BMW 120i power loss

[Aprilia99]

guys, pregressive power loss on a low miles 2005 120i.

struggling to start now. would just weeez out and die.

presume its the timing chain.

couple of garages said they wont touch it, as there can be multiple other issues, im not sure im happy to pay about 1k to get it sorted for it to have more issues, anyone have experience on this, car is based in oxford.

thanks

[Craikeybaby]

I had a vanos issue on mine, but that threw a warning light. Whilst they had the engine open I had the timing chain replaced as it looked stretched and it has been running brilliantly since. It cost £1,100 at a BMW specialist, including a few other bits.

[Aprilia99]

thanks, which specialist?

[Craikeybaby]

Autotech in Warwick. Their details are in the BMW specialist wiki at the top of the forum.

[iSore]

Mark Purcell in Oxford is your man.

2005 means it's the N46 which whilst a fairly poor engine, is not the utter disaster that the 2007 onwards N43 is. With the N46, step one is diagnostics and fault codes. Most of these need a chain and guides which if the guides are still intact, can be done with the sump on. A good opportunity to replace the many leaking oil seals and gaskets as well. Could be a lot of things - vanos units, Valvetronic motor or sensor, crank or cam sensors, vanos solenoids.

I have a box full of used N46 bits from various repair jobs on these things. Don't buy new bits if you can avoid it - except the crank sensor. Genuine BMW only!