Thread: Running issues, one for the gurus

Marty
Have you had the codes read ?
I would check inlet and exhaust manifolds for leaks and replace the fuel filter in the first instance. If no better then may be looking at probably the camshaft position sensor codes read. Just my 2 cents
Laurie

Hi Laurie,
I did have the codes read and that came back with a misfire on cylinders 1,2 & 7, I think intermittent was mentioned somewhere, so I changed out the supposedly duff ignition coil packs with some spares, this didn't make any difference, if anything things did seem to get a tad worse. Fuel filter is on the list I have one I just have to fit it. I have also ordered a fuel system pressure checking tool off Fleabay so I can actually watch the pressure as I start the engine, see if that gives me any clues.

I fitted new plugs however they weren't the "top of the wozza", they were the cheaper grade, maybe the engine likes expensive stuff, wouldn't surprise me. Saying that the engine had the same symptoms with the old plugs in which were the double platinum plugs, one reason I started on this quest to figure out what was going on.

Because the issue comes and goes I had discounted the inlet manifold, I would have expected that issue to show itself all the time and not at just random times if this was a crack or a dodgy inlet manifold gasket. Not so sure about this one now.

Thanks for the suggestions, definitely something else to consider.

G`day ,

have you compression tested it , being the way BMW do it that 1 & 2 are side by side same bank .

The missing you give 1,2,7 must be very pronounced i`d think as firing is 7,2,1 which give 3 cylinders in order missing or is this oversimplifying .

What were the old plugs saying as far a colour etc .


Haven`t gone through it but could have some ideas

General diagnostic procedure for a single or multi-cylinder E39 intermittent misfire? - Bimmerfest - BMW Forums

We are talking about a 14 year old engine here, How many K's on this engine?
Fitting the incorrect spark plugs is pretty much a waste of money, What is the condition of the plug leads?
Is the engine loosing any coolant, oil and does it blow any smoke from the exhaust?
As was stated above a compression test is a Great idea.
Maybe the hydraulic lifters ( If fitted in this engine) are on their way out as well.

Hi There,
So the engine has 202,000 klms on it so I wouldn't put it down as worn out as yet. Compression test, now there is a good suggestion, the vehicle is unregistered so i haven't been able to do much running around to prove or disprove a lot of ideas and or theories. I'll have a look at the plugs when I do the compression test, at this time there is no excess pressure or signs of bubbling in the overflow tank so I was discounting a blown head gasket at this time.

I have had a suggestion of the TPS being faulty or possibly a tired fuel pump as well, so right now I have a developing list of things to check. As and when I get things checked I will feed back, thank you all for your constructive feed back and things to check, appreciated.

Cheers Marty

Vanos, or camshaft position sensor?

Hi Rar110,
Well until about 20 minutes ago you had me at VANOS.......... after a bit of a Google and a few home videos I am a lot wiser, the symptoms described by others seem to fit with where I am right now. Also considering the underside of the rocker cover when I replaced the gaskets this cause seems ever so more likely. Thank you for this, should be something quite easy to get access to and check / clean.

Cheers Marty

So what’s the likely problem Marty?