Thread: Oil pressure light flickering at idle

Perhaps it is a sign that your big end bearings are worn ?

http://www.aulro.com/afvb/technical-...-1k-rpm-2.html

How many kms on the clock ?

147,000 on the clock, but this wouldn't be the first 200,000+ common problem I've encountered... I get the feeling it's been a tough life for my 300TDI or someone's done the dodgy on the clock!

Had a read and it sounds all too similar really. I might look into a new switch before anything else. Then if it happens again, look into new big end bearings.

For the moment it sounds like I'm relatively safe to continue with normal life since it's not even doing it all the time at idle? Just a brief observation at the moment...

I've just thought of something that might be important.....

For a while now I've noticed idle is slightly uneven. (Not sure what words to use here!) The revs counter bumps up and down a fraction. I've been meaning to try some injector cleaner, but perhaps that's going down the wrong path....

Your rpm fluctuations could be caused by a number of factors - I would be looking at the fuel supply side first -

has the water trap been cleaned?
has the filter been changed?
is the lift pump leaking or not delivering correct flow?

It's possible that the oil pressure light flickering could be caused by rpm fluctuations, or low idle speed.

otherwise it could be

oil type (brand & viscosity)
oil age (how long it has been in there)
crook oil light switch

and only after all of the above has been investigated would I be worried about engine wear (big end bearing) - while it is a possibility, I would think unlikely in an engine with so few kms (assuming it has been maintained and not drowned at any stage.

HTH -

Originally Posted by 87County

Your rpm fluctuations could be caused by a number of factors - I would be looking at the fuel supply side first -

has the water trap been cleaned?
has the filter been changed?
is the lift pump leaking or not delivering correct flow?

It's possible that the oil pressure light flickering could be caused by rpm fluctuations, or low idle speed.

otherwise it could be

oil type (brand & viscosity)
oil age (how long it has been in there)
crook oil light switch

and only after all of the above has been investigated would I be worried about engine wear (big end bearing) - while it is a possibility, I would think unlikely in an engine with so few kms (assuming it has been maintained and not drowned at any stage.

HTH -

G'day, appreciate the help...

has the water trap been cleaned? I assume this is the sediment thing near fuel tank? Tried a few weeks back and the plastic head snapped off. "To do list" is to take it apart and refit with a steel bolt.
has the filter been changed? Was waiting until I fixed above.
is the lift pump leaking or not delivering correct flow? Will do a visual inspection tonight.

oil type (brand & viscosity) - Unsure as it was refilled with the new head gasket which blew miles away from home and had a local mechanic fix it. Word on the street was he's a good diesel mech, so I would guess 15-40. I'm tempted to go back to my favourite Penrite HPR 5-40.
oil age (how long it has been in there) - 500kms
crook oil light switch - will order a replacement now.

That's some nice basic things to check before I hit the panic button. I can see the sump has been off before as whoever re-sealed it put a large bucketload of RTV back on it. So I hope that's not an indication of a previous drowning...

The oil pressure switch in probably US,look at the switch and if the plastic end is black it's stuffed and needs replacement. Pat

Originally Posted by Judo

G'day, appreciate the help...

has the water trap been cleaned? I assume this is the sediment thing near fuel tank? Tried a few weeks back and the plastic head snapped off. Most people have done it at one time or another
"To do list" is to take it apart and refit with a steel bolt. Good fix
has the filter been changed? Was waiting until I fixed above. OK - clean the sedimenter first and replace the bolt - then replace the filter
is the lift pump leaking or not delivering correct flow? Will do a visual inspection tonight.

oil type (brand & viscosity) - Unsure as it was refilled with the new head gasket which blew miles away from home and had a local mechanic fix it. Word on the street was he's a good diesel mech, so I would guess 15-40. I'm tempted to go back to my favourite Penrite HPR 5-40. WAIT - see if your other fixes have the desired effect - because you might yet have to take the sump off
oil age (how long it has been in there) - 500kms
crook oil light switch - will order a replacement now.

That's some nice basic things to check before I hit the panic button. I can see the sump has been off before as whoever re-sealed it put a large bucketload of RTV back on it. refitting the sump does require use of a glue sealant

BUT - I would wonder why they had it off at all ? can you find out ?


So I hope that's not an indication of a previous drowning...

HTH

Those sedimenters can be full of snot and really restrict fuel flow - but I think you would notice the lack of performance when driving if it was that -as Pat says replace the switch - but do that fuel supply maintenance first.