VTEC Engagement/Oil Problem

I own a 1997 Acura Integra GS-R w/ 100,000 miles on it. Since a few weeks ago, sometimes when I reach the RPM that High Lift/High Duration mode kicks in, it lags a bit, then suddenly it seems like the VTEC wakes up. A friend suggested that maybe I needed more oil (VTEC uses oil pressure, for those of you unfamiliar). I added some more oil and it ran great for about a week. It's back to its old self again. The low oil lamp has come on a few times in the last few weeks as well.

I have inspected the engine and have found nowhere it is leaking oil, no loose hoses, etc.

Anybody got any idea on what might be going on?

What sort of oil are you useing?

And when was it last changed?

Oil that is to thick will badly effect the VTEC change over as oil pressure is used to lock the rockers together.
If the oil is to thick it will not flow properly through the small passages around the VTEC solonoid and into the rocker assembly to push the locking pin across.

Penzoil make a nice 10W-30 which is what Honda recomends, but anything close to that will work.
But don't use anything heavier than 20-50, and only use that if its an old engine with lots wear.


Also if the ECU detects low oil pressure it will go into limp mode untill the condition is fixed.
This means VTEC is disabled and the rev limit is reduced to around 7,000rpm.
Its normaly reset when the ignition is switched off, but if its occured a few times the ECU may have gone into limp mode permanantly.
You will need to reset it by either pulling the fuse or disconnecting the battery for 5 minutes.


And if your useing the right weight of oil, and have enough in, with a new filter, and your still getting a low oil pressure warning light and its tripping the ECU into limp, or your still getting problems with VTEC engagment then there is most likely a problem with the oil system.
Either the pumb has gone bad and needs replacing, or there is a blockage some in the oil ways.
Only a partial strip down and inspection of the oil pump and sump will tell you.

I'm using Mobil 1 10W-30 full-synthetic. It is due for an oil change coming up here. We'll see what happens then.

I know what the "limp mode" you speak of is. A little bit ago, the check engine light came on and I was lucky if I could get it to 5500 RPM! It seems to be working a bit better now, but I'm still a bit concerned.

I will change the oil and see what happens. If not... well, maybe I'll have to do some testing of the oil pump or maybe I'll take my oil pan off and check for obstructions in the oil pickups, etc.