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George H.
George H., ASE Certified Technician
Category: Car
Satisfied Customers: 18592
Experience:  ASE Master Tech 15+ yrs, AAS Automotive Technology, Factory trained Asian specialist
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hyundai elantra: my mechanic has mounted the new 03..bypass

Resolved Question:

I just bought a used 04 hyundai elantra engine, and my mechanic has mounted the new engine onto my 03 Elantra.. He calls me and tells me that the engine won't start because these new engine has an ocv by the engine head that the old engine didn't have??? I'm lost here.. your help would be greatly appreciated. I'm sure there should be a way to bypass this add on valve or something.. thanks..
Submitted: 8 years ago.
Category: Car
Expert:  George H. replied 8 years ago.

Hello I will answer your question,


The OCV is the oil control valve which is mounted to the end of the camshaft and allows the camshaft to be rotated slightly to changr the valve timing for more power and betteer fuel mileage. The engine should start but will not run properly with this setup so I suspect that something else is inhibiting the engine from starting.


Why was the engine replaced? Did it overheat?

Customer: replied 8 years ago.
Hi George, yes the engine overheated and was a mess. so we decided to buy an engine from a junkyard and just start fresh. are you saying there is no way of gettin this 04 engine to work on my 03 elantra GT? I can't believe an 04 and 03 engine would be that different.. thanks so much.
Expert:  George H. replied 8 years ago.

Yes there was a major redesign in the head to meet emissin standards. If you replace the head with an 03 it will work with the short block but you may be better off trading the engine for the correct year as it is most likely more expensive replacing the head.


Sorry for the bad news but give your mechanic this website:


It is free to use and will give him access to factory level information.


If I have answered all your questions please ACCEPT this answer so that I may be paid


Thank you



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