oil pressure problems still!!!!

[01664gti]

Right i have been having a few issues with my mk2.Its a 1.8 8v,Anyway when its cold all is well but when it warms up the oil pressure drops and my oil light starts too flash.If i rev it the oil light goes off and the vdo gauge rises so i know its pumping

I took the sump off and cleaned the pickup and fresh oil and rebuilt it and it was the same so i just forked out for a new pump and fitted it and its still the same.

Its really starting to piss me off now,My car runs fine and no oil or water mixing etc just no pressure.
does anyone have anything to try?

Also what should a pb tick over at?? mine ticks over at about 750 rpm

How much oil does a standard pb engine hold when full???

Any help would be great as its really starting to rub me up the wrong way lol

[rubjonny]

what does the VDO gauge show when the light goes off

[01664gti]

when its cold it reads 3 bar and as the engine gradually get warmer it drops but as im driving etc it goes up but when im sat at the lights or stopped  and the cars warm itll drop down to 1 bar or less at idle but only when warm.

[rubjonny]

as long as its over 0.3 bar at idle and 1.8bar when reved to around 1.8-2krpm when the oil is warm then the pump is fine. just a case of do you believe the warning buzzer or the vdo gauge then

[01664gti]

Well when it drops down to about 0.5/1 bar i get the low gauge and the flashy light but i dont get any buzzer.I know it does work as its what alerted me to fit the vdo's etc.

Are there any breathers or anything else to check or is the oil system that simple??

[rubjonny]

0.5/1bar is fine, if the vdo is reading right then your pressure warning system isnt working properly.

check the blue wire to the side of the head, this is what triggers the light when the pressure drops below 0.3bar at idle.  it should be fitted to a brown or blue sender, not a white or black sender

[01664gti]

0.5/1bar is fine, if the vdo is reading right then your pressure warning system isnt working properly.

check the blue wire to the side of the head, this is what triggers the light when the pressure drops below 0.3bar at idle.  it should be fitted to a brown or blue sender, not a white or black sender

I took that out and fitted my vdo sender there,As per vdo fitting threads

[rubjonny]

aha, take the sender out again and check the switch rating on it. some are 0.3bar same as the mk2 one you took out, some are 1.8bar so are supposed to replace the one in the filter housing.  if it is a 0.3bar, put the old sensor back in and see what it does? or is that why you took it out in the 1st place...

if so then i dont know why the light is coming on when the oil pressure is over 0.3bar, doesnt make any sence!

[01664gti]

right,I just fitted the vdo sender into the t-piece and refitted the standard blue sender into the side of the head.I have no flashing anymore not even at idle and the vdo is reading just under 1 bar at idle.When i give it some revs my gauge goes up to just under 3 bar.

Am i about right then now??

[01664gti]

would an engine flush do any harm???.

What sort of stuff shall i buy???