Renier

Sorry if I may seem ignorant asking this, but what is the hole there for and should anything be done with it to go for a responsible drive? I've always had it this way, the engine has ran but was never driven with, I'm in the progress of getting it to function again after a major engine failure and the mickeymouse work that was done to it afterwards in an attempt to fix it. Thanks in advance!

KBD85

If its the hole I'm thinking of its one of two places you can have you're oil pressure sensor. The other place is up by your distributor. So plug one, and use the other of your preference

Renier

Alright, thanks! This really takes my worries away. Best way would be to use a bolt to plug it?

Edwardgp

I think they are pipe threads, I could be wrong but I would try a pipe plug of the right size first.

RubberDucky

iTrader: (4)

There are two hole on the oil filter housing for the Oil Pressure Switch, take your pick, and use a brass plug for the other. Make sure you use thread tape or some kind of anti-seize on the threads.

Renier

Unfortunately my pipe plugs aren't the right size, I put a rubber plug in there for now but I can absolutely not guarantee myself that it'll stay put for long. The other point is between the distributor cap and the engine itself? The thing I see there is connected to a valve cover.

PS: Thanks for the advice! ;]

Renier

Hmh, this hose next to the distributor cap seems to be connected to the throttle body on my spare engine! I have two 2.8l V6's, one extra for parts, but neither of them have the hole next to the oil filter plugged. And by the way, my main engine has that same hole in the throttle body plugged, is this in any way dangerous?

Maverick H1L

iTrader: (8)

Not sure why that big hole is wide open. Should have a big plug in it. The OPS holes are about 8-9mm in diameter and are threaded. One may or may not be plugged based on the year of the engine and whether it uses one or 2 oil pressure units.

As for the TB situation...

On the 2.8, there is a big plastic pipe assembly that runs from the TB to a fitting on the back of the intake. This pipe is the idle air bypass pipe. You see, the 2.8 throttle body is a rather crappy design in that the idle air isn't directed back through the TB into the intake within itself. It relies on the pipe to carry the air the engine needs at idle to what is actually the PCV port on the back of the intake. If it's plugged at the TB, you will have to adjust the throttle stop screw to get a decent idle, but your idle speed WILL increase as the engine warms up instead of DECREASING.

You can make a replacement idle air bypass pipe out of 2 PVC 12mm plumbing fittings (a T and a 90* elbow) and a couple feet of coolant hose with a couple clamps. You will also need some fuel line hose that will go on the end of the PCV valve in the 2-6 cylinder head. And no, the actual GM idle air pipe is NOT available. Oh, and you will need to be creative as it comes to the vacuum port assignments for the charcoal canister.

Renier

Many thanks, man! Super on all of the information, will see what I can do indeed, and if I can perhaps find the derelict sensor somewhere.

Maverick H1L

iTrader: (8)

There is no missing sensor. That wide open hole is supposed to be plugged. Your OPS is in the right place with the proper plug above it. Go to a hardware store and pick up a 3/8 NPT tap and pipe plug. Or whatever the equivalent is in metric. Or measure the hole and pick up the proper cup plug. Either way, I would tend to think that oil will come out of that hole in massive quantities, as the engine runs, if it's not plugged.

Renier

Interestingly enough it didn't spout all over the place as the engine was running, like one would expect, while I can easily scoop out the oil with my fingers though they don't really fit in the thinner part of the hole. But thanks! Will do so on Monday, got a day off then.