Already Driven With Petrol in a Diesel BMW 4 Series?
The engine needs switching off and keeping off as soon as you can pull in safely, if you have driven on petrol in a diesel BMW 4 Series. Spotted early, it only very rarely causes permanent harm, and sorting it out wherever you've pulled up is still something we can do.
Wherever your BMW 4 Series has ended up, Petrol in Diesel comes out to empty your fuel tank there and clean the petrol out of the fuel system. It's on fresh diesel and running by the time we go.
Petrol in a diesel 4 Series: the symptoms to watch for
A diesel 4 Series with petrol inside the tank frequently drives normally to begin with, so the signs tend to show up a couple of miles later on. With petrol or AdBlue in the fuel tank, these are the ones people usually notice:
- power drops away, especially when you ask the engine to accelerate
- it ticks over unevenly, or it runs roughly
- more smoke than usual comes from the exhaust
- warning lamps come on
- it stalls, and then may fail to restart
One of these starting after you fuelled up is reason enough to check the receipt to see what was put in.
What travelling does to wrong fuel in your BMW 4 Series
Driving is what draws wrong fuel in your BMW 4 Series out of the tank then on through your filter, your high-pressure fuel pump and your injectors. Until the motor draws it out, it stays there. The mix gets into more of the system the further the 4 Series is driven, because petrol thins the diesel that lubricates your fuel pump and the injectors on its way through them.
That is the reason to stop the moment you can rather than complete the trip. Normally, a drain and a clean are all a motor needs when it is stopped soon, because what can cause damage is travelling far on fuel that is contaminated.
It makes no difference if you have the 430d Coupe or a different version of the 4 Series.
Staying where you've stopped
You do not have to get the 4 Series anywhere. You can leave it at the side of the road or at home and we come to it, with no need to restart it and no recovery truck to book.
Somewhere safe, away from the traffic, is where to wait when you are beside a main road, with your hazard lights on.
Before you call 0333 366 0103, have your location ready, along with the mileage you drove and which 4 Series it is. Knowing the version from the badge, such as the 420d Coupe, is useful as well.
Fuel drain on your BMW 4 Series after it was driven
Compared with a drain at the forecourt, a fuel drain on your BMW 4 Series goes a step further after driving. We drain your tank first, then open up the lines and then flush them through with your fuel filter, so that no petrol is remaining between your tank and the engine. The fuel system is primed once fresh diesel has gone in, then the engine is started to check it runs correctly.
After it has run: AdBlue in a diesel BMW 4 Series
Travelling with AdBlue in a diesel BMW 4 Series usually brings warning lights, smoke and rough running, and your car might stall. AdBlue does not burn or lubricate, and it settles to the base of the fuel tank where your fuel pump picks up fuel, so it gets into your fuel line quickly. As its water dries, the urea forms crystals in the fuel lines and the filter.
AdBlue removal from a diesel BMW 4 Series after driving
The fuel lines and the fuel filter have to be cleared of the crystals after the fuel tank is drained, which is what AdBlue removal from a diesel BMW 4 Series that has been run means. Where the fuel filter needs it, we change it.
If your 4 Series has a separate AdBlue tank, that's left alone. This is about liquid in the diesel tank, not taking out or turning off the AdBlue system.
BMW 4 Series fuel tank capacity and engines
60 litres is the capacity of the diesel tank on every version of the BMW 4 Series in our figures.
There are Coupe and xDrive versions among them.
| Version | Fuel tank |
|---|---|
| BMW 420d Coupe | 60 litres |
| BMW 430d Coupe | 60 litres |
| BMW 435d xDrive Coupe | 60 litres |
What a fuel drain on the BMW 4 Series costs after a drive
How far it travelled and where it has ended up are what largely settle the price of a fuel drain on the BMW 4 Series after driving, and petrol or AdBlue makes a difference as well. Tell us those details in a call and we can tell you what is involved in the work.
Driven on petrol in a diesel BMW 4 Series: your queries
Is my 4 Series ruined?
It's very unlikely. Lasting harm is uncommon when the car is stopped early and your fuel system is drained and flushed, and that's what we do where you've stopped.
Can I make the drive home first?
It is wiser not to. Moving it is not necessary, since we can empty the 4 Series where it is. Taking it on only pushes contaminated fuel further through your fuel system.
Stalled, and it won't restart: what should I do next?
Another go draws more of that blend through with every attempt. Please leave it as it is. We get it started for you after draining and flushing it, putting fresh diesel in and priming the fuel system.
Does the version of my 4 Series make a difference?
It helps when you call if we know which of the 3 diesel versions of the 4 Series you have, and the boot badge shows it.
Is wrong fuel in my BMW 4 Series covered by my insurance?
When your car is sorted, it's worth looking at your policy, as some offer misfuelling cover. We come out whether it covers you or not.