Black smoke when accelerating/ revving

deltasierra · Post by **deltasierra** » Mon Nov 20, 2023 8:15 am

colb wrote: ↑Sun Nov 19, 2023 9:05 pm Ignore the oil level sensor they are a regular fail, it won't affect the running engine just set a code. Of your sure it's fuel related then view fuel trims in love data to see what it's doing. High fuel trims often caused by vaccum leaks from holes or splits in intake boots and hoses across the engine. Smoke test will find any that can't be found on a visual check If the smoke when running is black and oily then you might be looking at worn piston rings and bores andaybe valve guides. The latter is the cause of oily smoke on the overun as the engine slows down worn guides will allow oil Tobe sucked down the guides and get burnt in the cylinders.

The OP refers to a “thermal oil sensor” is this the oil level sensor and there is no oil “temperature” sensor

Zowen · Post by **Zowen** » Mon Nov 20, 2023 10:43 am

Hi Ive found the problem! fuel injectors leaky and they shoot fuel everywhere! 2 fuel injectors where faulty and I want to check the pump as well. I havent fixed it yet so don't know 100% if this will solve the problem but Id imagine so.

Zowen · Post by **Zowen** » Mon Nov 20, 2023 10:45 am

deltasierra wrote: ↑Mon Nov 20, 2023 8:15 am The OP refers to a “thermal oil sensor” is this the oil level sensor and there is no oil “temperature” sensor

Sorry yes I ment oil level sensor, reading off a poorly translated german OBD reader

enuff_zed · Post by **enuff_zed** » Mon Nov 20, 2023 10:50 am

Zowen wrote: ↑Mon Nov 20, 2023 10:43 am Hi Ive found the problem! fuel injectors leaky and they shoot fuel everywhere! 2 fuel injectors where faulty and I want to check the pump as well. I havent fixed it yet so don't know 100% if this will solve the problem but Id imagine so.

Sounds like that's your problem.
Think I'd be tempted to change all of the injectors if you can afford to.
Don't worry about the pump just yet.

Zowen · Post by **Zowen** » Mon Nov 20, 2023 11:15 am

enuff_zed wrote: ↑Mon Nov 20, 2023 10:50 am
Zowen wrote: ↑Mon Nov 20, 2023 10:43 am Hi Ive found the problem! fuel injectors leaky and they shoot fuel everywhere! 2 fuel injectors where faulty and I want to check the pump as well. I havent fixed it yet so don't know 100% if this will solve the problem but Id imagine so.
Sounds like that's your problem.
Think I'd be tempted to change all of the injectors if you can afford to.
Don't worry about the pump just yet.

Was planning on it if 2 are faulty im assuming there both quite old so I'll change all of them and keep the 4 none leaky after i check the resistance just incase.
Do you reccomend any fuel injectors?

enuff_zed · Post by **enuff_zed** » Mon Nov 20, 2023 12:27 pm

Zowen wrote: ↑Mon Nov 20, 2023 11:15 am
enuff_zed wrote: ↑Mon Nov 20, 2023 10:50 am
Zowen wrote: ↑Mon Nov 20, 2023 10:43 am Hi Ive found the problem! fuel injectors leaky and they shoot fuel everywhere! 2 fuel injectors where faulty and I want to check the pump as well. I havent fixed it yet so don't know 100% if this will solve the problem but Id imagine so.
Sounds like that's your problem.
Think I'd be tempted to change all of the injectors if you can afford to.
Don't worry about the pump just yet.
Was planning on it if 2 are faulty im assuming there both quite old so I'll change all of them and keep the 4 none leaky after i check the resistance just incase.
Do you reccomend any fuel injectors?

Not had to change any myself, so no experience with the various makes, sorry.

colb · Post by **colb** » Tue Nov 21, 2023 11:33 am

BMW TIS Injector removal Z4 2.5
https://onedrive.live.com/?cid=93F57B94 ... 05&o=OneUp

x-driver · Post by **x-driver** » Tue Nov 21, 2023 9:45 pm

Take out O2 sensors, visual check them, find out if they are aftermarket (might not work right), at that point you can also check your cats through sensor holes with a special camera.

What is your fuel consumption?

Also try to unplug MAF sensor and try to drive and see if there is any difference. Usually it gets better if MAF is bad. With the sensor unplugged the engine will run on some precalculated values. This (bad MAF giving false values) might also not throw a code.

As others said, check for vacuum leaks as well. Although this should throw a code if there was any leak.

Zowen · Post by **Zowen** » Tue Nov 21, 2023 10:21 pm

x-driver wrote: ↑Tue Nov 21, 2023 9:45 pm What is your fuel consumption?

Im getting about 35mpg overall with mix driving styles

x-driver · Post by **x-driver** » Tue Nov 21, 2023 11:01 pm

Had to convert this into L/100km which I'm more familiar with and found out it's unbelievably low consumption. Are you sure about this?

Argyll Andy · Post by **Argyll Andy** » Tue Nov 21, 2023 11:05 pm

x-driver wrote: ↑Tue Nov 21, 2023 11:01 pm Had to convert this into L/100km which I'm more familiar with and found out it's unbelievably low consumption. Are you sure about this?

Many, many people on here would be delighted with 35 mpg - I’ve not had anything close in any of my Zeds. Last group run out we had we were all averaging under 20 mpg

x-driver · Post by **x-driver** » Wed Nov 22, 2023 12:12 am

I'm having cca 25 mpg and I think it's pretty good

I'm used to 19-21 mpg with my e39 530iA... 35 mpg seems unreachable for 3.0i M54 engine.

Zowen · Post by **Zowen** » Wed Nov 22, 2023 12:27 am

x-driver wrote: ↑Wed Nov 22, 2023 12:12 am I'm having cca 25 mpg and I think it's pretty good I'm used to 19-21 mpg with my e39 530iA... 35 mpg seems unreachable for 3.0i M54 engine.

Uhm the attached photo was a 90 mile trip down the motorway driving sensibly, I reset it before the trip. ive been getting around 400 miles a tank? See I could probably always get good mileage but then whats the point in the car?

x-driver · Post by **x-driver** » Wed Nov 22, 2023 1:53 am

I kept that in mind of course

I was always talking about average consumption, not the best possible with careful driving.

Zowen · Post by **Zowen** » Wed Nov 22, 2023 3:27 am

x-driver wrote: ↑Wed Nov 22, 2023 1:53 am I kept that in mind of course I was always talking about average consumption, not the best possible with careful driving.

530i will be much heavier though got to remember z4 weighs next to nothing even ragging it everywhere I think I'd get 20mpg haha

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