Does anyone know if an e36 318i engine will fit in a e46 318i??
In theory, yes. Engine management, NO. Why in the world would you want to go backward in technology, performance, and good sense? Newer is definitely better.
Should be physically possible (might need to transplant the transmission and driveshaft too) but like Michael said there's no point to do so. Electronically it would be a pig to do, the E46 is CAN whereas the E36 is old style OBD. The car would more likely than not be unable to communicate with the engine and keep giving all sorts of errors.
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