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SE to ST/engine swap

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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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Only one choice, put the same type engine back in if you need to use the car anytime soon.

No-one has done an ST swap yet, as at best guess you need EVERYTHING from an ST to do it. Drivetrain complete, shifter & pedals, engine electronics/wiring, maybe even the suspension to fit the ST drive shafts.

If you've got a wrecked ST on hand, and a year to fiddle with it, go right ahead.
 

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w/ my magic bag
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33,477 Posts
Only one choice, put the same type engine back in if you need to use the car anytime soon.

No-one has done an ST swap yet, as at best guess you need EVERYTHING from an ST to do it. Drivetrain complete, shifter & pedals, engine electronics/wiring, maybe even the suspension to fit the ST drive shafts.

If you've got a wrecked ST on hand, and a year to fiddle with it, go right ahead.
Reallisticly you'd want to install a similar engine back in. Like Sailor mentioned a lot of work + the time/labor & money.
 

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6 Posts
Discussion Starter · #6 ·
Reallisticly you'd want to install a similar engine back in. Like Sailor mentioned a lot of work + the time/labor & money.
Actually, I can drive around in my Suburban meanwhile. I'm just eager to get back into my car but if this build does go through it will definitely be worth the wait. The labor would be at little to no cost actually. I have a mechanic who's expertise is engine swaps.
 

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2 Posts
Only one choice, put the same type engine back in if you need to use the car anytime soon.

No-one has done an ST swap yet, as at best guess you need EVERYTHING from an ST to do it. Drivetrain complete, shifter & pedals, engine electronics/wiring, maybe even the suspension to fit the ST drive shafts.

If you've got a wrecked ST on hand, and a year to fiddle with it, go right ahead.
I'm there too zx5 about to die even If I want to go with full engine trans ecu wiring struts hubs but once there will the hub fit with the arms balljoin of the zx5 and if not will the arms of the st fit on the zx5 ...
 
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