2000 civic si
b18c5 swap

I purchased the car 6 months. First vtec would never engage. After a few oil changes, i would hear vtec engage and then disengage through the 5700 to 8000 range. Almost sounded like a hissing noise. The hissing noise turned out to be the vtec pins trying to lock the rocker arms but engaging and disengaging. So far i have swaped out the selonoid and pressure switch. Then I purchased a oil pressure tester and tested the oil pressure port next to the selonoid and at 5000rpm i get 25 psi. Which I believe 57 is required. Then I tested the oil pressure next to the filter from the sending unit and at 5000rpm i get 90psi. The screen is clean in the selonoid. What would cause the pressure to be so low to the selonoid.

The screen is clean in the selonid
The oil pan has no dents
no oil leaks

Any help would be greatly appreciated. I've already searched the forums and found no helpful info on low oil pressure to the head.

 

i don't know if this is possible but it almost sounds like the solenoid isnt opening the valve all the way....how much voltage do you get at the solenoid when it should be opening

 

I swapped out the selonoid with another one. The selonoid works. theres just not enough oil pressure to lock the pins. i just can't figure out why there is 90 psi at the sending unit and only 25 psi to the pressure port at 5000rpm.

 

None of that is right ur oil pressure isn't suppose to go over 80psi and at the Vtec oil pressure test port u should have 50 - 60psi at 5k. What oil pump do u have? Sounds like the oil passage is partailly block somewhere tho.

 

it is the integra type r oil pump.

 

not true I get 80 psi with a b16 at the pressure port when vtec engages. It does seem like the passage is blocked somewhere but there is really no where for it to block in between the two ports...given the fact you tried two. What I was saying before is if the solenoid is getting a weak voltage is it possible it is not opening all the way....but I thought solenoid were pretty much all or nothing so i don't know if that makes sense.

 

the oil passage coming up from the block to the head is probably clogged with rtv dirt or some sort of junk you could try taking off the solenoid and blowing some compressed air into the orifice

 

When I did the oil pressure test I manually engaged the selonoid to the battery and and reved up to 5000rpm and got around 25 psi. When I engage the selonoid at an rpm above 4000rpm I can actually here a bad clicking sound (not the selonoid)inside the head which I belive to be the pins trying to engage. As soon as I unplug the selonoid, I can rev the engine up and the clicking sound disapears. I am going to try shoot threw the ports with a blow gun to try to see what happens.

 

In for resuts

 

Dude read my post again before saying not true, I said it shouldn't get OVER 80psi becuase in all stock honda oil pumps is a check valve in the pump to prevent that.

 

not sure if you read my other post. check the o ring under the cam cap

 

you are still wrong. at redline when vtec is engaged i have seen oil pressure reach 98-100psi. when cruising up the freeway my car sits at 92psi oil pressure. 80 psi is the MINIMUM you want to be sure you have enough pressure and tehe oil movement is sufficient for the working motor.

 

does anyone know how the oil is directed from the oil pan to the head selonoid itself. Iv'e tryed to look up vtec oil passage ways but had no luck. The motor was directly bought from acura of las vegas. brand new. the honda mechanic which did the engine said the head was already assembled and all he had to do was adjust the valves.

 

did you check the o ring under the cam cap

 

persistance is key. haha. i agree with you. my buddy forgot to replace his o-rings under the cam plates and it made all sorts of weird things happen. replaced them next day and it was out crushing again

 

i will check the o-ring and ill let you know

 

Where do u have ur oil pressure gauge hook up at?? In the head?

 

my OP guage is right off the block at the stock sender unit. i re-wired it in to read to a digital gauge.

 

And u have a stock oil pump? The 2 engine's I have an oil pressure gauge on does not go over 80psi. I mean it will spike about 82 then the check valve opens and it goes back to 80.

 

yea i run a OEM type r oil pump. the fact my car is boosted may increase the oil pressure some as well. (i have no oil restrictor on the turbo right now) a know my buddies semi built lsv runs about 85 on the freeway. what motor do you run? im sure it fluctuates from each application.

 

Minimum on mine is 15psi at idle and 80psi max at WOT. I know in the head it verys by RPM tho. My GSR is boosted too

 

hmmm weird. yours is wired the same spot? at idle i an at about 25-30psi. i know bearing selection and tolerances effect oil pressure. tighter bearing = higher OP. i also spuna bearing because of improper tolerence (thanks machine shop) so that could have been and indicator. my dad has a built small block, it runs 80-88psi WOT.

 

Yeah, I have a 454 that runs 60psi at idle and 80 psi WOT (not a stock pump tho). I have a mechanical OP gauge off the sending unit, bearing clearance is .0015" and an oil restricter on my turbo, stock GSR pump using 5w-30 oil. This is very weird to me, when I put the OP gauge on my LS/Vtec it was 20psi at idle and also 80psi at WOT using a Type R pump and 10w-30 oil with bearing clearance at .002".

 

yea motors are weird things. you never know what you can get. i think if i got a oil restrictor for my turbo it would change my numbers dramatically, especially when its warm out. i use the electronic digital gauges, i dont know which is considered more accurate.

 

I just find that so weird for them to b so much different, so to the original poster, now u have a better idea of what things r for other ppl and what may be going on with your engine and the O-ring under the 3rd cam cap will drasticly affect the oil pressure in the head and Vtec won't engage.