320d feels flat

chrissyw · 08-15-2018, 09:10 AM

Noticed the last couple of months my 320d seems quite flat.

It’s low down in the Rev range around 1,500-2,000 I really have to put my foot down to get it moving.

It’s been mapped to 207bhp and had an egr delete kit. It’s also had new maf sensor about 1,500 miles ago.

It just seems really hesitant low down.

I’ve noticed with the window down when the boost kicks in there is a really loud distinct hissing noise. Now I know it’s normal to hear the turbo spooling but this is loud.

Turbo was reconditioned at 70k, it’s on 150k now.

Any ideas?

N5GKP · 08-15-2018, 10:29 AM

Quote:

Originally Posted by chrissyw

Noticed the last couple of months my 320d seems quite flat.

It’s low down in the Rev range around 1,500-2,000 I really have to put my foot down to get it moving.

It’s been mapped to 207bhp and had an egr delete kit. It’s also had new maf sensor about 1,500 miles ago.

It just seems really hesitant low down.

I’ve noticed with the window down when the boost kicks in there is a really loud distinct hissing noise. Now I know it’s normal to hear the turbo spooling but this is loud.

Turbo was reconditioned at 70k, it’s on 150k now.

Any ideas?

Have you checked the charge air pressure pipes from the turbo to inter cooler & intercooler to intake manifold? Also worth checking the intercooler for any obvious damage too

Nel2014 · 08-15-2018, 12:30 PM

Maybe worth getting the fault codes read as well.

chrissyw · 08-15-2018, 02:57 PM

The intercooler to intake manifold pipe is definitely ok.

The turbo to intercooler pipe I’ll have a look at, it’s definitely louder on the drivers side, which is where the turbo is obviously.

Do you guys recommend a fault code reader I could buy to read the codes?

rasa bmw · 08-15-2018, 05:25 PM

will probably be the red boost hose,,well i think it will be red like on the 330d,,is your revs going up quickly but car not going as fast as it should ..? as if clutch was slipping..also check all vacuum lines.

therealdb1 · 08-15-2018, 05:49 PM

Quote:

Originally Posted by chrissyw

Do you guys recommend a fault code reader I could buy to read the codes?

My favourite is proper BMW INPA with the suite that allows you to carry out coding too.
The downside is you will need a laptop and depending where you source the software it can be a PITA to install on the PC.
Once you have it working you will not look back but I'm sure the Carly fans will be along shortly as will fans of every other Android / iPhone App and users of a dozen different hand-held readers.

If you intend keeping the car for any length of time some kind of reader is a worthwhile investment as for the cost of a single code read at a garage you can buy your own and use it indefinitely.

therealdb1 · 08-15-2018, 05:54 PM

Quote:

Originally Posted by chrissyw

It just seems really hesitant low down.

I’ve noticed with the window down when the boost kicks in there is a really loud distinct hissing noise.

This sounds like your turbo is trying to pressurise the atmosphere!

Almost certainly a leak in the induction pipework somewhere. Is the wastegate stuck open?

Remember the turbo has done more miles since it has been reconditioned than it did before it was reconditioned last time!

bishbosh · 08-17-2018, 02:15 PM

The 320d doesn't have a red boost hose. The hissing noise certainly sounds like a boost leak though.

Get a mate to rev the motor while you locate the source of the leak - it's easier to find leaks that way.

rasa bmw · 08-18-2018, 12:53 AM

then the hose will be black,,from turbo to ic..pretty sure if its a wooshing sound it will be this.

Paul D3 · 08-18-2018, 06:20 AM

Sounds like the turbo vanes could be stuck/sticking

chrissyw · 08-20-2018, 04:14 AM

Gave it a blast a bit over the weekend and noticed it's got a couple of flat spots through the rev range, it hesitates a bit at 2,700 rpm and then 3,800 rpm.

I thought at first it was wheel spin but the DTC light isn't flashing so I don't think it is.

Is there just 2 main hoses to check? One from the turbo into the intercooler and the other going into the inlet manifold?

N5GKP · 08-20-2018, 07:20 AM

Just a thought, have you looked at the reluctor rings on the rear drive shafts? If yours is the model with exposed reluctors they're prone to corrosion which can distort them & also damage the wheel speed sensors and cause 'flat spots' whilst driving. It starts off periodic but when it gets worse the car will jerk a lot at any speed.
Best bet is jack the rear, and have a look at the drive shaft reluctor near the hub, if it's noticeably shiny compared to the rest of it that could potentially be the issue

scuddy100 · 08-28-2018, 05:03 PM

Hi mate.. I'm having exactly the same issues.. so annoying
Did you manage to find the problem off the hissing sound??
Cheers
Lee

chrissyw · 09-27-2018, 03:00 PM

Quote:

Originally Posted by scuddy100

Hi mate.. I'm having exactly the same issues.. so annoying
Did you manage to find the problem off the hissing sound??
Cheers
Lee

Nope it's still doing it mate.

Could do with getting it up on some ramps really.

Len_Beach · 09-27-2018, 03:23 PM

Clean your MAF and MAP sensors.

chrissyw · 12-07-2018, 09:24 AM

I replaced the MAF with a Bosch and cleaned up the MAP sensor, it revved freely.

Issue is now back, i've cleaned up the MAP, the MAF is fine and the easiest way to describe is someone flicking the 'full power' switch at about 3,200 RPM and it suddenly bursts into life.

Turbo looks perfect, looks pretty much new tbh. Blades feel nice and tight, no play.

Checked all the piping, on and tight.

No fault codes.

No smoke.

Strange one, which has now left me confused.

therealdb1 · 12-07-2018, 09:38 AM

If it is still hissing you still have an air leak somewhere.
It may not necessarily be at the turbo but could be any of the pipes in between the MAF to the inlet manifold. Could be something as simple as a vacuum pipe to the brake servo.
Sometimes the splits in the hoses are almost impossible to see and you really need to squeeze and move them around and listen for a change in hiss to narrow it down.
There are no shortcuts I'm afraid it is just a case of logical perseverance.
Start at the MAF and follow the airflow through the system until it enters the inlet manifold making sure that you check all offshoots along the way.

08-15-2018, 09:10 AM	#1
chrissyw Second Lieutenant 42 Rep 229 Posts Drives: 2006 E90 320d M Sport Join Date: Mar 2014 Location: Midlands iTrader: (0)	320d feels flat Noticed the last couple of months my 320d seems quite flat. It’s low down in the Rev range around 1,500-2,000 I really have to put my foot down to get it moving. It’s been mapped to 207bhp and had an egr delete kit. It’s also had new maf sensor about 1,500 miles ago. It just seems really hesitant low down. I’ve noticed with the window down when the boost kicks in there is a really loud distinct hissing noise. Now I know it’s normal to hear the turbo spooling but this is loud. Turbo was reconditioned at 70k, it’s on 150k now. Any ideas?
	Appreciate 0 Tweet Quote

08-15-2018, 12:30 PM	#3
Nel2014 Banned 24 Rep 248 Posts Drives: BMW 320d Join Date: Dec 2014 Location: Bedfordshire iTrader: (0)	Maybe worth getting the fault codes read as well.
	Appreciate 0 Quote

08-15-2018, 02:57 PM	#4
chrissyw Second Lieutenant 42 Rep 229 Posts Drives: 2006 E90 320d M Sport Join Date: Mar 2014 Location: Midlands iTrader: (0)	The intercooler to intake manifold pipe is definitely ok. The turbo to intercooler pipe I’ll have a look at, it’s definitely louder on the drivers side, which is where the turbo is obviously. Do you guys recommend a fault code reader I could buy to read the codes?
	Appreciate 0 Quote

08-15-2018, 05:25 PM	#5
rasa bmw Colonel 246 Rep 2,025 Posts Drives: 640d sport/f31 330d x drive Join Date: Jul 2017 Location: northumberland iTrader: (0)	will probably be the red boost hose,,well i think it will be red like on the 330d,,is your revs going up quickly but car not going as fast as it should ..? as if clutch was slipping..also check all vacuum lines.
	Appreciate 0 Quote

08-17-2018, 02:15 PM	#8
bishbosh Colonel 983 Rep 2,165 Posts Drives: F30 335d Join Date: Oct 2013 Location: Sheffield iTrader: (1) Garage List 2014 BMW 335d [0.00]	The 320d doesn't have a red boost hose. The hissing noise certainly sounds like a boost leak though. Get a mate to rev the motor while you locate the source of the leak - it's easier to find leaks that way.
	Appreciate 0 Quote

08-18-2018, 12:53 AM	#9
rasa bmw Colonel 246 Rep 2,025 Posts Drives: 640d sport/f31 330d x drive Join Date: Jul 2017 Location: northumberland iTrader: (0)	then the hose will be black,,from turbo to ic..pretty sure if its a wooshing sound it will be this.
	Appreciate 0 Quote

08-18-2018, 06:20 AM	#10
Paul D3 Private First Class 72 Rep 182 Posts Drives: Alpina D3 Join Date: May 2015 Location: UK iTrader: (0)	Sounds like the turbo vanes could be stuck/sticking
	Appreciate 0 Quote

08-20-2018, 04:14 AM	#11
chrissyw Second Lieutenant 42 Rep 229 Posts Drives: 2006 E90 320d M Sport Join Date: Mar 2014 Location: Midlands iTrader: (0)	Gave it a blast a bit over the weekend and noticed it's got a couple of flat spots through the rev range, it hesitates a bit at 2,700 rpm and then 3,800 rpm. I thought at first it was wheel spin but the DTC light isn't flashing so I don't think it is. Is there just 2 main hoses to check? One from the turbo into the intercooler and the other going into the inlet manifold?
	Appreciate 0 Quote

08-20-2018, 07:20 AM	#12
N5GKP Private 16 Rep 91 Posts Drives: E90 325i M Sport Join Date: Jul 2018 Location: Preston, Lancashire iTrader: (0)	Just a thought, have you looked at the reluctor rings on the rear drive shafts? If yours is the model with exposed reluctors they're prone to corrosion which can distort them & also damage the wheel speed sensors and cause 'flat spots' whilst driving. It starts off periodic but when it gets worse the car will jerk a lot at any speed. Best bet is jack the rear, and have a look at the drive shaft reluctor near the hub, if it's noticeably shiny compared to the rest of it that could potentially be the issue __________________ Current: 2009 E90 325i M Sport Auto Previous: 2017 435d xDrive Gran Coupe, 2010 E90 318d SE, 2009 E90 318i SE.
	Appreciate 0 Quote

08-28-2018, 05:03 PM	#13
scuddy100 New Member 0 Rep 8 Posts Drives: 2005 bmw e90 saloon Join Date: Oct 2017 Location: Basingstoke Hampshire iTrader: (0)	Hi mate.. I'm having exactly the same issues.. so annoying Did you manage to find the problem off the hissing sound?? Cheers Lee
	Appreciate 0 Quote

09-27-2018, 03:23 PM	#15
Len_Beach Major 191 Rep 1,245 Posts Drives: 435d Join Date: Jun 2011 Location: UK iTrader: (1)	Clean your MAF and MAP sensors.
	Appreciate 0 Quote

12-07-2018, 09:24 AM	#16
chrissyw Second Lieutenant 42 Rep 229 Posts Drives: 2006 E90 320d M Sport Join Date: Mar 2014 Location: Midlands iTrader: (0)	I replaced the MAF with a Bosch and cleaned up the MAP sensor, it revved freely. Issue is now back, i've cleaned up the MAP, the MAF is fine and the easiest way to describe is someone flicking the 'full power' switch at about 3,200 RPM and it suddenly bursts into life. Turbo looks perfect, looks pretty much new tbh. Blades feel nice and tight, no play. Checked all the piping, on and tight. No fault codes. No smoke. Strange one, which has now left me confused.
	Appreciate 0 Quote

12-07-2018, 09:38 AM	#17
therealdb1 Lieutenant 106 Rep 575 Posts Drives: Graphite E93 335i Join Date: Aug 2017 Location: Norfolk UK iTrader: (0)	If it is still hissing you still have an air leak somewhere. It may not necessarily be at the turbo but could be any of the pipes in between the MAF to the inlet manifold. Could be something as simple as a vacuum pipe to the brake servo. Sometimes the splits in the hoses are almost impossible to see and you really need to squeeze and move them around and listen for a change in hiss to narrow it down. There are no shortcuts I'm afraid it is just a case of logical perseverance. Start at the MAF and follow the airflow through the system until it enters the inlet manifold making sure that you check all offshoots along the way.
	Appreciate 0 Quote