Hi. My Dad has his 2nd BMW!  He had an X3 and decided he wanted an X5.  He’s a bit of a boy racer at 77!  Anyway, he’s only had it a couple of weeks and it seems to lose power occasionally. Not every time he drives it, not only first thing in the morning, just as and when. A BMW specialist did a thorough computer test and no faults. No warning lights. Drove like a dream on the test drive. He told my Dad it’s most likely it needs a new particulate filter and quoted £3,000. My husband is a mechanic (40 years experience) but mostly fixes classic cars.  Any advise would be greatly appreciated. Many thanks.  

Morning Carol Welcome to the forum.

I am the same age group as your Dad, remember we can't stop getting older but who said we have to grow up??

A loss of power can be many things apart from the DPF, blocked fuel filter, failing fuel pump, throttle body fault, leaky or faulty injectors the list is long.

I don't drive a diesel but have son's and a daughter who do, what I have learned is the DPF (diesel particulate filter) is pretty much indestructible. Yes they clog especially when used for short journeys but there is a regeneration program built in which can be triggered by a good knowledgeable garage with the correct software. The regen programs can also be triggered by driving the car, a good blast in 3rd gear to keep engine revs at about 3k (sons Toyota pickup) this cleans the DPF you can also get them chemically cleaned talk to a diesel specialist.

I would check that the specialist he has talked to has actually read the codes? A blocked DPF will certainly trigger lights and engine codes plus they can't be reset if there are other associated faults such as EGR (exhaust gas re-circulation) blocked, injector or glow plug faults. 

I would be talking to a different garage, check out your area for a good diesel specialist or Landrover specialist (same engine in the Range Rover) also google DPF regen and read up.

Good Luck

Dave

 

5 hours ago, Greydog said:

Morning Carol Welcome to the forum.

I am the same age group as your Dad, remember we can't stop getting older but who said we have to grow up??

A loss of power can be many things apart from the DPF, blocked fuel filter, failing fuel pump, throttle body fault, leaky or faulty injectors the list is long.

I don't drive a diesel but have son's and a daughter who do, what I have learned is the DPF (diesel particulate filter) is pretty much indestructible. Yes they clog especially when used for short journeys but there is a regeneration program built in which can be triggered by a good knowledgeable garage with the correct software. The regen programs can also be triggered by driving the car, a good blast in 3rd gear to keep engine revs at about 3k (sons Toyota pickup) this cleans the DPF you can also get them chemically cleaned talk to a diesel specialist.

I would check that the specialist he has talked to has actually read the codes? A blocked DPF will certainly trigger lights and engine codes plus they can't be reset if there are other associated faults such as EGR (exhaust gas re-circulation) blocked, injector or glow plug faults. 

I would be talking to a different garage, check out your area for a good diesel specialist or Landrover specialist (same engine in the Range Rover) also google DPF regen and read up.

Good Luck

Dave

 

 

Thanks Dave. 

I have told Dad and he has phoned the dealer who he bought the car from and he has asked for the opportunity to fix it!  I’ll let you know what they say. 

Regards

Carol

Hi Dave

The dealer had the DPF cleaned as it was partially blocked. Drove fine for 2 days. Once since he got it back it has the same problem. He turned it off, waited a few minutes and it was fine again!

Dad is quite savvy and got in touch with previous owner who said it had to EGR, new glow plugs before he sold it. 

Going to see how it is for a few days, but just thought I’d update. 

Regards

Carol 

Hi. 

 

Strangely the problem is still intermittent. My husband fitted a new throttle body. It drove like the wind for 2 days, then when taking my mum to hospital it decided 40 mph was the optimum speed. 

Many other ideas? 

PS no codes showing at all! 

 

Morning Carol

If the car has decided "restricted engine performance" a fault has triggered that.

When you say "no codes showing" are you using a BMW specif reader/scanner, if not it will only give very limited information and general codes. Below is a screen shot from BMW 1.4.0 (the program I use) it gives fault information in English as against numbers which need to be compared to a fault list. Depending on it's build spec your X5 could have 3 pages of modules, sensors and control units. As an example my drivers heated mirror stopped clearing plug in and it tells me I have an open connection/broken wire in the drivers door mirror.It is cheap and can be loaded on a laptop, there is also Carly for BMW you can use that on a laptop or smartphone.

If you or your garage are using a general code reader then fault finding can be difficult and costly as you end up throwing money at the problem, another example my Brother inlaws 535 estate had the EML his local guy said oxygen sensor a few hundred quid later the light is back when we investigated it was a perished vacuum hose.

First I would check all the simple and low cost items starting does the problem happen when fuel levels are low 1/4 tank or less check the fuel filter the fuel filter (often forgotten at service) can restrict fuel flow. If the last owner had the egr replaced I would check it isnt blocked again so many of the engine fuel air delivery systems are interlinked that one faulting will have a knock on that masks the true culprit which is why a good code reader is needed along with a multi meter to test connections.

 

Hi Greydog

My husband is a mechanic and used his Snapon Solus code reader, then my Dad’s local garage (don’t know what they used). Then a BMW specialist with computers. 

My husband is going to look at the programmes you mentioned. It’s so frustrating as it’s such a nice car. He will also look at EGR and fuel filter as he hasn’t personally checked them. 

Thank you

Carol 

Dave

Ive looked on EBay for BMW 1.4.0 but it doesn’t list E70. Is it compatible for all BMW’s. They range from £14 up, so quite cheap, but want to get the right one. 

Thanks again

Hi Carol

I have used my version which is at least 8 years old now on my brother in-laws 535 which is a 2014 manufacture so I would think a current set of software would read up to date.

When I brought my version it could only be used with windows 7 and I know that new versions can be used with Windows 10, 

There is also Carly for BMW which I know others use.

Dave