Creativeusernam

I have a 2001 honda civic that a friend of mine blew up from lack of oil. It has the a1 motor in it. I am going to pull a motor from my local junkyard and the one that I would like to pull is an a2. What are my options? Can i just use the a1 ecu with no vtec, should i swap the heads, use the vtec with the a2 ecu (would i need to get it programmed or something?). What is the best option? I am not really looking for a power increase, I just need a running motor and the a2 is the best of the few options in the yard. Thank you for your consideration.

FRSam

Shouldn’t be hard to find another A1. Swapping just the head is actually pretty pricey once you’re all-in. It’s also pretty pointless since I’m assuming it ****ed the bottom end if you ran out of oil. If you’re strictly looking to get the car running again, go with the engine that it came with. If you want an a2, you’ll need a new wiring harness and ecu, and engine of course.

You could use the a2 with no vtec if you wanted, but I’m pretty sure it triggers some weird check engine light. Don’t quote me on that though. It’s never something I’ve done, I’ve just read about it at one point or another.

Creativeusernam

Yes an a1 replacement would be ideal but there is only 2 in my local junkyard and dont look nearly as nice as the a2 i found. When I said swap heads I meant put the a1 head on the a2 block so there would be no vtec to deal with, if that would work. And if the only other part I need to do an a2 swap is the ecu, I can easily get that from the junkyard car but i wasnt sure if i would need to program it to the new car or how much that would cost.

BrotatoChip

Check out all the info in the swap section, there are multiple threads covering the A1 to A2 swap.

https://www.civicforums.com/forums/3...c-engine-swaps

You can swap the entire A2 into your car using all your A1 parts. Without an A2 PCM though you will not have VTEC. I don't believe you will see a fault though.

FRSam

Sorry, it wasn't the vtec that caused the engine light. You need the exhaust from an A2 as well, since the layouts are different (cat is in one of the headers, I think the A1?) so the o2 sensor wires into a different spot. That's what causes the engine light to come on.

But now that I understand the head swap you were referring to, that would work fine. A2 pistons have slightly higher compression but they're identical otherwise.

Slumpertcivic

I would just use the whole A2 motor. The odds of your A1 head not being damaged while your bottom end ground itself to death seems unlikely.

The A1 ECU will not care which head you have, and the current exhaust/catalytic setup will bolt right on the A2 motor.

Same with egr system if your donor engine has it, you could just ignore it. Unless your state has detailed under hood emissions inspections the unplugged egr valve shouldn’t cause a issue.

I would be warry of a car in perfect physical condition as it likely ended up in the junker due to engine/transmission issues.