***CODE 21 on a P13***

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TeamUrbanChaos

Certified H22 Super-tech
i just recently finished a H22 swap on my 92 honda accord and the ECU that i bought for this motor was a JUN chipped P13. now i was able to test the ECU before i put it in my car on my freinds H22 and it worked fine..it didnt throw any codes of any sort but one thing i noticed about it was that VTEC didnt kick in until about 5800 rpm's. the guy i bought the ECU from claims that VTEC should engage at 4600 and a secondary of 5800 but all it was doing was hitting really hard at 5800. now, when i put it the ecu in my car.. its threw a CODE 21. according to my haynes computer code book, a code 21 is a VTEC spool solenoid valve malfunction or circuit fault ...but accoring to some local perofrmance shops, theres isnt a CODE 21 on a OBD1 P13 which is leading many of my friends to believe that this ECU might be a P72 or even a P13 with P72 base maps because its redline and its VTEC engagement is the same as an integra and the ECU has no codes writen on it whatsoever... so now im really confused?? is there a code 21 and if there is, does it have to do with the VTEC??
 
integra gsr ecu's engage vtec at about 4500 to 4600 rpm
 
Originally posted by driver1@Dec 1 2004, 09:16 AM
integra gsr ecu's engage vtec at about 4500 to 4600 rpm
[post=424469]Quoted post[/post]​



well the ECU that i bought claims to engage at 4600 and 5800 but i only feel it crack at 5800...could it possibly be that the solenoid could be dirty or clogged up from sitting for so long?? the wiring is correct becasue i cross referenced my wiring with my friends h22 and its exactly the same but i havent checked the voltage.
 
i had a code 21 on my b16 civic, but i still hit vtec.. it turns out that my knock sensor came out...(yes, a honda dealer pulled the code)
 
well whats happening is that the ECU is throwing a code 21 but its also throwing a vehicle speed sensor code....now i kno that my VSS is actually dammage cuz when i was putting the motor in, the tab was broken off so i kno i need new one of those...the thing is...when i bought the motor, the knock sensor was broken..but being the ECU was chipped it dosent look for the knock sensor. and as far as the code 21, does that mean im going to need a new solenoid or is it that the current needs to be cleaned..i mean the motor probably sat for many years before i got it since its a JDM motor but at the same time do these things go bad from sitting???
 
Before you do ANYTHING else, you need to triple check the wiring. Check continuity from the vtec pin on the ECU plugs all the way to the solenoid. Resistance should be less than 1 ohm to the solenoid plug. Any more = problem.

Bad VSS will cause no vtec unless you are running HEAVILY modified code - beyond most mugen/spoon/etc. chips. - because ECU checks to makes sure car is going ~25mph before engaging vtec.
 
Originally posted by radnulb@Dec 2 2004, 04:36 PM
Before you do ANYTHING else, you need to triple check the wiring. Check continuity from the vtec pin on the ECU plugs all the way to the solenoid. Resistance should be less than 1 ohm to the solenoid plug. Any more = problem.

Bad VSS will cause no vtec unless you are running HEAVILY modified code - beyond most mugen/spoon/etc. chips. - because ECU checks to makes sure car is going ~25mph before engaging vtec.
[post=425197]Quoted post[/post]​


I was thinking the same thing, but less thought out. :lol:

Also, that JUN chip is junk. Your IAB should open at 4800 or so, and your VTEC should kick around 5000 to 5200. Your peak power is right around there. That big kick you feel is VTEC engaging more than likely. So, without VTEC, your engine is starving for air and fuel at 5700. Then, BAM!, full power at 5800. The VTEC engagement should be as smooth as possible. There is an article about finding the perfect VTEC transition point on this site.

So many of these fuckers tell you that you have two VTEC engagements, Bullshit! Some of them refer to the IAB as the first VTEC.

Get a real chip, and set your redline no higher than 8200 rpms. Any more than that and you will definitely hurt something.
 
Originally posted by tab+Dec 4 2004, 11:32 PM-->
@Dec 2 2004, 04:36 PM
Before you do ANYTHING else, you need to triple check the wiring.  Check continuity from the vtec pin on the ECU plugs all the way to the solenoid.  Resistance should be less than 1 ohm to the solenoid plug.  Any more = problem.

Bad VSS will cause no vtec unless you are running HEAVILY modified code - beyond most mugen/spoon/etc. chips. - because ECU checks to makes sure car is going ~25mph before engaging vtec.
[post=425197]Quoted post[/post]​


I was thinking the same thing, but less thought out. :lol:

Also, that JUN chip is junk. Your IAB should open at 4800 or so, and your VTEC should kick around 5000 to 5200. Your peak power is right around there. That big kick you feel is VTEC engaging more than likely. So, without VTEC, your engine is starving for air and fuel at 5700. Then, BAM!, full power at 5800. The VTEC engagement should be as smooth as possible. There is an article about finding the perfect VTEC transition point on this site.

So many of these fuckers tell you that you have two VTEC engagements, Bullshit! Some of them refer to the IAB as the first VTEC.

Get a real chip, and set your redline no higher than 8200 rpms. Any more than that and you will definitely hurt something.
[post=426419]Quoted post[/post]​



:D you couldn't have explained that any better!! that is exactly was is happening !! there is absoluately NO IAB engagement at 4800 rpm's or there after, and right about 5700 the thing cracks so hard its like a shot of nitrous or something and it pulls like a fuckin V8 ( well not really <_< ) but the things is still creating power even at 8400 and thats where i been shifting at only cuz im not lookin to blow the motor but im pretty sure if i drag that thing to the 9700 rev limit on it it might still create power. but im thinking about selling this P13 and gettin the stock p13 and just running a VAFC.

also i bought the VSS and the car is running perfect with no check engine light!!
 
Originally posted by TeamUrbanChaos@Dec 6 2004, 01:03 AM
:D you couldn't have explained that any better!! that is exactly was is happening !! there is absoluately NO IAB engagement at 4800 rpm's or there after, and right about 5700 the thing cracks so hard its like a shot of nitrous or something and it pulls like a fuckin V8 ( well not really <_< ) but the things is still creating power even at 8400 and thats where i been shifting at only cuz im not lookin to blow the motor but im pretty sure if i drag that thing to the 9700 rev limit on it it might still create power. but im thinking about selling this P13 and gettin the stock p13 and just running a VAFC.

also i bought the VSS and the car is running perfect with no check engine light!!
[post=426868]Quoted post[/post]​


Your P13 is chipped huh? Ask in the ECU forum how to disable the socket. There will be one jumper wire inside that you clip. More than likely, after visiting the PGMFI.org website, you will be able to recognize this wire.

I am assuming that the P13 is socketed. If the new chip has just been soldered into place, then you'll probably end up replacing it.

If you lived closer, I'd let you try out my stock JDM p13. It would be a great way to troubleshoot.
 
Tab...

The P13 is one of those ecu's that the main MCU is the chip. No jumpers to cut, and no internal programming.

You take the chip out, you render the ECU useless.
 
I was wondering about that. Too bad. He could get it rechipped with normal H22 maps and such, or go the P72 or P28 route.
 
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