably just go pay the guy a visit to skip shipping lmao.

I wanna pull my valve and double check one of these days but everything been running great lately.

And I can confirm that as of today, in June, my DISA is still JB welded together without issue.

[chris_flies]

Ordered the kit (finally), we'll see how this works out.

And yes, my performance is lacking. There isn't anything left after 5k...

[desertman123]

Originally Posted by drunkenup

I have a code for my big DISA and with 100k its probably overdue for the rebuild. Which kit are you using for the rebuild?

Did you notice any driveability issues? My engine gets all jerky when I lift or tip in the throttle. I also suspect the DISA got stuck on a very cold day when the jerkiness went away and the intake noise was amplified

Lol now that you mention it yes my car can be very jerky. Got a code for the small disa but it hasn't returned after I cleared it.

Originally Posted by chris_flies

Ordered the kit (finally), we'll see how this works out.

And yes, my performance is lacking. There isn't anything left after 5k...

Honestly it's got me thinking about the N54 intake manifold.. no DISAs to fail.

[drunkenup]

Originally Posted by desertman123

Lol now that you mention it yes my car can be very jerky. Got a code for the small disa but it hasn't returned after I cleared it.

Honestly it's got me thinking about the N54 intake manifold.. no DISAs to fail.

Since the rebuild the really worst of the lift-off jerk disappeared, but throttle tip-in and lift still causes a minor jerk. Occasionally it jerks more violently. Thought it might be bad motor mounts, vacuum leak (maybe the breather hose), but my doubts are growing on the DISA.

[desertman123]

Originally Posted by drunkenup

Since the rebuild the really worst of the lift-off jerk disappeared, but throttle tip-in and lift still causes a minor jerk. Occasionally it jerks more violently. Thought it might be bad motor mounts, vacuum leak (maybe the breather hose), but my doubts are growing on the DISA.

I have a brand new breather hose and motor mounts within the last ~10k mi. Not sure if we're describing the same exact thing. For me the jerking happens at low speeds, like if I give it a bit too much throttle after the clutch engages it'll CHUG-uh-CHUG-uh unless I immediately pull off.

Do you have a manual trans? I began thinking my jerking was from a DMFW getting quite worn - but with your input it might be that the DISAs failing, or maybe a combination of all the above.

And I've always suspected a vacuum leak. My idle once fully warmed up occasionally feels a little rough/vibrates- the RPMs don't move at all, but it feels like I have the AC on. I don't know exactly how smooth this car is supposed to be, but it would be an explanation for these small symptoms. Fuel mileage is good and so is performance, but who knows.

The motor hisses a little bit - I know these things make all sorts of odd noises but the hissing can be a bit loud. This is what prompted me to replace the breather hose. I tried a real quick at home smoke test but didn't see anything. When I did my valve cover gasket one of the little breather things broke off so I reglued it, maybe that's it? Who knows, I'll check it out when I have time or whenever I do the MILVs.

[drunkenup]

It is a manual and I suspect it could also be the DMFW too, although the car only has 107k on the clock. I do get a shudder just like you described, sort of like wheel hop?

Before I rebuilt it the second time, the car would go into what I suppose is MAF-less mode and froze the DISA's if I drove it on a long-enough trip. It would drink fuel, fluctuate idle, and feel down on power but it would run so smooth. That's my anecdote for why I think the DISA is still acting up.

[chris_flies]

I get that same wheel hop feel, it isn't actually wheel hop, since it didn't do it when I launched the car (for the first time). I think it's a combination of various soft bushings involving the drivetrain, and just having the wrong throttle input at the wrong speed with the wrong clutch input probably exacerbated by the DMFW.

[Suhb]

I get judder in second gear around 1-1.5k rpm. Only for a brief moment and then it goes away when the RPM's rise. Car is also jerky and on and off throttle. It's def the DMFW. Damn thing also has the classic DMFW rattle in neutral after driving for a bit.

My car also has a slight rumble at idle. Brand new motors mounts. Changed vanos solenoids. New eccentric shaft sensor. New valve cover and PCV hose. Shop ran a smoke test, no vacuum leaks. Car still has a very slight rumble despite no misfires. Also the RPMs sometimes dips when coming to a stop. A part of me suspects it's also tied to the DMFW.

I've been looking around for a better solution to the stock DMFW but don't want to go single mass and increase the NVH. There needs to be a better middle ground.

[desertman123]

Originally Posted by Suhb

I get judder in second gear around 1-1.5k rpm. Only for a brief moment and then it goes away when the RPM's rise. Car is also jerky and on and off throttle. It's def the DMFW. Damn thing also has the classic DMFW rattle in neutral after driving for a bit.

My car also has a slight rumble at idle. Brand new motors mounts. Changed vanos solenoids. New eccentric shaft sensor. New valve cover and PCV hose. Shop ran a smoke test, no vacuum leaks. Car still has a very slight rumble despite no misfires. Also the RPMs sometimes dips when coming to a stop. A part of me suspects it's also tied to the DMFW.

I've been looking around for a better solution to the stock DMFW but don't want to go single mass and increase the NVH. There needs to be a better middle ground.

I've been really thinking about that Valeo single mass conversion kit - it weighs the same as the original pieces. If we're already getting a bit of rattle from a worn dual-mass, then I don't think a single mass would really be that bad unless you get a lightened flywheel. The clutch is now sprung - I saw some people arguing that you're not solving the problem just moving it. I'd argue you're still solving it to some degree: the flywheel is less of a wear item now, and you moved the damping to the piece you'd always replace.



Also if I had a nickel for every time someone mentioned these cars stumble a bit at idle.. I don't know what's going on but seems like many many people experience this. I figure I still get great performance and gas mileage so it can't be TOO broken.

[chris_flies]

Originally Posted by desertman123

I've been really thinking about that Valeo single mass conversion kit - it weighs the same as the original pieces. If we're already getting a bit of rattle from a worn dual-mass, then I don't think a single mass would really be that bad unless you get a lightened flywheel. The clutch is now sprung - I saw some people arguing that you're not solving the problem just moving it. I'd argue you're still solving it to some degree: the flywheel is less of a wear item now, and you moved the damping to the piece you'd always replace.

Also if I had a nickel for every time someone mentioned these cars stumble a bit at idle.. I don't know what's going on but seems like many many people experience this. I figure I still get great performance and gas mileage so it can't be TOO broken.

I have a solution to the idle problem...don't idle the car, rev the nuts off of it all day long! It can (probably) handle it.

And yeah, that single mass kit would be the one I'll be getting when it's time for it. OEM (not to be confused with OE) quality, plus a good reliability and refinement upgrade...

[chris_flies]

I had a problem with the rebuild kit. I tightened it enough so that it wouldn't prevent it from turning at all, but tight enough so that there wasn't too much play, but the pin ended up backing out and separated the halves of the casing. I was just having a bunch of issues with it.

Much fiddling later, I've put the original flap and pin/gear back in, and it's good. We'll see if it just needed an assembly/disassembly to work out whatever kink there was, if there was ever an issue at all.

Oh well...now I know how to actuate them in INPA

[desertman123]

Originally Posted by chris_flies

I had a problem with the rebuild kit. I tightened it enough so that it wouldn't prevent it from turning at all, but tight enough so that there wasn't too much play, but the pin ended up backing out and separated the halves of the casing. I was just having a bunch of issues with it.

Much fiddling later, I've put the original flap and pin/gear back in, and it's good. We'll see if it just needed an assembly/disassembly to work out whatever kink there was, if there was ever an issue at all.

Oh well...now I know how to actuate them in INPA

That's sorta what happened to me. I think the rebuild kit only works for 1 revision of the DISAs. I just cranked it down and greased it and it worked. The flap ended up being pretty tight, but it actuated fine. If you look at my youtube channel (same name) I have a video of it.

On my friends disa, it actually worked like it should- it was tightened fully but the flap opened and closed very easily. Not like ours where it actually prevented the flap from being resistance free.

As long as it works who cares lol. I was thinking of just biting the bullet and getting brand new DISAs so I have the latest revision, no hacked up rebuild kits and question motor/driver board health (as in where the flap only sorta opens slowly)

And again, considering the N54 IM to avoid these issues. Decisions.

[chris_flies]

Originally Posted by desertman123

That's sorta what happened to me. I think the rebuild kit only works for 1 revision of the DISAs. I just cranked it down and greased it and it worked. The flap ended up being pretty tight, but it actuated fine. If you look at my youtube channel (same name) I have a video of it.

On my friends disa, it actually worked like it should- it was tightened fully but the flap opened and closed very easily. Not like ours where it actually prevented the flap from being resistance free.

As long as it works who cares lol. I was thinking of just biting the bullet and getting brand new DISAs so I have the latest revision, no hacked up rebuild kits and question motor/driver board health (as in where the flap only sorta opens slowly)

And again, considering the N54 IM to avoid these issues. Decisions.

That N54 manifold would make the top end really shine (and dyno's show that it does). The lack of maintenance would be nice, but I like my low-end shove and the cool factor of an intake with variable-length intake runners...

Thanks for the DIY, hopefully I won't actually need it someday...

[juld0zer]

For the juddering, try roasting the clutch a bit. Sort of like re-bedding brakes to clean the surfaces.
Warm up the engine and chock the rear wheels, pull up the handbrake as hard as you can. Select 1st gear, bring the revs to 2200ish and gently ease the clutch until you feel strong propulsion. Moderate the gas pedal to maintain steady revs for about 5 seconds, then rest for 30 seconds and repeat two more times.

Mine has 130k km, CDV punched out and most recently, the hill holder coded off. I thought it was a VANOS issue but it would still occasionally do it with a new set of genuine solenoids and check valves. There was a bloke on an Audi forum who went through several DMF and clutches and the juddering kept coming back. He contacted LuK UK and the technical dept gave him that tip.
Coding off the hill holder greatly helps prevent reoccurrence. I do wonder if the CDV delete led to the judder as it reduces the amount of clutch slip on quick changes. Perhaps the CDV is there also to promote a little slip to keep the flywheel/pressure plate clean?