E36 Sudden Loss Of Power

Hello, I wonder if anyone can shed some light on this little problem my car had yesterday. The AA man had to toe me away. I was driving my 318i up a hill doing 30mph but it seemed like it wasn't as powerful the engine was warm by now too. I came to the junction and it ticked over ok, then I booted it to overtake, bout 4000rpm and I heard a backfire and it cut out.

I the AA man came, did some checks in the fuse box with his test equipment, turned it over a few times, fuel was there etc. But he said it seemed like it was firing at the wrong time. Could be a CAM or CRANK sensor. I was toed to my local Bosch specialist and they said the same thing.

I've never had anything go wrong with this until now, does anyone else agree? Or had this before? All thoughts on the matter greatly appreciated.

Ok, its been to my local Bosch specialist, they couldn't get the diagnostics to communicate. they said they were almost certain it was the carnk or cam sensor. They changed em and it still wouln't start. So they arnt chargin for fitting the sensors, they are sending them back. They are getting some guy with a BMW ECU interrogater to find out whats the problem. Anyone got any ideas? I'm getting worried now. Thought it was something simple. I hope its not the ECU. I was under the impression it could only be airflow meter, oxygen sensor and idle/throttle valve. But I think if any of these goes it has got a limp home factory default value.

Someone please shed some light, to prevent me crying when they ring with some bad news.

cheers

Brendan

Well 4 days later and £399.97 shorter and we've cracked it. We had the BMW diagnostics on it today. There were zero amount of fault codes stored in the ECU and everything was running ok according to that!

So they gave a quick call to a BMW specialist in Tamworth, they cracked it! Without looking they said check the dual mass flywheel that comes off the cranck. 80% of E36 M43 engines have this problem at some point in their life. There is a woodrough key in the drive for the flywheel. This broke but the bolt that holds it tight against the shaft, held the timing or dual mass flywheel in place. Then when the engine was above idling throttle, the flywheel slipped, giving a false reading from the Crank shaft sensor.

So they stripped it all down, changed the key, tightened the chain etc checked the water pump etc and hey presto!

Its running like a babe. Its so responsive and sounds beautiful. They said the nut was that tight  could have been holding like it for a while. Anyhow i'm so happy now and so are my credit card company. Thanks everyone that gave an input.

See you all at Mallory on Sunday.

No its not the Gearbox flywheel, its the dual mass one. Its hard to explain in words. the flywheel at the front of the engine that sits in front of the timing chain gear. Its got a pulley that drives all the accessories like power steering and alternator etc. The crank sensors reads off that. had to take the timing cover off, timing chain water pump etc to get to the slot where the key fits.

Zim Zimmer wrote: No its not the Gearbox flywheel, its the dual mass one. Its hard to explain in words. the flywheel at the front of the engine that sits in front of the timing chain gear. Its got a pulley that drives all the accessories like power steering and alternator etc. The crank sensors reads off that. had to take the timing cover off, timing chain water pump etc to get to the slot where the key fits.

Oh, the crank pulley. There is a vibration damper mounted on it. The dual mass terminology usually refers to the main flywheel where it is made up of two parts.