Honda Civic / Del Sol (1992 - 2000) EG/EH/EJ/EK/EM1 Discussion

code 21

 
Old 06-08-2019, 01:39 PM
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Default code 21

why is my non-vtec b18b1 running code 21 when its not a vtec>>>since i already know that code 21 is for the vtec solenoid valve
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Old 06-08-2019, 03:08 PM
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Default Re: code 21

Wrong ECU for engine.
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Old 06-09-2019, 02:26 PM
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Default Re: code 21

i bought the 1993 honda civic with the b18b1 swap [or is this what the call an LS swap]not sure if the ecu is the right one, how would i be able to tell? the only other code, is code 5 which seems to be the map sensor.the place on the head where the vtec solenoid control valve goes has a cover on it and there are no wires for it to be pluged in if it was there. maybe i have the wrong harness and wrong ecu but i doubt that because i have no other issues
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Old 06-09-2019, 02:37 PM
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Default Re: code 21

Originally Posted by xamdam67 View Post
maybe i have the wrong harness and wrong ecu but i doubt that because i have no other issues
How could a non-VTEC engine possibly throw a VTEC code unless the ECU is a mismatch? Please respond.

Logic will always prevail.
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Old 06-09-2019, 06:43 PM
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Default Re: code 21

true, now thats the prob, how about you tell me where and or how i can resolve the issue ....hence how do i get a hold of the correct ecu for my car so i can drive and enjoy it
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Old 06-09-2019, 06:56 PM
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Default Re: code 21

Start by reading the label on the ECU. Then look to see what ECU you have here:

http://www.phearable.net/information...daeculist.html

Keep in mind that an OBD1 ECU can be chipped to run many different types of engines, so you may also need to open the ECU and look for a chip.

Code 5 is generally a vacuum hose issue or mechanical issue with the MAP sensor, so carefully inspect them.
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Old 06-09-2019, 09:48 PM
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Default Re: code 21

Originally Posted by xamdam67 View Post
not sure if the ecu is the right one, how would i be able to tell?
Originally Posted by muellersfan View Post
How could a non-VTEC engine possibly throw a VTEC code unless the ECU is a mismatch? Please respond.

Logic will always prevail.
To be fair, he didn't disagree and did ask the first time around.
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Old 06-10-2019, 05:22 AM
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Default Re: code 21

Originally Posted by TomCat39 View Post
To be fair, he didn't disagree and did ask the first time around.
Missed it.
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Old 06-10-2019, 05:42 AM
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Default Re: code 21

To be fair he missed it by a mile
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Old 06-11-2019, 07:49 AM
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Default Re: code 21

um ok took the ecu out and it says ....p28.. which means its NOT the correct ecu for the engine also i opened it up and low and behold it does have a chip in the place where the vtec chip is supposed to be therefore must be the wrong ecu as you instructed does that mean that the engine that used to be in this car was a vtec if so shouldn't there be a wire or plug to be used to plug into the vtec solenoid valve like i said i bought this car from someone who didn't know what they were doing or just didn't care now that is resolved where do i get the CORRECT ecu for this car???
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Old 06-11-2019, 08:19 AM
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Default Re: code 21

Originally Posted by xamdam67 View Post
um ok took the ecu out and it says ....p28.. which means its NOT the correct ecu for the engine also i opened it up and low and behold it does have a chip in the place where the vtec chip is supposed to be therefore must be the wrong ecu as you instructed does that mean that the engine that used to be in this car was a vtec if so shouldn't there be a wire or plug to be used to plug into the vtec solenoid valve like i said i bought this car from someone who didn't know what they were doing or just didn't care now that is resolved where do i get the CORRECT ecu for this car???
The chip can be removed and replaced with one that matches your engine.
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Old 06-11-2019, 08:40 AM
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Default Re: code 21

Originally Posted by muellersfan View Post
The chip can be removed and replaced with one that matches your engine.
first you say one thing then totally another still without answering my question WHERE CAN I GET ANOTHER ECU THAT FITS WITH THE ENGINE THAT IS IN MY CAR and or which ecu FITS WITH THE ENGINE IN MY CAR
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Old 06-11-2019, 02:02 PM
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Default Re: code 21

Originally Posted by xamdam67 View Post
first you say one thing then totally another still without answering my question WHERE CAN I GET ANOTHER ECU THAT FITS WITH THE ENGINE THAT IS IN MY CAR and or which ecu FITS WITH THE ENGINE IN MY CAR
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Old 06-11-2019, 06:06 PM
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Default Re: code 21

Originally Posted by xamdam67 View Post
first you say one thing then totally another still without answering my question WHERE CAN I GET ANOTHER ECU THAT FITS WITH THE ENGINE THAT IS IN MY CAR and or which ecu FITS WITH THE ENGINE IN MY CAR
Sorry that you don't seem to understand. IF the ecu is truly chipped, the programming of the chip could very well be for your motor. Or at the very least is a basemap for your motor and is there to be tuned to your exact engine which is a cost itself.

Google your motor ecu and you should see results of the ECU you need if that is the direction you wish to go.
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Old 06-11-2019, 08:07 PM
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Default Re: code 21

Originally Posted by xamdam67 View Post
first you say one thing then totally another still without answering my question WHERE CAN I GET ANOTHER ECU THAT FITS WITH THE ENGINE THAT IS IN MY CAR and or which ecu FITS WITH THE ENGINE IN MY CAR
Ok OP... you have two choices: 1) Find a B18B ECU (Part number: 37820-P74-A01 or 37820-P75-A01) OR 2) Contact Pherable or Xenocron and order a basemap chip from one of them... you can use their online order form. Once you get it, you would simply open up your ECU and swap the 28-pin chip that is currently in your P28. This choice assumes that your P28 ECU is fully functional and has no electrical issues.
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