Hey folks. The other morning while i was just setting off to go pick up the girlfriend, my oil pressure light came on and started beeping at me. I had only just started the car (from cold), lit a fag, then rolled down to the bottom of my street to turn (about 10 yards), I'd just selected reverse when i heard the bleep, looked at the dash and saw the oil light on so swithced it off double quick. After pushing the car out of the middle of the road i popped the bonnet and checked the oil level, it was still at the MAX mark. Took the cap off the engine and there was a nice amount of oil up in the top end on the cams etc, nothing bad going on in there, mayonaise etc. The trouble is that i'm not quite sure what it is or where to start in diagnosing it! Now that the cars been sitting for a few days i don't want to fire it up since the oil will have drained from the top end and turbo knowing these engines have a record for oil pump failure. I've never had the oil light come on at low rpm like some people have had just before pump failure. As i see it, the list of possible problems is: Water causing a short somewhere since i'd just washed the car. Oil pressure sensor. Oil pump pick up strainer clogged. Oil pump fubared. I've had a scan around and can't for the life of me find the oil pressure sensors on the thing, which is the first thing i wanted to check since i had a pressure sensor fail on my mk3 which turned into an oil pistol and soaked half my engine bay in oil and half emptied my sump. Any advice on the sensors location and a diagnostic plan of action would be much appreciated, also, is it possible to read oil pressure via vag-com? Cheers guys.
mate, remember with the s4s, there were sludge issues with those engines due to dodgy service intervals. that mainly effected the late ones, and yours is an agu. look inside the oil filler cap and see how much gunge is in there. it wont hurt to get the sump down and clean the strainer. the cleanest ones ive see though were on AGUs.
RTFT! Already said that it was clean as a whistle inside the rocker cover. Was planning on dropping the sump today but it's chucking it down with rain outside, after being sunny and warm for the last 4 days while i was at work, typical!
Change the sensor. Easy job, quick job, done job. I had this happening. You will see the light and buzzer go off after I think it's 2700RPM (maybe not, but there is a value, where as soon as it goes higher, it will buzz). CHange it, it's cheap.
Got a new sensor, going to go out and change that in a mo. /crosses fingers! whats the best way to disable the engine btw? to stop it starting when i crank it over, just to see if theres oil moving around before starting it up.
Nope, not the sensor [:^(] Whipped the old one out, cranked the engine briefly and oil spurted out the hole so there's SOME oil circulating. Put the new sensor in, held my breath and fired it up, no oil light on, win! waited a moment to make sure the top end didn't start to rattle or anything, went to move the car to back outside the house and as soon as it got over 2krpm on comes the red light and it starts beeping at me! Gutted! Before there's oil circulating at a good pressure at idle, but not at higher rpm, i'm thinking it's maybe the oil strainer, maybe flowing enough oil at low rpm but starving the pump at higher rpm. Either way, that's the next thing to look at but will have to wait until the weekend sadley. Feckin' cars!
oil pickup strainer blocked it seems that its a common problem. at least its in a golf the passats are a pig of a job to do due to being fitted the wrong way in the car
I had the same problem with my MK4 (2002 AUM). I was driving to work and the oil pressure light come on. The oil change was long over due and it had eventually blocked up the pick up pipe and strainer. I just drained the oil, whipped off the sump, removed the pick up pipe and thoroughly cleaned it. Changed the oil and the filter, and its been fine since Im going to change the oil regularly now! Will only take a day to do, not rushing...
Gutted Spent the day today getting the sump off (those two bolts on the gearbox side are a proper pain in the butt!) and removing the strainer. The strainer was in a pretty bad state, clogged up with nasty grit like crap. Anywho, spent 30 mins getting that spotless, then another 30 mins cleaning out the sump, which is now also spotless. Refitted the strainer and the sump, changed the oil filter, filled up with new fully sympathetic () and fired it up... Tappets rattled like a barsteward for about 3 seconds, then fell silent and she ticked over like a swiss watch. So as you can imagine, spirits ran high! Stopped the engine, checked and toppe dup the oil level again then fired her up, sweet as a bell. Left her idling for about 30 seconds then slowley increased the revs over 2000rpm and the red oil light came on, along with the beeper so i killed the engine quick sharp. This is really fecking annoying, because before it pumped up the tappets it's clear there's SOME oil pressure, yet as soon as you take it to 2k rpm all hell breaks lose and the dash starts swearing at you. Surely the pump should make MORE pressure at higher rpm? Grrmurr, looks like fitting a new pump next, but i'm skint until the end of the month [:^(]
Gutted for you mate. I done exactly the same as you and it ran fine after. I did buy a new pump from gsf, but thought i'd try it with the cleaned up strainer and it ran fine. Maybe the pump is clogged up?
The oil filter was pretty damned heavy when it came off (after the oil was tipped out) so obviously pretty full of sh*te. The oil that came out of it was satisfyingly normal though, no watery deposits, no burning smell, not to thin and not to thick. Possibly, just going to throw a new pump on it now, can't be ar*ed with the hassle of tearing it all down, building it all back up and it still not being fixed. If i bung a new pump on it and it still does it i'll scream, i swear! lol.
As soon as the oil light comes on in those I'd change the pump straight away. Had exactly the same prob with two if my friends cars. Take the sump off once and change pump and strainer. Least you'll get another 100k before doing it again. For the sake of around 60 its worth saving your engine.
invest in an oil pressure gauge, then you can see exactly what is going on. if you were closer to me i'd let you borrow mine just so you can see the pressures
Was thinking that myself, my old man has one but he can't find it, typical. Will change the pump anyway, then go from there, if it still does it either a can of petrol and a lighter or an oil pressure gauge. theres no rumbles, thumps, bangs, clatters or clunks fromt he engine so can pretty much say for sure it's not that, plus bearing wear doesn't generaly happen suddenly and would more than likely be worse at idle than at over 2k. Feckin cars!
Hope you get it sorted mate Its such a pain that you have to whip the sump of again. And use the sealant all over again, but hopefully it should sort the problem! I was going to suggest changing the level sensor but looking back you already have. Everything points to the pump now tbh. Also, just in case, have you checked the wiring going to the sensor?
Aye, i checked the wiring and it's all good, solid, no deterioration of the plastic, no funny kinks etc and it meters out ok so the wires not broken. Was bored and hung over today so gave it a wash and polish, felt kinda stupid washing and polishing a car that's sat up on axle stands, plus i'm only 5ft 8in tall so couldn't reach the roof! had to get my 6ft 4in mate to wash the roof for me!
Recently had the `same` issue with a daughter`s AUM .... service history prior to purchase was OK but nine months later Sump & strainer were filthy = knackered pump and top end was `toast` [:^(] Bearings and rings were OK.
