K20z3 not going past 5500 rpm's

K20 & K24
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K20z3 not going past 5500 rpm's

By keith_b03
- Tue Jul 21, 2015 7:31 pm #354869 Alright so I know this isn't a eg chassis but you guys always seem to have good input.

I have a 02 ep3 with a k20z3 swap with 6 spd tranny.
Car won't go past 5500 rpm's when driving. It used to just fine then one day it wouldn't. It's like it's hitting the rev limiter at 5500. Any help would be great thank you very much
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By keith_b03
- Tue Jul 21, 2015 8:58 pm #354871 I'm pretty sure it's the ecu from the 08 mugen si. That's where I get my swap from and yes there's a cel
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By Driv-it-hard
- Wed Jul 22, 2015 12:23 pm #354883 First thing on the check list is to run the codes, see what is going on and why the codes are there.

Let us know the codes and that can give us more of an idea.
Hang in there.
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By EconoBox
- Wed Jul 22, 2015 1:50 pm #354889 I'm not sure how you have the ECU from an 08 SI in an EP3... the EP3 uses different connectors and is mounted under the dash like an RSX. The 8th gen SI ECU is a sealed unit under the hood.

We have your engine model 'K20z3' please look and find which ECU you have and use an OBDII scanner and post whatever codes you are showing. Any Autozone or Advanced auto parts will pull your codes for free.

Honestly this swap should be running an 02-04 RSX Type-S PRB ECU with K-Pro and have wiring added to make a functional reverse lockout since you are 6 speed.
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By keith_b03
- Thu Jul 23, 2015 6:14 am #354906 Yeah I honestly don't know what ecu I have. I didn't do the swap I just got the car like this. And I can't get my brothers snap on scanner to read it very well it only says O2 sensor is out. But I'll try autozone in a bit and let you guys know the codes. Thanks a lot guys. [/img]
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By EconoBox
- Thu Jul 23, 2015 12:39 pm #354911 Once you've got the codes it is throwing post them up.

Check out the bottom of this link it will show you were the EP3 Civic Si ECU is located. Find the sticker on the side of it and see which one you have the number should look like this '37820-PNF-A11'(this is an example your part number may be different). I'd also suggest following the step for removing the ECU and using a Phillips head screw driver take the top off of the ECU and take a picture of the inside and post a picture and I will let you know if there is a Hondata system installed.

http://www.hondata.com/k20removeecu.html
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By Driv-it-hard
- Thu Jul 23, 2015 2:20 pm #354913
EconoBox wrote:Once you've got the codes it is throwing post them up.

Check out the bottom of this link it will show you were the EP3 Civic Si ECU is located. Find the sticker on the side of it and see which one you have the number should look like this '37820-PNF-A11'(this is an example your part number may be different). I'd also suggest following the step for removing the ECU and using a Phillips head screw driver take the top off of the ECU and take a picture of the inside and post a picture and I will let you know if there is a Hondata system installed.

http://www.hondata.com/k20removeecu.html


Econo is on point !
:thumb: :thumb: :thumb:
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By CopyLifted
- Thu Jul 23, 2015 10:14 pm #354919 I wonder if it has kpro? Check the ecu for a printer style usb port. Should also have a HONDATA sticker on it. If so, grab your laptop and install the latest kmanager software and hook it up to kpro. You can check the codes that way if it indeed has kpro installed in the ecu.

I'd bet it has something to do with vtec though as 5800 is where vtec crosses over stock. Does it rev past 5500 when to engine is cold?
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