I think PaulB just hadn't noticed the year and thought it was the later 4.4 diesel - which does have a turbo - or rather two turbo's.

Sorry Paul, I was taking the p*** a bit, but didn't mean to appear a tw@.

It is of course a BMW 4.4 litre petrol V8 - normally aspirated. Hope it gets sorted.

Hi everyone, here are some more details:

It affects the left bank n/s
The spark plug in cylinder No 3 was alway wet with petrol.
Two coil pack were changed
All the spark plug have been changed.
The MAF has been changed.
The PCV unit & hoses have all been changed
Auto Electrician has checked the ECU and the feed to the coil packs, all ok with good sparks.

After rebuild by Engine Engineering. It still has the same problem although the affected cylinder is now No 1
with a compression reading of 90 the rest have between 130-135. We have put this down to lack of lubrication due to the amount of unburnt fuel in the cylinder.

We think the injectors may have swapped places during the rebuild hence the change of affected cylinder

I will be cleaning the injectors tomorrow after this I will have no idea.

If there is unburnt fuel in the cylinder that will provide plenty lubrication. Sounds like a valve is not seating if compression is down on a rebuilt engine..
Also.. If the plug is always wet it sounds like the injector is doing its job, it's just not sparking.. Or do you believe there is so much fuel being injected it is flooding? Previously..
Vogue SE TD6
Defender 90 2.4
Defender 110 TD5
Vogue 3.5 EFI

The auto electrician said all the coil packs & plug are sparking ok. So I appears to be killing the spark and misfiring due to a faulty injector flooding the cylinder and the excess spits out the exhaust along with all the smoke.

if you are talking white smoke, that sounds like oil and water together so people think head gasket. if you uncouple the bad injector, yes you will throw a code, but you wont allow fuel in that bore. and if no spark it will clear itself a lot. what will the smoke be like then I wonder. perhaps the injector did move to 3, but it might be staying open electrically, or seized. removing injector pluf to that bore will shu it down.. sort of if you can get a similar fitting injector, or direct wire an odd shaped one, from harness the injector and have it in your hand while engine runs, that will tell you if its clicking.

the only thing is, you talk of poor compression on one bore....is that the 'old' number one or 'new' number three. changing injector and still same means a call to engine builders!

I wonder if you have two separate faults. white smoke from an ill fitted new PCV valve, and a misfire. I think a pcv valve will smoke through inlet manifold, through both banks, and down both exhausts, a bad bore on one bank will smoke down one. but the exhaust backbox will mix them. if you remove backbox, and start it, first rev it up to hear that lovely raw v8 sound....... and then check the smoke from each. maybe duct it away with some cardboard carpet tubing to separate it properly, don't get under it while running you will gas yourself. neighbors will think you are adding a boyracer exhaust! but checks like these are free to do sort of.

water levels ok? confirmed?


PS you are risking your cat(s) whilst running unburnt fuel through engine.

Before the engine went away the problem was no3 cylinder misfiring and flooding.

That problem appears to be at no 1 cylinder now

That is why we carried out a compression test. I'm hoping the compression will increase if we can get it to fire up correctly as this will allow the rings to expand and lubricate as they should.

Yep, wrongly presumed it was a diesel.

I will get my coat.

Compression tests are carried out cold. There should be no reason a newly rebuilt engine should have such a significant compression reading difference on one cylinder. Previously..
Vogue SE TD6
Defender 90 2.4
Defender 110 TD5
Vogue 3.5 EFI

so if you were to take off the affected no1 coilpack, or use a substitute, and couple it to the multiplug connector, you will have a free hanging coilpack, that is in circuit. put in a spark plug and earth the plug body well. and when its dark, run engine to see sparking plug. proving a spark. if it strong it will be blue, white, not so strong. if good refit multi to engine recheck. maybe wrestle wires a bit. (it low tension, so safe) could be bad until wrestled, and shows good when tested by electrician.

Would the engine builders have taken test results before it was shipped to me?

I would have thought so... Surely as part of a quality control check. Contact them and tell them there is a significant compression difference in one cylinder. Previously..
Vogue SE TD6
Defender 90 2.4
Defender 110 TD5
Vogue 3.5 EFI

I will give them a call in the morning

If you disconnect the wiring to the injector, so it gets no fuel and start it up, I wonder if it will still smoke...? Previously..
Vogue SE TD6
Defender 90 2.4
Defender 110 TD5
Vogue 3.5 EFI

I will try that test also