SKU: 16484300700

Hondata Reflash - Civic Si 2002-2004

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Description

Hondata Reflash - Civic Si 2002-2004Reflash your 2002 2004 Civic Si engine computer. Fuel, ignition timing and cam timing optimized. Rev limiter raised to 7700rpm. 10 12 peak hp gain depending on the dyno and modifications 4 9ft lb torque across the rev range Power peak raised 400 rpm from 6300 rpm to 6700 rpm (higher with headers) 0 60 mph times improved by 1 second. Fully dealer compatible works with all Honda scan tools and equipment. This is for an ECU reflash the ECU is not

Reflash your 2002-2004 Civic Si engine computer.

  • Fuel, ignition timing and cam timing optimized.
  • Rev limiter raised to 7700rpm.
  • 10-12 peak hp gain depending on the dyno and modifications
  • 4-9ft lb torque across the rev range
  • Power peak raised 400 rpm from 6300 rpm to 6700 rpm (higher with headers)
  • 0-60 mph times improved by 1 second.
  • Fully dealer compatible -works with all Honda scan tools and equipment.

This is for an ECU reflash - the ECU is not included.  Hondata does not sell direct - the reflash must be purchased from a Hondata dealer. The ECU reflash form must be sent with your ECU.

We do not recommend the use of nitrous or forced induction for this reflash. For these applications use the K-Pro.

We recommend that 91 octane fuel be used with this reflash.

Warning

Within the USA this product is legal only for racing vehicles which may never be used upon a public highway.

Restriction
Sales Region US
EPA/CARB status (USA) Competition vehicles only
Vehicle
Model Civic
Year 2002-2005
Market US
Trim Si
Engine K20A3
Transmission MT
ECU
Part Number 37820-PNF-A01 to 37820-PNF-A12

 

2002 Civic Si, stock and with K20A3-Si Flash program.

Tuning notes

This tune is for 91 octane pump gas. The reflash has not been tested with 87 octane fuel. In the graph above, the change in octane was worth about 2hp and the tuning 8-10.

We recommend that 91 octane fuel be used with this reflash.

For consistency in dyno testing we suggest you follow the dyno procedure outlined here.

The K series ECU, in order to be re-programmed must have a functioning immobilizer system. Three items must be sent to Hondata: the ECU, the ignition key and the immobilizer. The immobilizer works as normal after the ECU has been re-flashed.

Tools needed:

  • Philips screwdriver
  • 10 mm socket and drive
  • Time needed : 10-15 minutes

Removing the immobilizer (Civic Si, RSX / Integra)

Under the steering column remove the three philips screw holding on the bottom plastic cover.

Depress the bottom cover along its top edge where it meets the top cover to separate the plastic clips. Rotating the steering wheel 45 degrees can help.

Lower the steering column and remove the bottom plastic cover from over the height adjustment lever.

Unclip the green connector immobilizer connector and unscrew the securing two philips screws.


RSX ECU removal

The ECU is located in the passenger's footwell. The kick panel is removed after depressing the centers of three small plastic buttons around the front covering panel.

Unplug the three wiring connectors and remove the two front most 10mm locating bolts, plus the rear bolt. The ECU will slide out easily - if it does not, then check that the rear bolt has been loosened or removed.

K20A3 Civic Si ECU removal

The Civic Si's ECU is located in the passenger's footwell behind the glove compartment.

Unclip the lower plastic panel:

Unplug the three ECU connectors.

Remove the lower two 10 mm bolts.

Open the glove compartment and push out from behind the two bump stops. The glove compartment will drop after this is done.

Undo the last 10 mm bolt and slide the ECU down.

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 16484300700

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Ilein
Omaha, US
★★★★★ 1
Not Leak Proof
Size: X-Large: 28" x 34"
horrible do not buy! leaks threw and caused a permanent stain and smell. thought it was good but after a week i noticed the smell and lifted up the mat there was complete pee under.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 12, 2026
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Jarett
Waukegan, US
★★★★★ 5
Great investment
Size: Small: 24" x 24"
It catches the pee that runs off the pad, great investment!!
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Reviewed in the United States on February 12, 2026
K
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Karen
Battle Creek, US
★★★★★ 2
It doesn’t stop leaks from the pee pad.
Size: X-Large: 28" x 34"
I’m trying to figure out how not to have leaks occasionally. I’m going to call the company to see if there’s something I should be doing.
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Reviewed in the United States on January 3, 2026
D
Verified Purchase
Donna Martin
Phoenix, US
★★★★★ 5
FANTASTIC PAD HOLDER
Size: 28'' X 34'', Size: 28'' X 34''
Amazon Basics Dog Training Pad Holder 28X34. I'll start out by saying I wasn't too sure about it, when I got it. It is awkward to put the pads in by yourself if your short as on each end the sides have to come up together and it’s big, however, I've done it five times alone now and it’s doable. There was no smell, it arrived in perfect condition. My husband was home and we set it up together, I walked into the bathroom to get a soiled pad I had keep to put on it for her to know what to do came back and she had already used it and she’s only four months old. I love it love it love it, it’s not too big, but it’s her home too, and we have it in the living room where we spend a lot of time as we’re retired. When she gets a little older, we will probably move it to another room, but for now it’s staying there. After she urinates, it goes down to a very pale yellow color I have been able to use one pad for all day, however, she does have a pad in a under bed tote in our master bathroom. We’ve had a few guests over and if she hadn’t used it they didn’t even know what it was. I highly recommend it. I have been using pads in an under the bed tote for over 10 years and this is a welcome audition. You won’t be sorry if you have little ones that go in the house.
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Reviewed in the United States on January 1, 2026
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Mariana P.
Lake Worth, US
★★★★★ 5
Very easy to use and clean
Size: 22'' X 22''
Saved my pad training with my puppy. It's firm and easy to clean. It holds the pads well for the most part, but sometimes my dog gets a little crazy and it comes out, but I don't think it could be better. Still give a 5-star!
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Reviewed in the United States on May 3, 2026

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