no vtec, code 21

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kyleirwin

Retired OG
i just swapped a 1st gen jdm b16a w/ hydro gsr tranny into my '95 dx coupe. the ecu i'm running is a p28 running uberdata with the vtec pressure switch disabled. i have the hasport vtec subharness, i ran the green wire in the harness from the vtec solenoid to pin a4 on my ecu. it's throwing a code 21 (vtec solenoid) and i can't seem to figure it out. i've even tried running a wire stright from the solenoid to pin a4 without the subharness just in case hasport screwed up somewhere but that didn't work. i know uberdata is all chipped right 'cause my rev limiters i've set are working. i tried running direct power to the solenoid and it popped fine. i've checked the screen on the solenoid and it's clear as can be. i'm running out of things to try and am hoping that somebody here can help me out. thanks.
 
should be pleanty... put just over 4.5 qts right after swap. but even if that was it, it wouldn't throw 21 would it? what makes the ecu throw 21? like what signal is it supposed to get from the solenoid to know that it's there and/or functioning properly?
 
why is the vtec pressure switch disabled?
 
Yea, I don't think it would either, just the first thing that popped into my just woken up head. Let me crack the book.....

Ok, only thing that causes a CEL 21 is 1) a bad soldenoid 2) not getting correct ohms at plug 3) No continuity between either the canon plug and ECU, caon plug and solenoid, indicating a break r miswire somewhere.

So, somewhere in your wiring, something is not connected right, or well. I don't think it's you solenoid.
 
i've tried the wiring a couple different ways, neither go through the cannon plug so there's nothing to go wrong at the canon plug. i've used the vtec sub harness from hasport as well as just running a single wire stright from the solenoid to a4. i'm pretty much as sure as i can be that it was setup correctly both times. the vtec pops when i give power to it, is there any other way to test if it's broken? i don't know how to test ohms, but i have a meter in my garage, so i'll do some research and go try that. thanks for your help.
 
hey im getting the same exact problem with my 99 lsvtec teg, I am getting cel code 21 and i tested the ohm @ the solenoid, good @ 18. I also checked straight power to solenoid and it closes okay too. I also have the 1 wire vtec upgrade from ecuhacker.com (disableing of the vtec pressure switch) so please let me know how you make out, maybe we can get each other thru this.

btw i just sent my ecu back to ecuhacker.com to get reproggied and see if that help, ill lyk......
 
i tested the ohms and got 22. i'm not sure i did it right though. i just took the 'lil voltameter thingy and set it to the 'lil omega sign and touched the red prong to the pin on the vtec solenoid and the black to a ground, is that how you're supposed to do it?
 
22ohms is good, should be between 14-30. All I can think of is something in teh ECU is screwed.

Maybe if you can, wire it OEM, and use a OEM P28, or P30, just to rule the ECU in or out..
 
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