JwapDreams

If I'm swapping a j35a3 into my civic and running the cls ecu, the correct harness to use is the j35a3 harness correct?

I'm pretty sure but I'd like to make sure. Thanks!

03-6/6

use cls6 and convert the engine to cls6 sensors. otherwise it wont run right or use auto ecu

JwapDreams

I planned on using auto ecu because I've read that manual ecu runs into limp mode and because the auto engine/manual tranny allows for upgrade to aem in the future.

If I'm running auto ecu, no need to swap sensors and use cls harness? Is that what you're saying? So I can just use the j35a3 harness with auto cls ecu to run my set up?

Karanx7

iTrader: (2)

You're expecting the Auto ECU to run a manual tranny?

JwapDreams

To be honest, I'm not exactly sure how it works either, but all across the Internet people have been saying the exact same thing.

Use the harness and ecu that comes with your engine. Hell, half the members here are telling me not to build a stroker and just use the j35a3 because it's close enough and they know I want to go 6 speed. Well, life got in the way so close enough is gonna have to cut it. I've literally had to cut my budget in half.

The engine is a j35a3. It's an auto engine that came out of an 02-03 acura MDX. So, auto engine, auto harness, and auto ecu. Not once has anyone mentioned to convert the sensors on this engine if I wanted to run manual. That being said, I have read if you want to run a true manual you can convert a j32a2 auto to manual because the sensors are different. I would assume that the j35a3 is the same. But that's not what I want to do and people don't mention that. I mean, if you "should" run the ecu that came with your engine, and its auto, why would the auto cls ecu not be a choice?

I believe I've read that people choose this ecu because it's simply better. The maps are better and the red line higher etc.

Now, maybe it's different because I'm putting this engine in a civic, but in this thread it's implied that you can trick the auto ecu and just manually shift the gears manually.

http://www.j32a.com/index.php?topic=72.0

I'm pretty sure that's exactly what AEM does too because they only offer it for auto engine/manual tranny combinations. But then again it's been a while since I've come back to this, I've been busy with life, and some ideas and information has been mixed up or forgotten.

I'd appreciate a response that's better than what you provided.

thoiboi

You've hard 3 posts so far and have not mentioned what transmission you plan on using.

JwapDreams

6 speed.

Currently looking at 03-07 accord or if I can find a deal, then 04-08 TL base.

Karanx7

iTrader: (2)

I'll help you out man, give me a second.

Karanx7

iTrader: (2)

So if you want to use a J35A3 with a manual 6 speed transmission, you will need to use either the AEM EMS 2 or use a CL-S6 ecu. If you use an automatic ECU without a RV6 module (not made anymore), you will run in limp mode. It's not as simple as switching some pins in order for the Auto ECU to ignore the fact that there is no auto transmission.

If you're planning to eventually get an AEM EMS 2, then do it now. It will be easier for your wiring, and it will save you money in the long run. If you get a CL-S6 ECU now, you will have to rewire everything and convert the engine to manual.

JwapDreams

So what youre saying is this:

If you want to run the j35a3 you have to convert it to a true manual set up. That means switching out sensors on the engine and running it with a modified harness with corresponding attachments. Only after the above is done you can use the cls6 ecu?

Or.

Leave the engine alone and get a modified harness that is wired to run manual transmission and use AEM.

Is this correct? In both examples it's the wiring harness that is different correct?

Karanx7

iTrader: (2)

There are two choices:
-Auto Engine Sensors - Auto Engine Wire Harness - AEM EMS 2
-Manual Engine Sensors - Manual Engine Wire Harness - Manual ECU

Idk why you are focused on modifying the wire harness. There is one harness for the manual setup, and there is another harness for the auto setup. No modification required.

JwapDreams

I'm 99.9% sure that you if you're swapping a j engine into a civic chassis you need to integrate your chassis harness with the engine harness you're swapping in.

I mean, other wise people wouldn't be asking for money to do so right?

I mean, if you can not integrate harnesses together that'd save me 500 bucks and that'd be a godsend.

Karanx7

iTrader: (2)

Oh, I have no idea about Civics. I'm just talking about the engine wire harness connecting to the ECU, which have different plugs for Manual and Auto.

There are two connectors on the driver's engine bay side that connect to the left engine bay wire harness.

JwapDreams

Yep. I'm not really sure either and now I'm pretty confused.

thoiboi

Probably a Civic forum would be best for you OP.

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