Possible turbo issue? Engine much louder under acceleration & less go at speed

[X5Sport]

It's not something really silly like an airflow issue is it?  As in a blockage somewhere in the intake path between the bonnet inlet point and air filter etc?

I might be clutching at straws, but just in case.......

[Horizon]

Blocked air filter, starving it of air

[Upex]

Unfortunately not, checked all that very early on and have replaced air filter twice.

No error on charge pressure anymore either, since cleaning everything and changing vac controller.

I just get why opening EGR would make it sound better at idle, everything I'm reading says the opposite. Doing my head in!

[ianst0028]

Is there an egr replacement kit for the 3.0?
Like a blank off kit..... Sounds to me like maybe the egr valve is dieing
I've not read that you've replaced it but if you have ignore this post lol
I was about to say that the discovery 3 has a weak egr but then I remembered that it's a 2.7 not the 3.0

[Upex]

If EGR is the cause, do we think it's failed closed? As surely that's ok normal for idle, but would then suffer driving?

If failed open, why would applying manual vac (to open it) at idle then make engine quieter?

Cleaned and tested EGR, it held petrol at the egr entry point, no leakage at all, and opened and closed with manual vac. Will try a drive with the EGR unplugged (and vac line blocked of course).

Anyone know what vac pressure should open EGR? As perhaps it's working, but needing more pressure than it should?

Also, anyone know what vac pressure should be at get and turbo, when at idle, as I would have thought them to be same, but I've hot .4/5 at EGR and .8 at turbo?

[Upex]

What's folks thoughts on a partially clogged cat or muffler?

I believe that would lose power, and make engine sound louder, and go quieter again when get EGR held open manually. As the car doesn't have any exhaust sensors, would this also explain no codes, or would we expect the map to be off with having too much back pressure?

Only thing I don't get is why the car can still red line and hold high speeds, surely it'd throtal it more at higher revs?

How can I test this theory out without buying a new exhaust system? Is it ok to disconnect flex from turbo and start her up, or will flame / very hot gases soon melt everything nearby?

Doing my head in!

[Horizon]

[quote="Upex"]
What's folks thoughts on a partially clogged cat or muffler?

I believe that would lose power, and make engine sound louder, and go quieter again when get EGR held open manually. As the car doesn't have any exhaust sensors, would this also explain no codes, or would we expect the map to be off with having too much back pressure?

Only thing I don't get is why the car can still red line and hold high speeds, surely it'd throtal it more at higher revs?

How can I test this theory out without buying a new exhaust system? Is it ok to disconnect flex from turbo and start her up, or will flame / very hot gases soon melt everything nearby?

Doing my head in!
[/quote]
I had a blocked / collapsed cat on my 840 CI M62 V8 . It threw up misfire cylinders 5,6,7,8. It would run fine until you planted the gas pedal in the carpet and then after a few seconds would go into limp mode.
I called at my indie and They wanted to start by replacing 4 coilpacks to start with as well as 4 sparkplugs. !!!!
One of the old timers asked me did the exhaust rattle in the morning when cold ? I said now you come to mention it , I hadn't noticed a rattle on startup.
As the cat had collapsed it was causing a restriction in the exhaust which wouldn't allow the exhaust gases to get out quick enough when on full chat.
This caused the EM system to go into limp mode.
So in my experience, a blocked cat will throw up a misfire fault code.
I'm sure someone on here had a similar problem too.

[X5-D-Sport]

Just by removing & looking into the EGR valve will tell lots, as they end up looking like they are full of dried tar.

Simply ditch the EGR valve as a matter of course, buy a straight thru replacement & the exhaust manifold blanker...
you will probably gain a few more MPG & a tinsy bit more power too. I ditch EGR valves as a standard procedure with any fresh vehicle, as they are a bloody pain.

[Upex]

Thanks horizon, although doesn't sound promising then.

Can't say there is any rattle at cold or otherwise, and car suffers all the way through rev range, doesn't get worse or trigger limp mode etc. Also no codes thrown even after redline action, but that said, you'll have had a sensor or two to help, but this diesel is without sensor according to realoem, which I find strange as a pre cat sensor would have been my first starting point to see if having it removed help with pressure lol.

I hear ya x5 d, but right now have to fix the issue before anything else. If being honest, I'm not that far off trading the car in or scrapping the bloody thing, so unless can fix it, have zero interest in spending even more koney on further preventative maintenance lol

[Upex]

So, bmw indi given up, can't find anything wrong.

Hasn't tested exhaust pressure mind, as doesn't have a gague, but it's unlikely as can be redlined.

I mentioned gear changes aren't as smooth and perhaps it's a clock up clutch issue, he thinks not and advised to not change aft after 135k miles likely untouched.

Leak down is a bit high on all injectors, but he said it wouldn't  be cuasing the issues as they are, without others etc.

Said old turbo (that I've put back on) is fine. Touch noisy but doesn't need replacing as first garage said. Said boost and fuel readings are ok Tec.

So call to bmw main dealer tomorrow to get her booked in. How much are they likely to be for diag time?

Utterly crapped out with this car lol.

[X5Sport]

Diagnostics only check is normally 30 mins.  Labour rates vary but it could be £100 for that.

[Upex]

Yuk, but appears to be last option. Cheers x5sport. Least if they 200 I know to haggle lol.

I just hope they can find the issue quick!

[Upex]

£120, booked in for next Friday.

Place your bets now folks, will they find something... If so what... will they ask for more time... or will they luck out...

Never used a main dealer before, so I'm playing to.

I reckon they will ask for 3hrs investigation time, then either say it's fooked, can't find anything, or it's very expensive (ie engine/gearbox replacement). I'm a 3rd on each, spread bet.

What recourse is there if they ask for more and more time and then come up with nothing?
Or if they say its X and I say do it, but after it's done, it's no different?

Fingers crossed!

[Upex]

So, spent the day in bmw and they haven't a clue as there are no codes. They drove it and said it feels normal.

Didn't and can't test exhaust back pressure, they don't have a gague and there no sensors on car so they can't test it or get a reading etc. I asked them to drill the darn thing and weld, but they refused.

Instead, they wanted to replace the air filter and test my swirl flaps... interesting, wonder where they are then... and this was after the first batch of diag was done and I asked what was next for testing when asking for more time.

I asked them to pressure test intake circuit, or at least inlet manifold, off they went. Later called back and they told me the map and air temp readings were normal, not what i asked for.

No clue and say to start delving without codes will be hours worth of cost and perhaps still not yield results.

So another waste of cash.

I'm picking up the paperwork tomorrow that is them confirming all is normal and everything engine/electrics checks out ok.

Anyone want to buy a diesel x5 sport?

[X5Sport]

Erm, the E53 3.0D with the M57 engine was never, ever fitted with swirl flaps!  It was the only variant that wasn't but a main Dealer damn well ought to have known that!  That shows yet another poor standard of technical knowledge from a BMW franchisee.  Not good enough!  >:(

They were fitted to other cars (our 2005 E46 with the same engine had them until I removed them) and the E70 and onwards have them.

They sit in the air intake side and modified the airflow at certain rev points by opening or closing.  Required for EU4 and beyond but the E53 was EU3 and did not need them.

I'm sorry you aren't getting anywhere though.    No fault codes or errors logged is frustrating but given they didn't know that you don't have swirl flaps says a lot about their diagnostic skills!  If the computer says it's fine then (according to them) that's it.  They won't have the ability to diagnose further without time and your money.

I don't know what to suggest next.  At £200 an hour and no further forward with a Dealer, and an Indy not helping you either this is getting puzzling and frustrating.  Is the gearbox OK?  Is the torque converter starting to misbehave as that could cause a power loss into the gearbox if it isn't coupling the fluid pressure over properly.