[E92westy]

Ok, so the car (E92 320i) is coming up for an oil service and I have already bought my own oil (Castrol Edge) but will go to the main dealer for the work to keep the full BMW service history going (for now…).

Car will be nearly 3 years old with 40,000 miles on the clock.

Since all the work has been done on my car (see my previous posts / rants!) it’s running OK, but still feels a bit flat on the odd day and the idle occasionally wobbles a bit – nothing bad enough for me to have had to take it back again, but will be mentioning it at service time.

I’ve read a lot about carbon build up, particularly on intake valves, in direct injection petrol engines, due to the fact that the fuel does not wash over them and keep them clean. This cleaning is now almost totally down to the engine oil. These carbon deposits can apparently cause poor idling and misfiring (ie the symptoms in my previous posts!).

It would appear to make sense to me, therefore, to add an engine flush at service to help to remove any carbon deposits. I’ve also read about engine flushes causing issues, but these seem generally on older and higher mileage cars.

So the question is,

· does the dealer add a flush at service themselves? (I will ask, but not confident of getting a straight answer).

· if not, should I add one myself for the above reasons?

· if so, should I use Forte Advanced Motor Flush, BG Quick Clean, Liqui Moly Engine Flush or anything else you can recommend?



Thanks for reading all that!

[doughboy]

Carbon on inlet valve heads is caused by oil mist fed back into the air intake from the crankcase breather system, there maybe some truth about DI engines not 'washing' the valves with fuel i'd say.

Engine oil cannot clean valves, there is no engine oil in contact with valve heads other than the waste oil mist described above.

But anyway, an oil flush will only flush the internal oil system, and of course will not touch valve heads.

IMO don't use an oil flush as you won't need one if your car has been subject to the correct oil changes so far in its life. It's a bit of an old school thing, like redex treatments and all that guff.

EDIT (just seen post 3):

You don't ADD engine flush, you remove the oil, then 'flush' through with the flush cleaner, then replace with new oil.

Are you talking about and oil additive or an oil flush??

[creepy coupe]

Engine flush is an engine oil, designed for cleaning crud out of high mileage engines. Do you mean an additive, such as injector cleaner?

[E92westy]

I'm talking about flush, not additive.
Like this:-

http://www.forteuk.co.uk/product.php

"Forté Advanced Formula Motor Flush will provide the following benefits:

•Clean engines internally and provide anti-wear protection
•Free sticking piston rings, hydraulic valve lifters and variable valve timing systems
•Remove lacquer, varnish and sludge deposits from the crankcase
•Neutralise crankcase acids, keeping new oil cleaner for longer
Advanced Formula Motor Flush has been specifically formulated to combat the effects that extended oil drain periods and modern driving habits have on today's technically sophisticated engines. Urban cycle and start/stop driving patterns increase the rate at which acid builds up leading to accelerated and premature engine wear. Excessive lacquer and varnish formation reduces the efficiency of oil system components such as VVT systems, piston rings and Hydraulic Valve Lifters."

Thanks for the response.
Could be worthless, although not damaging.
Might save a tenner and buy a few beers instead.
Was just wondering....

[creepy coupe]

Save your money, with 40k on a engine running fully synthetic oil, you will be fine.

[Oli]

Forte flushes are the best, and work really well. We sell them, approx 12 pounds. You put them in and run the engine for approx 20 mins, when you drop the oil, and refill you'll be amazed at how clean the new oil will remain. I've always used them on mine and customers cars, and highly recommend them. Go for it, you won't be disapointed. The Forte injector cleaners are superb as well.

Just my tuppence.

[MEGA]

Is it worth adding flush but then not changing the oil? lol

[Oli]

Er..........no!

[Dr Dave]

Originally Posted by Oli

Forte flushes are the best, and work really well. We sell them, approx 12 pounds. You put them in and run the engine for approx 20 mins, when you drop the oil, and refill you'll be amazed at how clean the new oil will remain. I've always used them on mine and customers cars, and highly recommend them. Go for it, you won't be disapointed. The Forte injector cleaners are superb as well.

Just my tuppence.

I will echo Oli's statement - Forte is top-notch stuff.

But would I use it in a 40,000 mile car? Nah.

[Oli]

Should be used on every car, no matter what mileage, it ensures all the crap comes out at each oil change.

[Dr Dave]

Oli - are you a Forte sales rep by any chance?

[doughboy]

I'm always relucant about shifting any 'crap' in a turbocharged engine.

Even a tiny particle dislodged or 'shifted' in an oil way could get pumped through to the turbo bearings and quickly munch the said bearings. The

Hopefully my 8K oil changes from new with full ester synthetic oil will avoid 'crap' in the first place

[creepy coupe]

I think any potential crud in an engine stuck to components, is better off staying where it is, flushing oils hold muck in suspension which then get sucked through the oil pumps strainer, then through the pump and finally into the filter, any larger particles can stay in the strainer and impede flow in the future.

As said before, modern synthetic oils, especially for diesels have strong detergents in them, which tends to keep things in reasonable condition.

[Oli]

Using the terms 'think' and 'reasonable' suggests your answer is more guesswork and Internet trawling, than actual knowledge?!. We service 6 plus cars a day, and I can confirm 100% that the forte flushes work and clean the internals of the engine, for smoother running, reduced emmissions and better mpg. I have always used them on everyone of my cars, be it the 1st or 10th service.

I am not trying to sell them here, but just point out their usefulness

[Oli]

Originally Posted by Dr Dave

Oli - are you a Forte sales rep by any chance?

No I run my own independant garage and have been involved with forte for approx 15 years or so.

[Dr Dave]

Originally Posted by Oli

No I run my own independant garage and have been involved with forte for approx 15 years or so.

Good, because I was in a similar postion until I decided I'd had enough of the trade 4 yrs ago - Forte is a great product both in diesel/gas treatments and the oil flushes and I will continue to endorse them!

Never failed to get a diesel through the emission test with a filter full of Forte Diesel system clean! Brilliant stuff.