BMW E38 740iA -95 runs only few cylinders

[Caghot]

Hi.

New in here, so apologies if placed this thread in wrong place.
Anyway.. Now i have a serious problem.
Everything started about couple of months ago. When accelerating in high rpm´s about 4000 and above it was felt clearly that there was lack of power. The fauld codes gave 201 and 203, lambda integrator Bank 1 and Bank 2. Codes were cleared but nothing changed.
On tuesday when i was driving home, something very weird happened. When accelerated there was terrible shaking and vibrating and the speed didn´t increased over 60 km/h. Stopped nearest bus stop and engine stalled. Hopped out of the car and there was a bit of weird odoured smoke in the air, difficult to describe it but it was something like burning oil and plastic.
Tried to start the car, started but now it runs only few cylinders. I got it back to my yard, red fault codes and those were same. 201 and 203 Lambda integrator Bank1 and Bank2. For a couple of days tried to solve the problem with help of Finnish BTCF forum but nothing seems to help.
What i´ve done so far is unplugged both lambdas, inspected vacuum leaks, isnpected coils and plugs, unplugged MAF (idle changes when plugging). But no, car starts pretty well but immediately it starts to run with few cylinders.
Noticed couple things when did inspections. Half of the plugs were carbon foulded, when unplug camshaft sensor nothing happens no even fault code, when unplug crankshaft sensor engine stops running and gives a code, found a burnt 40A fuse near DME (replaced, no effect).

So.. Does anyone have a clue what this might be?? :D I´m running out of ideas. Haven´t been on school couple of days because of this and next week i should go back to work, so would definitely need immediate help with this.

[Timm]

It sounds like one of your catalytic converters is blocked (or both). Get under the car and give the cats a hefty clout and see if they rattle (the tell-tale signs of a disintegrated catalytic element). If one is blocked you will get plugs that differ in colour one bank to the other....

[Caghot]

I tried earlier take oxygen sensors away from exhaust pipe but those were so tight that couldn´t get them out. But i knocked pipes with wrench and before oxygen sensors the sound was "crystal clear" like it should be in empty pipe but after sensors the sound was very different.. Like there was no echo at all.
And now the problem is that i should get the car towed to lifter so i could remove the exhaust pipes from headers and test if it starts to work.
Or do you have some hints could this be done without lifter?

[nah2323]

maybe some sort of wildlife crawled in your pipe and is blocking something up. Taking out the O2 sensors (lambda) will improve the condition if your exhaust is plugged futher away from the engine.

You can also separate the pipe as far forward as you can and see if that helps. Usually this is a bit tougher as the bolts can be quite rusty.

Goodluck!

[Caghot]

Thanks to both of you for reply.
Now it´s snowing and winding so bad that no way i´m gonna get out there to remove the exhaust pipe. :D But as soon as i have the job done, i will post the results here so if there´s someone else who is struggling with this same problem may find help too.

[Edwin NL]

Did you pull codes?

[Caghot]

Yes i red the codes and now there was something weird. There were codes from DME:Throttle valve potentiometer, AGS:Electric pressure controller and CAN Gas pedal position.
Never been there before.. I ended up to charge battery to full and connected car´s + and - conductors together with turning the key to acc- position, so all weird stuff should be cleared after this.

Now the car runs idle speed only about 400-500 rpm and if you press accelerator pedal feels like engines chokes, when start to pump the pedal you can keep it running.
I can hear some metallic sound while engine running, not sure if it comes from cats or where. Very difficult to locate. Also noticed that at the end of exhaust pipe (both of them) comes smoke. From drivers side comes more than passengers side. And you can say from the smell of exhaust gas that there is a lot of unburnt fuel..
I´m really getting tired of this.. :D If quick solution is not found maybe i give up and buy an opel. :devillook

[kakocemo]

Ignition coils,spark plugs as you mentioned lots unburnt fuel.

[Caghot]

Ignition coils,spark plugs as you mentioned lots unburnt fuel.

Hi.

I measured the coils and resistance between pins 1-3 were 0,6 ohms on each one of them.. Should be ok? And should INPA give some misfire codes if detects a faulty coil? Also plugs are changed about month ago so i´m gonna change them again if nothing else seems to help.
I´m gonna measure camshaft- and crankshaft sensors with oscilloscope and see if theres some problems.Cause the resistances between 1-2 pins were Camshaft:1,2 kohms ahd Crankshaft: 420 ohms and in my suggest those are similar sensors and should give about the same resistance reading between 1-2 pins.

[Edwin NL]

Cats clogged?

[Caghot]

Cats clogged?

Yes.. Cats glogged.Drilled 6 mm holes through cat and car started to run with all cylinders.
So i´m gonna take the parts away from inside the cats and weld those back.
Thanks to all of you very much from answers!!! :buttrock