[haidentann]

Anyone experienced this on an N43 engine before? Currently got my 318i in the garage with this fault. They've run diagnostics but everything has come back okay. BMW tech has took rocker cover off and inspected guides, his theory was the chain guide has broken and blocked the pick up lines to the vacuum pump. Chain guide is fine though. He's found debris on the vanos solenoids and now wants to drop the sump pan to investigate further. Anybody had this fault before and manage to fix?

[Andystobbs]

The vacuum pump is on the back of the head. Its not in the sump (although it is on a diesel). Have they analysed brake vacuum available? If the car has stop start there will be a vacuum sensor on the servo which they could use to read data from, or alternatively connect a gauge in the time honoured method. Under what conditions are you seeing this warning? Does your garage have fully featured diagnostic equipment?

[haidentann]

Thanks for the reply Andy. It's at the BMW main dealership in Blackpool. They've run diagnostics and said the vacuum pump is absolutely fine. They've also inspected timing chain guides and checked the oil pickups from the sump are clear. Which they are. Now they want another 300quid to adjust the timing which they have no reason to believe is out. Absolutely nightmare. Think I'm going to pick the car up and start diagnosing myself. I know my way around a car so not afraid to try any suggestions people may have, providing it doesn't require the engine removing or car putting in the air.

[haidentann]

Also the light comes on as soon as I switch the ignition on pretty much. Car drives fine although has brought up the odd camshaft position sensor fault at the same time

[Andystobbs]

Adjust the timing sounds interesting. Especially at £300 for two bolts.
I agree. Pick it up and spend some time on it yourself.

[haidentann]

That's what I said. Especially when the rocker cover is already off ��. They've ran diagnostics and everything's come back fine. They've inspected the chain and guides and everything looks fine. Yet there still set on going after the timing. They took the rocker cover off without my consent and i refused to pay for it. So I think there trying to make there money back on that by overcharging me on a timing check. I'll be picking it up and looking for oil leaks I think

[Andystobbs]

I've never come across that fault so at a loss to work out what conditions would set it off.
Also can't make sense of how the guy posting in the other thread solved it with an oil filter gasket change.

[haidentann]

No me neither. I've given up trying to make sense of N43 engine faults though. In my experience the solution is very rarely linked to the diagnostic ha!

[N5GKP]

Any chance you've had the Brake Vacuum recall / QE carried out recently? That fault is consistent with the MSA: Brake Vacuum sensor crapping itself, I've replaced a stupid amount of these sensors recently!

[therealdb1]

Originally Posted by Andystobbs

Also can't make sense of how the guy posting in the other thread solved it with an oil filter gasket change.

Wasn't that a cure for the static oil pressure fault that he had as well as the brake loading fault?

I think I would collect my car asap if I were you and look for an independent specialist that has good experience with 4 pot E90's.

Chances are technicians at a franchised stealer might have only been trained on newer models and they are second guessing the problem at your expense.

N5GKP seems to have a plausible suggestion.

[haidentann]

Confirmed by BMW that the QE recall was done in 2017. They want to adjust the timing as the car was in the garage 3 months ago for a CPS fault. The garage said the timing was out and adjusted it which cleared the CPS code. Now BMW seem to think it needs putting back. Not sure how they've come to this conclusion but I've totally lost confidence with them. I'll be collecting the car Friday and not paying any more money. 500quid down and still no diagnosis.

[haidentann]

N5GKP what's MSA?

[haidentann]

BTW, start stop has been intermittent. If this is linked at all?

[Andystobbs]

MSA is motor stopp automatik. It is the stop start system. I think your brake vacuum sensor would be an excellent starting point.

[N5GKP]

The stop/start being intermittent could be a sign something on that side of things has a fault (although there is a ridiculous amount of prerequisites for the stop start to work).

In my experience, StopStart not working, Red EML, Brake load warning point to something on the Brake Vacuum side of things.
Most common component I've replaced has been the sensor (BMW will charge you roughly 2 hours for replacement of this sensor, it can be (with a bit of fiddling and a few swear words) done in about 20mins with a level bar and screwdriver.
Next component that usually faults from there is the vacuum pump itself which is driven by the camshaft (attaches to the rear of the head). If by any chance your vacuum pump has given up I do have a spare brand new one in my tool box id let go for a very reasonable price.

But let me know how you get on, if you need wiring diagrams or any specific information feel free to give me a nudge.

[haidentann]

Thanks for the info guys! Just a little update. Contacted BMW today, they said my timing is that far out they can't get the locking tool on. Find this quite bizarre as the engine is running absolutely fine. They offered to correct at the price of £300. Tol them to go +#-) /* themselves haha! I'll be collecting the car on Friday and checking the timing myself. Followed by an inspection of all the pipes etc. To make sure there's no leaks. Failing that I'll bang a new sensor on the vacuum pump. Is it correct that there is 2 sensors? Which one should I be going after?

[N5GKP]

Timing is a weird one - I'm currently working on a 530d police car with a N57 in it and the timing is 45• out and I can't get the kit on it so that needs engine out, head off, etc - that's another story though!

With regards to the sensor, it's the one sat down under the master cylinder. Absolute prick to do, no chance you'll get your hands down there unless you have a hand that has an index finger and a thumb and a lot of palm missing!
Instructions say to remove master cylinder, etc.. I wouldn't, just use some pry bars & a ton of lubricant so you don't push the rubber grommet into the brake servo.

Best of luck!

[Andystobbs]

The cams do get out of line with chain wear. That's not surprising. Suggesting they can correct the timing without addressing root cause ie. chain wear, is surprising. That seems like a sure fire way of future problems due to inability to monitor chain wear through vanos correction factor.

The vac sensor for servo is on the servo itself.

[haidentann]

I'm starting to wonder whether the previous faults I had are related. So 6 months ago the car had a CPS fault. I put a new OEM sensor on it, belled all the wiring. Checked fuses, vanos and everything and could not fix it. I also replaced the tensioner. (the old one was about 2mm shorter due to wear) Took the car to a local indy and they said the timing was out. They corrected it and the fault disappeared. Now I am where I am with the brake loading fault and the BMW garage saying the timing is way out again?

[haidentann]

My gut feel to fix this once and for all is to bang a new chain kit on. Time up the engine and replace the vacuum sensor. For a car that's only done 45k. Seems strange it would need a new timing kit

[haidentann]

Just to close this post off. I've replaced the vacuum pressure sensor on the master cylinder and it's cleared the break loading too high fault, £130 from the main dealer. Thanks to all who assisted!