[Bootdog]

Any update?

Any update on this?

I have a very similar problem on my remapped 320d, hesitation at 1500 rpm, also higher up the revs when feathering the throttle. It also seems very smokey which it wasn't before, but fuel economy is still excellent.
I've a new DMF and clutch, and the swirl flaps are removed, so I can rule those out.

Thinking of changing the MAF and air filter first.
Also any guides on EGR cleaning?

 

[shane aka 320d]

Have to say i stopped using diesel from the Apple garages and have being using statoil stations instead and the hesitation is no where near as noticeable, its not gone completely luv no where near as bad.
I also used some diesel treatment stuff aswell.

 

[Bootdog]

Further update:

Changed the MAF for a new one - no difference
Air filter changed - no difference
EGR cleaned out - slight improvement, but still present
Fuel filter replaced & fixed split in a turbo hose - slight improvement, but still present

Diagnostics showed there is a flow imbalance on one of the injectors, but not too big.
Next stop injector cleaner and changing fuel supplier.

On a more positive front, the mpg has gone up a lot since the hose repair and fuel filter. I managed to get 67 mpg on a 60 mile run today, so there can't be too much wrong with it!

 

[Bootdog]

Another update - tried injector cleaner, tried a new supplier - the good stuff, BP ultimate diesel.
Smoking was much reduced, but hesitation still present, although much reduced.

I've gone back to the normal fuel, and there's much more smoking, and more hesitation.

 

[DavidK]

did you get the manifold cleaned?
was it a genuine maf?
Have you had the car scanned or checked for boost leaks?

 

[Dicko]

Sounds like you egr is a bit slow closing , I disconnected mine for a laugh and its amazing how much faster it responds at low rpms , remember if the egr is open you won't get any boost till it closes . Try running it with the egr vacume line disconnected it will bring on the check light but at least you will know , I have replaced a few of the control valves on them it could be a bit sticky .

 

[Bootdog]

MAP Sensor

Update - I popped out the MAP sensor and gave it a clean, and hey presto, hesitation is gone today. I'll have to monitor it for a few days to be sure.
Smokiness is also pretty much gone.

MAF was genuine, and no codes present.
What should I look out for in the manifold that would need cleaning?

 

[danbarr]

Had a buddy with a 320CD in about a week ago with very similar problems. Hesitation around 1500-1700RPM but only on gradual acceleration, when you put the shoe down it was fine. Turned out to be the actuator for the swirl flaps sticking. Freed it out and problem solved. You may have tried all this already but it is a similar problem may help someone else.

 

[Bootdog]

The swirl flaps were removed on mine, seems there's a few problems that cause similar effects.

 

[Bootdog]

EGR vacuum controller

I finally got this sorted - the vacuum controller / pressure converter to the EGR valve was the issue. There is a small membrane/filter which was blocked - I pulled this off, and the existing vac controller seemed to work OK, but I replaced it anyway with a new unit including a new filter. No issues for the past 2 weeks.
Info here: http://www.bmwland.co.uk/forums/viewtopic.php?t=68028&postdays=0&postorder=asc&highlight=engine++picture&start=0

I had changed a few things before this :
Changed the MAF for a new one - no difference
Air filter changed - no difference
EGR cleaned out - slight improvement, but still present
Fuel filter replaced & fixed split in a turbo hose - slight improvement, but still present
Injector cleaner & new fuel - not much change
I also checked the vortex breather filter - it was spotless (changed 40k miles ago)

 

[Daithi1]

320d 2004

Same or similar problem here, shuddering at low revs, Replaced the fuel filter but problem persists. Ive had a look at the uk forum re: egr pc and that seems to be a solution. I will get the part from the dealer and report back.

Heres hoping, and thanks for the info..

 

[Bootdog]

Was this happening in warm weather?

My problem has recurred in warm weather - above about 14 DegC it will stutter a bit. I've removed the hose to the EGR PC so that it can't operate and plugged it with a screw, so will monitor over the next few weeks.

 

[Daithi1]

it happens in all weathers, I just got the part and hope to fit it this saturday, are your tubes ok? Ill let you know how I get on, sorry to hear of your news, I was getting excited there.

 

[MAR]

hesitation at 1500 revs in 3 & 4

Hesitation became more apparent after oil / fuel filter/ engine air filter change. I have tried to find patterns when it occurs, all that I can report is it happens when the engine is hot (typically after 10/15 miles of driving). It happens when I drive with a light foot.

Bootdog - I am still curious about your findings.

I plan to use an injector cleaner (Wynn's) for the first time and see the effect.

 

[Daithi1]

I just spoke to another BMW owner. He tells me he had the same problem and it was his fuel pump failing. And it was sorted when he replaced this fuel pump. Bootdog, did you replace yours? I hope to get mine tested soon.

UPDATE: I got a mechanic to have a look this morning and his diagnostics reported low pressure in the fuel delivery, Exactly how it feels, So, we can narrow this down to either of the fuel pumps, But it looks more like it is the electric pump, under the car. Ill replace this part asap and report back. This was the second person to tell me it looks like it is the fuel pump that is failing.

Hope this helps.

 

[Halley17irl]

Any update on this issue or anyone actually solved it?

 

[Daithi1]

Solution?

For the benefit of the thread. My mechanic cleaned the contacts on my reverse lights on saturday when I noticed one was not working, Since this time there has been little or NO hesitation in my car. I have had problems in the past with corrosion and have read numerous accounts of an earthing problem common to 320ds.

I wonder have I found the solution? Two journeys since, of an hour each, allowing the car to reach maximum operating temperature and not a sign of hesitation.

Hope this helps.

 

[Bootdog]

Mine is definitely EGR related:

As mentioned below, I disconnected the Pressure Converter and ran it until yesterday like that. There was not a single occurrence of the hesitating, and much less smokiness, I would have covered around 600 miles like this.
As it was a good hot day yesterday, I pulled in while the car was warm and undid the change - removed the screw and reconnected the hose. As soon as I pulled away the car was noticeably more sluggish, the hesitations returned and it smokes more under hard acceleration too.

 

[Daithi1]

Still have the hesitation at low revs. I am about to fit a new fuel pump this weekend and hope this sorts it.. Diags show low pressure and mechanic has advised I buy a new pump. However, yesterday My diags show low voltage on pwg readings, this would suggest that there may be some problem with the throttle. Ill be looking into that if the fuel pump doesnt sort it.

 

[Halley17irl]

EGR! Can be disabled through software if anyone is any good with bmw coding it can be done and gives no light up on the dash and runs much smoother low down rpm with no hesitations..