car = 88 crx si (cdn)
motor,etc = 1990 jdm b16/y1/pr3
problem = vtec not engaging
ecu code = 21


vtec wiring = good

solenoid, is @ 20 ohms when key is OFF, (supposed to between 14 and 30 ) , so thats good.

unplugged single wire vtec solenoid conector, and it is getting 10 volts with key ON, and 12 with car running

only code 21.

good circuit, not unplugged, possible defective valve?

clean fliter in solenoid valve, and good o-ring .. getting the right ohms. ? no vtec = sucks

any help?

Thanks!

 

What pin did you hook it up too? A8?

 

yeah, double check pin location, and make sure shes grounded out.!!!

courtesy of J katman!


hth

 

the wiring is FINE, it's not the wiring.

 

I had the same problem a couple weeks ago. Never really figured it out, but a reset of the ecu fixed it. You might want to try that.

 

reset , still nothing.

i don't always get code 21, sometimes it throws it, sometimes nothing

vtec worked in first gear, and 2nd gear a few times.. not always though?

losing oil pressure?

 

Might be time to get the pressure checked:

Idle = 24 psi (after warm-up).
3000 rpm = 60 to 71 psi (after warm-up).
Remove oil pressure switch to install test gauge. It's located on the back of the block, above the oil filter.

Double check on the pressure tho, this is for a D16....

 

This might sound stupid, but still make sure you have enough oil in your engine! If you do, I have no idea what is wrong with your car. Let us know when you find out!

 

sorry to bump this but i am having the same problem with no clear answer to code 21.

 

Same here. My oil pressure and voltages check out fine. However, whenever I throw a code the o2 sensor goes off (air/fuel ratio is getting mixed somewhere) as well as code 21 and code 22.

I think VTEC is kicking in, just can't feel it that well on an SOHC unless its built good.

 

try a different ecu

 

wouldnt having not enough oil throw off vtec code 22 not 21????just a question i also am having the same problem....im gettting code 21.....

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