New member help '98 Passat 1.8T Auto

[JohnW78]

Hi,

First post - hopefully you guys can help me out a bit.

I picked up a 98 passat estate 1.8T AEB engine automatic gearbox - test drove it pretty extensively no funny noises or rattles - in general seems solid.

On the way home from the garage about 15 miles I guess, the oil light came on flashing red and bleeped 3 times - pulled up and checked the oil, level seemed ok, so started up and carried on home. Light came on and bleeped twice more, both times when slowing down to turn.

Today first I popped the sump plug drained the oil shone a torch up the hole and had a poke about in the sump with my finger - doesn't seem to be any sludge - if it had a sludge problem I was expecting a lot of sediment and not looking particularly good, however it looks pretty shiny in there really.

Whipped off the rocker and the cams seem fine nice and smooth nothing untoward there in my opinion tappets seem fine, breather isn't blocked.

Put it back together re-filled the oil with the specified fully synthetic 5/30 oil, fitted an oil pressure gauge in the blanked off hole next to the pressure switch.

Cold idle ~ 28psi
Cold 2krpm ~ (cant remember)
Cold limit ~ 70psi
Hot idle ~ 13psi
Hot 2krpm ~ 25psi
Hot limit ~ 40psi

On extended tick over the engine was running too hot - worked out that the viscous coupling wasn't working properly - fan was hardly spinning - fixed that with a new coupling, temp is ok now - around 90c when parked at idle, between 70-85 when driving.

Oil pressures are still much the same with the fan fixed - bit of a loss now what to check - loathed to take the sump off and look properly at the strainer because of the lack of sludge anywhere - no funny noises either.

Took it on a 30 mile country lane and dual carriageway test drive, light didn't return, no other problems either.

The pressures to me seem a bit low - are they typical of this car or too low - could it be a dodgy sensor or is there another problem I should look at?

John.

[Crasher]

The pressure should be an absolute minimum of 2 bar at 2000 rpm with an oil temp of 80 degrees using the recommend grade of oil such as a 5w/40 fully synth. From what you have said and done I would say that the oil pick up is partially obstructed by debris and if you avoid removing the sump you will destroy the engine and turbo, the turbo will have already suffered. My guess is that this is why the car was sold, people can tend to do dishonest things like that.

[JohnW78]

Well I'm not specifically avoiding removing the sump - thats actually what I started to do when I drained the oil - but it looked like a bit of a mission when laying on a gravel drive, when I had a poke about and a look it didn't seem un-toward in there

Where is the pick-up in relation to the plug hole?

Cant see you would really get rid of a car for a blockage when theres no obvious damage - putting in to an independent would be about 3-4hrs labour, doing it on the drive would be 7-8hr I reckon, not too scary.

J.

[Crasher]

3 to 4 hours, and the rest! The subframe has to be dropped first and then re-aligned with special pins when refitted (using all new stretch bolts) and the pickup in in the forward section of the sump but the only way to clean it is to remove and back flush it. I have tried blowing compressed air up the oil filter feed and this has helped me with repetitive blocked sumps once I had cleaned out the sump. One I did blocked up again five times in a few hours on the ramp, after I had scrubbed the sump, block sides, cam cover and head internals clean, it was clogged full of debris. I had to drop flushing oil five times before I got it to play ball, nearly had me on a mental ward that one!

The previous owner was probably told it would cost a few hundred to deal with and said they would get rid, I hear customers tell me this over and over again. I tell them they have a problem and they respond by saying they will sell the car, I leave it at that but I would love to challenge them as to the ethics of such a move. But then again, it is only garages and car dealers that are dishonest.

[JohnW78]

Like I say im a VAG noobie but it seems a bit odd - ive been around cars with virtually tar in the bottom of the sump with no problem - this seems relatively clean.

I'm not saying its not the problem, but as far as ive been reading the oil pump is on the verge of indestructible and in this car the tappets look fine, the big end and main bearings don't rattle, there is oil where it should be and there is no wear. I did buy an el'cheapo capillary pressure gauge from the local wilco but I'm being optimistic to think its too far out.

At the end of the day either the oil pressure is ok, or its not but, I'm running out of feasible malfunctions apart from the strainer or pick-up but you can see the strainer pretty well through the sump plug.

Assuming the worst what is your estimate on the hours to fix? I honestly thought with knowledge and the right tools you could get through it in a few hours? The Haynes (number one adjusting tool) manual claims its a 3 spanner job

J.

[Crasher]

If you don’t want to trust my remote by your text diagnosis, keep on driving it until it seizes and also destroys the turbo, just like countless hundreds of thousands of other VAG 1.8T (especially longitudinal installation) engines around the world. In the US, this was such a problem, even on relatively new cars, it nearly broke Audi US. Cleaning the oil pump pick up takes about six hours on a lift by someone who has done a few.

[JohnW78]

I see on eurocarparts that a new oil pump, strainer and pickup (well thats whats pictured) is £99.36 surely its easier just to throw the old one away and fit a new one if your going to the effort of removing the sump?

Just looking for a garage to do the work, somewhere in Hitchin or Stevenage would be good.

J.

[Crasher]

I recommend people have a new pump but often they will not pay the extra.

[JohnW78]

New pump, oil + filter fitted for £308 - took them a week to get round to it but I'm back on the road, next to fix the worst windscreen wipers in the world and get a load cover.