(P13 code-23) (Chipped ecu code-21) H22

[accordict]

Ok so I dont quite know what my question is......... So My chipped ecu throws a code 21 After the first time it hits vtec then wont let me do it again..... So.... I am also going back to stock ecu P13 and I get a code 23....But not 21

So does the knock need to work for vtec?
Cause my chipped ecu bypasses the knock, then throws a 21 for the vtec after I hit it once....So I dont get it

Yes I checked wiring and continuity

any thoughts or past problem would be a help......

[mozzandherb]

what ecu have you chipped?

[Shag Wagon]

Sounds like a bad program maybe?

[HondaBob]

It's weird to me how when people have a problem with anything engine related, they automaticly go to their chipped ecu. Not saying its not the problem, but go through your vtec system first, and make sure that there isnt really a problem with it.

Bust out your volt meter.... its time to go digging.

Your throwing the code 21 for the vtec solenoid valve. It may work, but you may also have a short somewhere, and the ecu is picking up on it.

take your volt meter, and switch it to ohms. Unplug your ecu from the harness. Go to your vtec solenoid, unplug it, and ohm the vtec solenoid wire coming from the solenoid to a body ground. there should be 14-30ohms. If not, check the ground at the solenoid itself. If your vtec solenoid ohms out at the solenoid iself, but not on the body ground, you need to remove your vtec solenoid bolts, and clean off the mating surfaces between the bolt head and the solenoid, along with cleaning off your body grounds. If the solenoid ohms do not check out either way, replace the vtec solenoid and recheck if the problem went away.

If the solenoid itself checks out, go to the other side of the harness. Check for resistance between the vtec wire going to the ecu, and body ground. If there is resistance, you have a short somewhere in the wire. Remember to have your ecu unplugged. If you have a short in the wire, you can try to track it down, but it's easiest to just run a new wire directly to pin A4 on the ecu.

If that checks out, Test the wire to the positive terminal on your battery. If you have any continuity, again, you have a short somewhere. repair or replace your vtec wire.

If everything checks out so far, test the continuity between the vtec wire and pin a4 on the ecu. there should be a 0 ohm resistance, or full continuity. If you have anything other than that, your wire or connector between the engine and cabin harness is in bad shape. Its either corroded, frayed, or about to break. Again, you can go through your harness and try to find out whats wrong, or replace the wire.

If everything checks out, go back to the ecu side of the harness, and double check that there is no continuity between pin a4 and ground at the ecu.


If everything checks out, THEN look at your ecu as the culprit. Different ecus react differently with vtec system issues. If you have a solenoid out of spec, some ecus will not pick up on it and it will still work. Same with if you have a small short in the wire.

I hope this helps. Definatly do go through the wiring before swapping your ecu.

[accordict]

It's weird to me how when people have a problem with anything engine related, they automaticly go to their chipped ecu. Not saying its not the problem, but go through your vtec system first, and make sure that there isnt really a problem with it.

I was switching to a p13 any way, and I did check everything.... it came out at 18 ohms..... The wires are new as for the swap my car didn't have vtec so I had to add the four wires... But I will do it again exactly how you said, and see if there is anything different... also, I have not taken the solenoid off of switch, just block so I will start there b4 I go through all the wires again... Thx