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SE to ST/engine swap

33316 Views 11 Replies 7 Participants Last post by  Thiboutot
Okay so unfortunately the motor in my NA MK3 sedan is no good. I was out two nights ago when all of a sudden I heard a slight knocking noise coming from my engine bay. I parked the car but didn't think too much of it. A few minutes passed and I came back to the car. I turned it on, heard a much louder consistent knocking sound and my CEL light came on. I had engine knock. I had to drive the car home, and the whole time the throttle response was VERY weak and the knocking remained throughout the whole ride. I was scared to push it past 30 mph.

The next morning I went out and decided to do an oil change on it hoping it would take care of the knocking. Only one quart of oil came out when there should have been five. It had only been 2000 miles since the last oil change and I could not see leaks anywhere, everything was secured tightly. Next I checked the spark plugs. One of them was completely fried. The center electrode and ground electrode had merged together and there was no gap in between.

I had a mechanic come look at it and he determined that the engine was done for. He said I would need a new engine.

I've always admired the Focus ST so this leads me to the main question. How do I get a Focus ST engine in my NA MK3 sedan? Also, my sedan is automatic so I would need a manual transmission. What sorts of modification will I need to get the motor and tranny hooked up properly? It seems that the main problem will be with getting the ECU to work properly, at least judging from other posts with the same idea. This is also something that would have to be completed as soon as possible seeing as to how it was my daily driver. The old motor is already getting yanked out today. If anyone has any info, help, input, or anything on this build, it would be greatly appreciated. I'll make sure to keep you guys updated. Thanks.
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I assume it's out of drivetrain warrenty?
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