1.8T oil pressure

[Jmac]

Hmm, problem with flushing is that fact it can push any sludge or carbon into the strainer that has a habit of housing it very well. Seen dozens like it. And it turns to coal. Check your oil cap mate, on the base if it looks like it has carbon build up , then you can be sure the guts of the engine has heaps. Strainer need to be removed and cleaned properly if it is the case, if you are suss on the oil pump too , change it as you are in deep enough at that stage.
Winding back i saw this on a few back in the UK. Someone used crap TESCO oil and when i saw the car i put nice stuff in. Only to be told of its poor service past. The lovely cleani oil thenm pushed all the bits into the strainer and the oil light never went off. Sump off an yep strainer choked.
It is the Black Death for an engine and if it has it bad enough there nearly isnt any turning back. It really pays to keep the service regular.
Jmac

[Transporter]

Well, hard to judge, if it would help or not without seeing the engine. As long as there is some oil pressure, it can work, only the thing is that engine and the oil pump could be worn out due to poor maintenance.
I suggest that you check for the sludge inside the sump through the drain plug hole with the L shape bent wire to see how much sludge has formed inside. If you find sludge with the wire than remove the sump and clean it, including the strainer. New oil will continue dissolve the sludge and oil filter will fill up very quickly so, change oil and oil filter more frequently for some time, if the oil pressure improves, if not repair or replace the engine or the oil pump.

[Jmac]

Well, hard to judge, if it would help or not without seeing the engine. As long as there is some oil pressure, it can work, only the thing is that engine and the oil pump could be worn out due to poor maintenance.
I suggest that you check for the sludge inside the sump through the drain plug hole with the L shape bent wire to see how much sludge has formed inside. If you find sludge with the wire than remove the sump and clean it, including the strainer. New oil will continue dissolve the sludge and oil filter will fill up very quickly so, change oil and oil filter more frequently for some time, if the oil pressure improves, if not repair or replace the engine or the oil pump.

Yep agreed, thats why a easy indication is looking at the oil cap, just on the twisty bit, if it has lots on it then its a good guide to what the rest is like. But yeah this is when a borascope would be great and they come at a reasonable price now. As always very tricky to diagnose anything really without sighting it for sure.
Cheers
Jmac

[t4 camper]

Thanks for the help guys.

The problem was "oil sludge", well blocked strainer more specifically.
The strainer is by far the smallest I have ever seen in any engine and has a shroud around it as well.
The sludge was more like pieces of hard varish or carbon.
We have had the vehicle about 8 months, wife bought from a work friend.
The original services were done as log book by Audi.
Some intermediate services were done by local mechanics and lube centres, not certain of the oil quality that was used in those services.

I did the job at home on the garage floor, about 8 hours for novice, no manual.
The strainer can be removed by lowering the sump but not taking it out.
The bell housing return prevents it sliding straight out. To take the strainer only out, clean strainer and back in you could 1/2 the time.

Steps for removal/refit.
Lift car, drain oil, remove drive belt and loosen A/C compressor, support on rope to lower and allow A/C filter/dryer pipe to move back. Remove torsion bar.
Front stabilizer bracket, sump bolts, 2 hidden bolts in rear of sump, flywheel requires rotation to allow recess groove alignment.

Support engine on lift, disconnect air house at throttle body.
Undo engine mounts bottom, lift engine about 50mm. Watch water hoses for pinching at rear top. Also supported/lifted transmission on small jack.

Remove engine mount brackets and front crossmember bolts, lower crossmember. Rear mounts still in place.

Remove strainer, 2x10mm bolts and dipstick, 1x 10mm bolt for plastic oil surge tray. Carefully slide out surge tray. Sump should wriggle out, near left side of engine. The right rear 16mm bolt will not completely come out of sump until it is dropped down at front.

Clean strainer, sump, oil surge tray. Soaked the strainer in petrol overnight to disolve the sludge, blew out with air hose. Degreaser to remove varnish and oil/carbon from side of sump above the oil level line, mainly on left side.

Re-assemble in reverse order, Sump placed over cross member, rear right bolt inserted in hole. Surge tray in, strainer in. Sump up, Turbo return line on, cross member up, engine mounts, A/C, drive belt, stabilzer, air hose, filter and oil.
Torsion bar, wheels need to be lifted/jacked slightly to get back on
Test oil pressure. Straight to 65psi, cold at idle, 75psi at 2500rpm.

Have a beer or 3, and deliver the car back to very happy wife.
Total cost, gasket glue and hand cleaner.

Checking the oil pressure was done at the sender located at the rear of the oil filter housing.
Specialist tools,
24mm hex tube spanner, oil pressure sender.
5mm hex drive x 200mm long required to get to 2 hidden sump bolts.
I use 2 small pulleys and rope to release drive belt tensioner, others will have a tensioner release lever.
I used a test gauge originally to check oil pressure, I did temporarily fit a oil pressure gauge, and test drove the car with it race taped to the windscreen.
The oil pressure sender thread is 10x1.0mmTPI, hard to find correct thread adaptors, I used 1/8bsp tapered gauge that I had only finger tight with rag to catch the oil leak.

I think it would be good preventative maintenance to test the oil pressure on these engines, about 1/2 hour to test. A weekend to fix.
The pressure relief valve is external to the engine, a 19mm bolt at front bottom of the oil filter housing holds the pressure relief spring in place.
Strainer not available separately, complete with oil pump, $450 retail.
Pressure relief valve not available separately, complete with filter housing $380. Oil Pressure sender $40. none needed thankfully.

Neil

[Transporter]

So, did you check the oil pressure after the job? And is it all good?

[t4 camper]

Sure did.
From post #1 before fix,

Cold was 25-30lbs (180-210kpa)
when engine was hot 20-25lbs (150-180kpa).

from post #14 end of para 8 after re-assembly.

Test oil pressure. Straight to 65psi, cold at idle, 75psi at 2500rpm.

Neil

[Golf Loon]

Nice write up mate, you did well to do that job at home on the floor.
I reckon you earned that beer.

[t4 camper]

Some strainer pics.
before clean


After clean

Neil

[Jmac]

Some strainer pics.
before clean


After clean

Neil

Nice, and thats the reason i say dont flush, where does it go????? to the strainer. Tough oil pump mate , working its nuts off to work. Itll be relieved too!!
Cheers
Jmac