- Blank off swirl-flap vac-hose.
- Replace EGR vac-hose with one that came with new engine.
- Check wiring to GP module. (No replacement.)
- Remove and clean EGR.
Boost was lacking and noisy again so I figured there was more vacuum-leak. Assuming the redundant swirl-flap diaphragm was to blame I set about removing that hose completely from the servo-hose T-piece and fitting a blank stopper from the new engine. While doing this I found the vac-hose to the EGR was snapped off at the nozzle. Classic.
Trouble codes:
- All 6 glow-plugs no activation. Intermittent, but happened 31 times out of 40, all at the same times. I intended to swap the module for the one from my replacement engine, but couldn't find it amongst the parts so it mustn't have been included.
- [3FF0] Air mass meter failure.
- [4507] MAF controlled EGR flow too low. Both of these happened once around the same time as each other and have not happened since. Perhaps the snapped EGR vac-line could explain this.
- [4B10] Smooth running controller, correction quantity too high. This was the most intriguing of the codes as it had registered 9 times.
Smooth running controller measurement:
This measures the amount each injector has to provide each time it is fired and how much the ECU needs to meter them. The ideal correctional values are between -2.5mg and 100mg per stroke, so as you can see my measurement is indeed showing very high amounts of correction. [NOTE: The reading is in kJ, not mg as displayed! Autocom GDP just does this. I get a proper reading in this post with INPA - http://beemerlab.blogspot.co.uk/2015/07/e60-new-engine-tune-up-part-5-injectors.html]. The reasons for this are faulty injectors, lack of cylinder compression and lack of flow to the EGR. At first glance it would appear injector 5 is giving no reading as there should be a correction value there, but the engine is running on all six cylinders therefore number 5 is firing. So what gives here? I started a thread on BMW Land [BMW Land is down for now sadly :(] with some damning results on injector 5, which I will have to investigate, play with the wiring etc.
Another cause of low compression is a cracked / leaky exhaust-to-turbo manifold. This would also cause low gas flow to the EGR and stifle the amount of exhaust gas powering the turbo, explaining the boost problem. I will get someone to rev the engine as I feel round for a leak of hot gases, but if this turns out not to be the case then the only things left to do will be replace the waste-gate and/or pressure-convverter.
- Check for pressure leak from exhaust-manifold.
- Add injector cleaner and cataclean.
- Investigate boost actuator / pressure converter and waste-gate.
