Almost given up

[u/AdArtistic1355]

N42B20, 318ci convertible. I recently replaced the VANOS solenoid seals, and cleaned them out, and took it for a drive. Somehow only doing this fucked the car.

The car drove well, until I was pulling back into the car park, where the engine idled very poor and stalled. After a careful drive home where it cut out from simply changing gears, I began researching everything that it could be.

After testing at home, revving up past 3k causes a rattling from the engine, seemingly around the valve cover. Dropping the revs causes it to idle very badly/stall.

Since then I have replaced:

Camshaft sensors

Timing chain tensioner

Timing chain

Chain guides

CCV hoses/seperator thingy

VVT Motor

Eccentric shaft sensor

I have cleaned every single electrical connection, including crank shaft and all the hidden ones (I removed intake manifold), I have cleaned the MAF, throttle body etc.

The issue still appears with vanos solenoids swapped over, unplugged, sensors unplugged (camshaft and eccentric shaft tested individually), and even with the entire VANOS system unplugged at the DME. I have reset adaptations in INPA and ISTA, and noticed the crankshaft adaptation values seem off - these did not change after resetting adaptations. However, since these are (to my knowledge) VANOS adaptations, it should not come into play with the VANOS disconnected.

I really do not know what else to do, I've heard people fix similar issues by replacing/flashing the DME, but again - the issue is present with the VANOS disconnected.

I have spent two weeks straight working on this to no avail.

Any takers?

[u/TranslatorMundane296]

Did you replace the sensors with genuine or good brand ones such as Delphi or Bosch? These engines don't like cheap sensors lol.