skyliner34life

hey everyone i have a problem and I don't know where else to turn. so my brother owns a 2000 civic si with the stock b16a2 in it and vtec is not working. so about a year ago the head gasket went bad in the car and had overheating problems. we tried to take it to a shop to figure out what was wrong and they couldn't figure out the problem. eventually found out it was a head gasket and the head was cracked. so about 3 months ago my brother bought a used head and we both put it on and now the car runs fine with a little rough idle due to a bad o2 sensor. the problem we need help on is why vtec isn't working. we didn't forget to put any sensors on. we tested the solenoid with 12v power and it works. we also bypassed the pressure switch by splicing the solenoid to the vtec pressure switch wire and still didn't work. the only check engine light is an o2 sensor which I heard can cause no vtec but it's been bad for awhile and vtec worked. please help!

JRCivic1

The "used" head that you purchased... did you make sure that the VTEC oil feed port on the bottom of the head isn't plugged ??? The head may have been used in a LS/VTEC application previously and that hole would have to be sealed and fed externally. If you feel that this is a possibility, simply run an external oil feed line as if you were assembling a LS/Vtec or CRVtec engine and see if VTEC works. Your other choice is to pull the head off and take a look... remove the plug, replace the head gasket and re-install the head.

tony_2018

how do you know it isnt working if here is no CEL?

skyliner34life

we know it's not kicking in because we used to be able to hear it. JRcivic1 you are a genius thank you I'm 90% sure that's the problem. when he bought the head it said last/vtec plugged and we did not know what that meant and he went with it anyway. (not my choice it's his car)

B serious

iTrader: (1)

I think a plugged port would throw a CEL when the ECU noticed that the oil pressure wasn't there to feed the pin. Wouldn't it? A clogged VTEC solenoid screen throws a CEL.

Is the car at operating temp while testing VTEC?

skyliner34life

yes we waited till the car was at operating temp to test it and also made sure he wasn't low on oil which I know can cause it to not work as well

Former User

OP - Did you clean the screen?

JRCivic1

If you bypass the pressure switch by grounding one side and splicing the other side to the VTEC solenoid, no pressure code would occur because of the lack of oil flow.

tony_2018

only cel light he got is for an o2 sensor

slomofo

iTrader: (1)

Do you have a code P1259? If so, proceed to checking VTEC solenoid spool valve and pressure switch for proper operation. PM RonJ@HT for more info on how to do this.


Do you have a scanner capable of datalogging? If so, plug it in and drive down the street. Near 5000RPM, do you see the VTEC solenoid being commanded on?

If you don't have a scanner, go buy a cheap *** oil pressure gauge. Remove the VTEC oil pressure switch and install your oil pressure switch, then run the gauge into the car or tape it to the windshield wiper. Drive down the street and observe the gauge. Does it read 0 until about 5,000 RPM and then spike? If so, the head gasket was installed correctly and the VTEC solenoid functions properly. If not, then the head gasket was installed incorrectly.


Now that you've done that, I'll get to the part that has a 99% probability of being the problem.

Remove the valve cover.

Remove the upper timing cover.

Loosen the 14mm bolt for the timing belt tensioner

Tighten the 14mm bolt for the timing belt tensioner as you're applying pressure to the belt just below the intake cam gear.

Remove both camshaft rails. Do not remove the cam caps that sit below the rails.

Look at the cam caps and ensure they're in the proper location.

Now, flip the cam rails upside down and you'll notice they have holes in them. Look at the cam caps and make sure the holes in the rails match up to the corresponding holes in the cam caps. If the rails are reversed, VTEC will not engage.

If the rails and caps are in their proper order, you need to remove the head and check the valve train assembly for an oil blockage.

JRCivic1

Camshaft oil rails are interchangeable and thus can be placed over the Intake or Exhaust cam and will function perfectly in either location. The Honda part number for the rails are the same... meaning there is no unique "Intake" rail nor a unique "Exhaust" rail.

Did you have a VTEC pressure switch code 22 (CEL) before you did the pressure switch bypass wiring trick or did you wire it to the solenoid from the very beginning ??? If you did, then I am certain that you have a plug in the head limiting oil from traveling through the VTEC passageway between the block and the solenoid assembly.

tony_2018

I'm not even sure why he would need to do the bypass, the solenoid SHOULD have a vtec oil plug on there. Either the oil pump isn't flowing right or there's an oil passageway not getting oil.

He needs to confirm that the vtec solenoid is getting a signal from the ecu, something that should've been done a couple posts back.