Hi all.
I purchased a 2005 530D in October last year, its an Ex BMW fleet car with high milage (116K miles) but it drives excellent apart from a bad engine hesitation after changing gear (its a manual )

I have a lot of experience with CR diesel engines (I work for an FIE supplier, not a German one (hint, hint))

So my first thought was an air problem, I removed the EGR vacum hose and the car drove great in all conditions, only problem was the CEL and slight increase in emissions
Drove it like this for a few months with no problems, however being a diesel engineer I wanted to solve the problem rather than hide it.

So last week I decided to look into the air system, I removed the inlet manifold to get at the EGR valve and the EGR controller valve, the EGR valve was horrid as expected, I cleaned it out and tested its operation using a vacum pump and it moved smoothly, checked the controller valves filter (clean) tested its operation on a test vehicle at work where I can record all airflow data and it worked as expected.
Put it all back together and everthing seemed fine at first but after a quick stop to get fuel the hesitation was back.
It seems to be temperature related, the fuel stop allowing temps. to increase in the engine bay and I assume activate the EGR system when I restart?

My next thing to try is a new AMF sensor but before I do I wondered if anyone else had had a similar problem?

Thanks
Jason

 

It could be so many different things-

1. Try disconnecting the MAF and drive a short distance to see if problem is still present, if it's not then there's your problem. Can be cleaned very carefully using electrical contact cleaner. (something that leaves no residue)

2. When was the last time your air and fuel filters were changed, if they are in poor condition then that won't help.

3. Make sure the the engine breather has been changed to the new vortex type.

4. If the CEL light is on get the codes read.

I thought that the CEL only came on after you had the inlet manifold off and disabled the swirl flaps, maybe you had a pre-existing fault and this was just coincidence.

 

Agreed, MAF's are still a big problem for BMW sadly

Always buy genuine Bosch replacements however, im told in many places the cheap "ebay" clones are next to useless sadly.

Having seen the contents of my 80,000 mile E46 320d EGR I shudder at the thought of doing my E60 ( now similar mileage ), especially as it seems you cannot simply bypass it like I did on my 46

Good luck

 

I'll try the MAF disconnecting test.
The car had a full sevice after I bought it so all filters including breather are new.
I know someone who can read and clear all generic and BMW faults so ok on that front. The CEL is always on / off as I keep playing

Just contacted BMW and they want ?250 for a new MAF so will try cleaning first.

Jason

 

Thats normal

GSF ( German Sweedish and French ) in the UK normally save you around ?50 for the same part however

 

I assume you know air filters are replaced every 3rd service, I average just under 20K to a service so replacement would be at 60K and 120K so you might be due an air filter replacement

 

I had a major service and everything was replaced, even if it didn't need to be so I started ownership from a known position.

Jason

 

How bad is the hesitation ? is it a turbo lag hesitation or an engine stutter ?

If turbo lag check intercooler pipework isnt leaking ?

 

it could be the whole inlet manifold coked up with gunk. try removing it and cleaning out. goood tread on here anzafin. major diesel failure.