2001 740i won't fire

[Beemerphan]

Beemerphan said:
Today 07:03 PM
Hey everybody. I'm brand new to this site/forum, AND to BMW ownership. I REALLY hope someone can help me, as I have a very frustrating issue I need help with (PLEASE!). I recently bought a 2001 740i (4.4L w/ dual overhead cams) that cranks, but won't fire. Previous owner claims it simply died while being driven. After hooking up a "generic" hand-held diagnostic computer/code reader, a reading at the cam sensor was indicated. The assumption was that the sensors themselves were bad, but after replacing those AND installing a new battery, he realized the timing chain guides had failed. He then replaced those and re-set the cam positions/timing with the # 1 cylinder at top dead center. So everything should be good to go now, right? Wrong. As stated, it cranks but still won't fire. Is there some kind of safety reset button? I'm thinking maybe when the timing chain guides failed there was a safety feature that disabled the engine to prevent further damage (?). Any ideas or suggestions? Thanx, Sean

[Sundaycruzer]

Crank sensor possibly, but setting a vanos motor requires more than 1-4 cam being set to tdc. There's a hole procedure and tools required. I've done 3-4 and it's time consuming and if you get it wrong you will be buying another motor. If he did the vanos right you should find someone with a better scanner to check codes


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[Beemerphan]

Thank you VERY MUCH for responding. I failed to mention that hole in flywheel was also aligned at the bottom. But what else could getting it wrong, as you mentioned, entail?

[Sundaycruzer]

This is how it's done, plus rebuilding the vanos itself. Easiest way to describe procedures
http://beisansystems.com/procedures/m62tu_vanos_procedure.htm


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