German Auto Solutions (GSA) DISA rebuild kit=legit.

Just got done with this preventative(well, I say preventative because it hadn't totally failed but it was knocking...more on this later), DISA rebuild kit from GAS.

First thoughts: I opened the small fed ex package and noticed the thoroughness of the kit. It includes things such as bailing wire to hold things, q-tips to add loc-tite and grease, and even the loc-tite and grease. I have never had a rebuild kit come so well equipped.

I had inspected my DISA prior when it first started knocking, and didn't find much wrong with it to the feel/eye. However, this time when I pulled it apart the pin(the infamous engine destroyer one) was already partially loose. In other words, I literally just pulled it out easily with a pair of pliers-scary. In all fairness, I had been slacking on this as it has been making some noise for about 10k miles(3-4 months). I really need to start realizing that I drive the crap out of this thing and that time is irrelevant.

So, After I had it out I open up the laptop and actually follow the instructions(as a guy, this is hard to admit...). I discovered something, these instructions are 100%(not 99%, not almost but not quite), accurate. Instructions for a rebuild kit that actually work? HOLY ****!

The rebuild went without drama, and when re-installed the engine is quiet again, no CEL, no more vacuum leaks on cold starts thanks to the new O-ring.

This is a very easy and enjoyable way to spend just about an hour of your time, and I highly recommend this be done. I also like the way the rebuild kit has no possible way of letting anything go into the engine. It seems like a much better design than the original. I know hard core BMW people will say otherwise, but I am willing to bet that GAS has way more R&D, and most importantly field experience into this one particular component than BMW did upon creating it.

Just thought I'd share, if you are being lazy on this cut it out and do it.

http://forum.e46fanatics.com/showthread.php?t=964380

Nice review, but cars are built to a budget. If that level of "thoroughness" was applied to every single part, the E46 would have easily been twice, three, or four times as much. It's not about R&D, it's about being a business, and you can't do that without profit.

FWIW, the original DISA is still great on my car (knock on wood) and has been in service for 200-300k miles for some other members. Replacing it once during the car's lifetime will probably suffice.

Originally Posted by Mango

Nice review, but cars are built to a budget. If that level of "thoroughness" was applied to every single part, the E46 would have easily been twice, three, or four times as much. It's not about R&D, it's about being a business, and you can't do that without profit.

FWIW, the original DISA is still great on my car (knock on wood) and has been in service for 200-300k miles for some other members. Replacing it once during the car's lifetime will probably suffice.

100% agree with you Mango. I'm shocked to hear you haven't replaced it yet though. Mine was still OK up until about 135k FWIW.

As far as that link, didn't think to search for it but who cares really. More people endorsing a product isn't a bad thing, just giving my experience. Now, if I ever ask what kind of oil to use, I will send myself into the flames!

edit: With this pin that can fall out, is it not pressed up against the other wall of the intake manifold? I was thinking about this, it seems it would have to be in order for DISA to have any real effect on air flow....If that is the case, how is it able to fall out on some vehicles?

The GAS solution seems like a good one. That said, this wasn't available when the DISA on my coupe developed a sizable play between the rotating lever and the flap 4 years ago with about 50k miles. I had a choice to buy or rebuild. Rebuilding was free, so I started with that.

Took everything apart and scrubbed it with brake cleaner, inside out. I filled the cavity where the lever and pin goes into the flap (both ends) with epoxy, lightly scoring all the mating surfaces, and put everything back together. I greased the lever and rod interface with grease and put it back in the car. I recently took it apart recently to inspect it and at 101k miles the lever and flap have developed no play, so looks like the repair has held up good. Pin is likewise still tight.

The GAS solution is a convenient "repair in a box" and does look like a fun activity for any M54/M52 owner, but in my opinion those looking to repair their DISA without the panache of machined aluminum and titanium can go with good ole fashioned epoxy, assuming the gaps aren't too far gone.

Then there's the rubber bladder in the vacuum pot regardless of which rebuild solution you use...

Originally Posted by RG5384

100% agree with you Mango. I'm shocked to hear you haven't replaced it yet though. Mine was still OK up until about 135k FWIW.

As far as that link, didn't think to search for it but who cares really. More people endorsing a product isn't a bad thing, just giving my experience. Now, if I ever ask what kind of oil to use, I will send myself into the flames!

edit: With this pin that can fall out, is it not pressed up against the other wall of the intake manifold? I was thinking about this, it seems it would have to be in order for DISA to have any real effect on air flow....If that is the case, how is it able to fall out on some vehicles?

That's the thing. I don't think it's ever fallen out on some vehicles. I think people have mistaken it for falling out probably because it fell out upon removal by their mechanic and they just didn't detect it.

Originally Posted by cvx5832

The GAS solution seems like a good one. That said, this wasn't available when the DISA on my coupe developed a sizable play between the rotating lever and the flap 4 years ago with about 50k miles. I had a choice to buy or rebuild. Rebuilding was free, so I started with that.

Took everything apart and scrubbed it with brake cleaner, inside out. I filled the cavity where the lever and pin goes into the flap (both ends) with epoxy, lightly scoring all the mating surfaces, and put everything back together. I greased the lever and rod interface with grease and put it back in the car. I recently took it apart recently to inspect it and at 101k miles the lever and flap have developed no play, so looks like the repair has held up good. Pin is likewise still tight.

The GAS solution is a convenient "repair in a box" and does look like a fun activity for any M54/M52 owner, but in my opinion those looking to repair their DISA without the panache of machined aluminum and titanium can go with good ole fashioned epoxy, assuming the gaps aren't too far gone.

Then there's the rubber bladder in the vacuum pot regardless of which rebuild solution you use...

Nice review and pictures. Does the GAS kit prevent the gaps from becoming big? I've never really studied the parts of the DISA

Originally Posted by Mango

Nice review and pictures. Does the GAS kit prevent the gaps from becoming big? I've never really studied the parts of the DISA

The lever on the GAS solution has a square profile, tapered "key" that mates into the flap. That tells me that properly torqued, there should be no gaps to speak of and should be "wedged" in there. The 6061-T6 aluminum material that's used is also the same one used in a lot of AR-15s and is proven to wear very well against abuse and moving parts. I haven't examined one personally, but the design and materials shared on the website lead me to think it's a good (even elegant) answer to the flap failure inevitability (albeit thousands of miles) of the M54/M52 DISA.

That said the bladder on the vacuum pot is a totally different issue and has been documented to fail and cause DISA as well as lean mixture problems.

Courtesy of GAS:

Question on the disa vale rebuild, I have a y2k 323ci that is not listed for the G.A.S. rebuild kit, are these disa's a different type that is not prone to need repair? Just curious.

Originally Posted by 1st bimmer

Question on the disa vale rebuild, I have a y2k 323ci that is not listed for the G.A.S. rebuild kit, are these disa's a different type that is not prone to need repair? Just curious.

I may be wrong, but I don't believe you have one. Not all BMW's have these, it is mainly just a performance item that has the ability to change the intake runner from short to long depending on engine rpm and throttle position.


On another note, I Just confirmed this morning that my cold rough idle is gone now as well. I suspected I had a small intake leak coming from this stupid thing for a while now, but I wasn't going to mess with it until I did the rebuild kit.

Good job on the rebuild kit, althought I would have recommended on just buying a new DISA instead of repairing your current one. The reason why is because sooner or later the diaphragm might fail (that happened to me...butterfly is perfect but diaphragm not holding vacuum) Once that happens you're going to have to buy a new DISA anyways since you can't repair/replace the diaphragm (wish you could) But I guess if you didn't want to spend $250 to $280 right now that's totally understandable. Got lucky and found a new one on ebay for $150. Receiving it this week.

You can always transplant the GAS kit into a new DISA. (As long as you don't put it together with epoxy.)

Originally Posted by RG5384

I may be wrong, but I don't believe you have one. Not all BMW's have these, it is mainly just a performance item that has the ability to change the intake runner from short to long depending on engine rpm and throttle position.

323Ci = M52TU, so it does have a DISA unit. However he is correct in that GAS doesn't make one for it, at least not as of right now when I checked their website.

Originally Posted by wildirish317

You can always transplant the GAS kit into a new DISA. (As long as you don't put it together with epoxy.)

I wanted to, but with the Dorman DISA at $100....I just wanted to get a whole new DISA. I'll transplant a GAS kit into it maybe some other time. I want to get a fluorosilicone o-ring onto it, because that molded o-ring is garbage.

A guy who works on e46 bimmers a lot posted on a german BMW forum not too long ago that DISAs dont just fail mechanically. They also fail electrically (people often dont notice that). So - I wouldnt waste money on fixing my DISA if it failed. Id buy a new one.

Originally Posted by silyb0y

A guy who works on e46 bimmers a lot posted on a german BMW forum not too long ago that DISAs dont just fail mechanically. They also fail electrically (people often dont notice that). So - I wouldnt waste money on fixing my DISA if it failed. Id buy a new one.

So, because a guy posted something on a forum a while back you wouldn't trust a kit that is widely known to fix a common problem?

Of course they could fail electronically, or the diaphragm could fail. Both of those components worked on mine so it made MUCH more sense to spend 1/3 the cost and put it back on the road.

Additionally, one of the main concerns with this part isn't it failing and not working, but it failing and sending parts into the engine. With the GAS kit, there is now way possible for this to happen.

To be perfectly honest, if it fails electronically tomorrow it would be a long time before it would be fixed, it does not throw a CEL, and frankly unless the car is on a track or a dyno you will be hard pressed to tell the difference.

Originally Posted by RG5384

Of course they could fail electronically, or the diaphragm could fail. Both of those components worked on mine so it made MUCH more sense to spend 1/3 the cost and put it back on the road.

To be perfectly honest, if it fails electronically tomorrow it would be a long time before it would be fixed, it does not throw a CEL, and frankly unless the car is on a track or a dyno you will be hard pressed to tell the difference.

Good points (highlighted). I still insist that the GAS kit is a good investment, as it can be transferred to your next DISA, should you need one.