Hi I'm considering buying a very nice 2005 525i with full service history the car looks faultless but has 166000 miles the engine is unmodified will it need an engine rebuild soon or keep going years
Hard to say. Most BMW engines will last to 200K with normal oil changes. It's a crap shoot buying a used car. I like to buy one owner vehicles with a good history and under 100K.
If the bmw has been well maintained and in as great of condition as you say it could go for a very long time. Most bmw engines don't need to be replaced unless the oil has not been changed regularly. One thing you can check is too see if the oil is gummy. Look under the oil cover and if its very cakey looking good be that it was not change regularly. Also any nocking or ticking noises can indicate an engine problem. Hope this helps
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