ecu error code 21

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pwrfulz28

Junior Member
hi all, it's my turn to ask for advise. i got a crx with a b16 swap, the ecu shows the error code 21 (v-tec solinoid) i replaced the solinoid but error code still shows up. the car runs fine until it gets into the v-tec area and cuts off and on. it's also weird that thats the only code. no O2 sensor code comes on even thow it's unplugged.

i will recheck the wiring. but if anyone has run into this problem i would like to hear from you or if anyone has suggestions. thanks all and have a happy thanksgiving
:worthy:
 
CRX presume OBD0.

I'd check your wiring. I'd be willing to bet lunch you have a loose wire, wire grounding out or other such nonsense.
 
Originally posted by radnulb@Nov 26 2003, 06:43 PM
CRX presume OBD0

i didnt want to presume, ive seen people will throw a obd1 engine in there and a obd0 ecu, and wonder why it dosen't run right.
 
the computer been used is a pr3 and the engine is obd0 89' jdm. i rechecked the wiring to see if everything was tight and it is.
 
the last thing to try is to check the ECU. Replace it with another known good PR3 or PW0.

If this is not possible, splice a switch like so:

+12v -----switch----- vtec solenoid

try flipping the switch while you're going down the road faster than 4400 RPM. You should feel the difference if vtec engages. If it does, you know your solenoid is fine and either your ECU or wiring is fubared.
 
thanks for the info. i put another ecu and still shows code 21. i'm having second thoughts about the wiring being right. i will see about getting another pin chart and wiring diagram to make sure it's all correct. the place that i got the engine supplied the info on how to wire it up, that only 3 wires needed to be added.
once again that's for the help :spin:
 
Check to see if the solenoid engages or not by just using a straight source witht he motor off, you should hear a click, and maybe check your oil level also I've heard of that throwing it off myself.
 
the valve works, i hear it clicking. when i gun it it makes the car run like if the engine is out of balance(when v-tec has to kick in it shakes) i'm going to manually jump the vtec will driving and see what happens :blink:
 
I thought it was 4 wires.

1.Knock sensor
2.2nd O2
3.VTS
4.VTEC oil pressure switch

Iam also curious to know what harm it would do to bypass the KS? (knock sensor)
 
not lean enough to cause problems. Vtec cam needs more fuel than non-vtec cam. So if the ECU thinks is OFF vtec and you have vtec wired ON it will run a little lean.

big fucking deal. Don't drive from coast to coast with it miswired mmmkay?
 
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