Smoke Tested and I need help

[MIKYZZ4]

Strange, only available from Russia ?
If you can obtain one, let us know how it turns out.

[ilikemycar]

rebuild your disa valve with this https://germanautosolutions.com/prod...sa-repair-kit/

First you should test your disa if it holds vacuum

[ilikemycar]

since you mention you haven’t touched the CCV system i would replace all the components. A bad CCV system can cause all kinds of problems.

[legobumb]

@ilikemycar
I did check the DISA valve to see if it holds a vacuum and it really doesn't. That's why I said it'll need a new membrane. I'm also gonna put a new o-ring in it since the old one is pretty damn flat. It may or may not be the source of the vacuum leak (I doubt it), but it's still important to fix it. I ordered the membrane so hopefully I'll get it within the month (lol from Russia) and I'll be letting everyone here know if it's worth it. I got it for about $25 (this price includes the $10 S&H cost), which is still less than $100-200 for a whole new DISA unit.

What's especially weird is that this evening when I started my car, the CEL didn't come on like usual. I didn't want to believe it so I scanned for codes real quick and they're still there (P0171 and P0174). I kind of scratched my head on that and went into the monitoring part of the app I used and screenshotted the one and only red value. I have NO idea what any of this means. Picture below for reference.

https://imgur.com/a/Moy433D

[Mless5]

I may have a spare DISA for you after my yard run today. I work in Woburn right off i95.

[Critter7r]

Replacing the "oring" on the DISA valve is a 20-minute lesson in retard. It's not an oring, it's manufatured with a bead of silicone in that channel, and you have to scrape it out with a tiny screwdriver in order to put a proper oring on it. That's not the normal failure point of the valve, though. Usually it's the diaphragm or end pin that phaigls.

[Critter7r]

OP, I give it 95% probabitiy that your valve cover is cracked and leaking oil into cyl 1. Wither that, or you installed the spark plug hole gasket wrong.

[legobumb]

Welp. After getting a proper o-ring for the DISA valve and installing it a couple days ago, I cleared my codes yesterday. Shortly after, the CEL came back on with just the P0171 stored and a pending P2096 or whatever. Today, the CEL isn't on at all. I called my car a liar and scanned it and found only the P0171 stored code. No pending codes at all. I think progress has been made! Haha. No more P0174 at least?

[RobertDenali]

Go look up G.A.S e46. They have a rebuild option.

[legobumb]

As I've already mentioned, it's just the membrane on the DISA valve that needs replacing and that's what I ordered. The flap works fine.

[RobertDenali]

The thread was too long too read. Glad you figured it out.

[legobumb]

Still no guarantee that that'll be the source of my vacuum leak, however. I'd like to take a look at my CCV system next. It doesn't seem too complicated. I'm just not sure what path I'd like to take regarding it if I find any issues - 1) delete the CCV system 2) replace with catch can system 3) repair existing CCV system with new parts

[Mless5]

Replace with new parts.

[legobumb]

Just going to give a small update here regarding the last couple of weeks and what I've done. If I remember correctly, since my last post I've replaced the lower intake boot (the elbow that sits on the throttle body), the vacuum line on the F-connector coming from the upper intake boot and going into the little vacuum pump, the oil dipstick tube O-ring and the 2 dipstick O-rings, and then finally my camshaft position sensor. While I was doing my camshaft position sensor (I started getting a P0340 code), I had to disconnect the CCV hose going into the valve cover and I noticed that the connector bit is coming loose from the hose, which is probably (and by that I mean most likely) the cause of my vacuum leak. I got a new fuel filter anyways just to be safe since I've driven this car over 60k miles now and never replaced it, and I have no idea if the previous owner (or any before them) had replaced it ever. Tonight I'll order a new CCV hose and tomorrow I'll probably clear the codes and drive around a bit to see if anything has improved. Letting it idle today after replacing the camshaft position sensor, it definitely feels like it idles much easier, but does the tiniest bit of shuddering after idling for longer than a minute, but it's no where near as bad as it used to get. So I think it's safe to say I've made some progress. I've definitely become quite familiar with my engine compartment these past few weeks, haha.

On a side note, the new camshaft position sensor was actually much girthier than the old one. Anyone know why? It still fit because the newer one was still the same size as the base of the old one, but the old one's sensor itself was thinner. Is it because the newer technology just warranted a larger size? Or is the newer one just more sensitive than the old one? Or allows for wider tolerances?

[MIKYZZ4]

Just be sure to replace ANY electrical/electronic component with ONLY original BMW OE or OEM replacement parts.

[legobumb]

The camshaft position sensor, I got from FCPEuro and it's VNE Automotive branded which the site says is OE.

[MIKYZZ4]

You should be fine, considering FCPEuro is the source.

[legobumb]

So I got around to putting in a new fuel filter today, as well as a new piece of vacuum line for the fuel pressure regulator. After fighting to prime the line enough to finally get the car to stop misfiring (turn key to on position a few times, started the car, rev'd the engine a little, turned engine off, repeat until car stops misfiring at idle), I noticed that after revving the engine, the engine will drop to about 1000 RPMs and hang for a second before dropping to the normal idle RPM of about 600-700. Is this normal behavior? This happens even while actually driving and I take the car out of gear to let it coast and not just while at a standstill and I rev it a bit. Is there something I can check to make sure I didn't accidentally mess up in the process of replacing the fuel filter? Will this eventually go away?

EDIT
Actually, after going for a few mile drive (and not just around the block from earlier), the RPMs started going down to actual idle without issue. I was just being paranoid and pre-emptive with my worries. Tomorrow before I go out for work, I'll clear the codes again and see what (if any) comes back. I drive a lot for my job (about 500 miles per week average), so there'll be plenty of time for my car's systems to re-calibrate and reset and what-not.

[harrier]

Getting codes gone is great! But not quite done.

Now check your long term fuel trims. I suspect they are still high.

Have you done a fuel pressure test?

[legobumb]

That same day, the codes came back after driving about 70 miles or so. Specifically the P1092 and P2096 but after another 100-150 miles, I got like every lean code imaginable lol. P0171, P0174, P1083, P1085, etc

Today I took out the entire CCV system. There was definitely a broken valve cover vent hose. Not sure if anything else was broken because I basically broke it all as I was taking it out. The valve itself was quite annoying to get out. But I bought basically the entire CCV kit from FCPEuro, minus the lower intake boot because I already replaced that piece. Tomorrow I'll be putting in all the new stuff, clearing the codes, and probably doing a test drive. I'm crossing my fingers after that because I really don't have the equipment to do compression tests or fuel pressure tests. But I suspect the next thing would have to be the brake booster only because it's legit the ONLY thing I haven't replaced yet. I've done literally about everything else.

Valve cover gasket, upper and lower intake boots, DISA valve gasket, secondary air pump vacuum hose and the hose going between it and the check valve, hose coming off the F-connector of the intake boot that goes into the air pump nearby (the thicker hose) as well as the vacuum hose coming off the same F-connector, oil dipstick tube O-ring and the O-rings on the dipstick itself, camshaft position sensor (I know that isn't vacuum leak related but I did do it in the process because I got that random P0340 code or whatever it is), and even the fuel filter and its vacuum hose for the pressure regulator. I guess I could check the fuel pump as well, but I'd rather do a fuel pressure test before I even entertain that idea. Checked the Idle Control Valve and it's nice and flappy when I shake it so I know that isn't the issue. I even sprayed it out with some WD40 to clean it a bit. I honestly doubt the MAF sensor is the issue since having it unplugged only causes immediate rough idling issues as opposed to it taking a bit before rough idle happens.

[legobumb]

Put in the completely new CCV system today, cleared the codes, then went on a decent test drive (probably about 20 miles or so), and I got all the same pending codes (P0171, P0174, P2096, P1083) and even 1 confirmed code (P1085). So I'm clearly missing something. I do hear a low tone whistling or air rushing sound at moderate throttle though. Not sure if that's normal. Googling around says high pitch whistling is usually the brake booster, but my brakes feel fine. I think at this point, I'm just going to take it to a shop that specializes in BMWs and see what they diagnose. I'm tired of taking apart my engine bay at this point in time. At least I shouldn't have to worry about any of those parts for quite some time!

[MIKYZZ4]

Check fuel pressure at fuel rail Schrader Valve via a Fuel Pressure Gauge available for rent at local auto parts store.
Perform another smoke test to confirm no new leaks are present.

[legobumb]

Just tried using a fuel pressure tester from both AutoZone and O'Reilly's and neither one had a snug enough schrader adapter. Is there one sold somewhere that does have the appropriate adapter for my car?

EDIT
I brought the car to a mechanic yesterday to see what they think is going on. They have the $15,000 DME scanner or whatever to get the BMW-specific codes. About an hour after I left it there, they called me saying there's a ton of codes going on all over the place - lean codes, secondary air system codes, both pre- and post-cat oxygen sensors are reading wrong. They told me they can't really isolate the issue until the exhaust leak is addressed. The connection between bank 1's exhaust manifold and the post-cat pipe was broken. Which is literally right next to the post-cat oxygen sensor and they say it's causing a massive exhaust leak and the sensor will never be able to read correctly because of it. So I told them to see what they can do about re-connecting that segment of pipe. The old bolts were rusted so bad that I guess they broken. Pretty typical e46 issue. They didn't call back again after that so I'm assuming they're either still driving it to see if any codes pop back up, or haven't even plugged the exhaust leak yet. :\

[legobumb]

Okay so the mechanic says he managed to plug the exhaust leak. They cleared the codes and drove about 8 miles before getting misfire codes on all of bank 2 (cylinders 4, 5, & 6) as well as "fuel trim deviation" and "fuel trim limit" codes. They think it might be the head gasket and recommend I get a compression done first before trying to proceed with anything else. They also mentioned my radiator fan doesn't turn on - something about low speed and high speed not working. I've never had the engine overheat on me this whole time though, so I guess I'm just lucky? Or maybe the fan recently died, idk.

Not really the news I wanted to hear haha. Looks like I've got my work cut out for me. I definitely want to try and do my own head gasket if it comes to that. Save myself a ton of money that way.

[Critter7r]

My electric fan hasn't worked in about 5 years. M54 has a belt driven fan to cool the engine, the electric fan is just to handle excess, and to turn on with the A/C. I've never overheated even when idling for extended periods of time in traffic.

I don't know that I've ever heard of a bad head gasket on an M54 engine without an overheating episode. Mine is just about to turn 300k, no issues.