mmasire88

I picked up a 2003 audi a4 several months back and for the most part it sits in my driveway. Generally short 15-20 minute trips here and there 2 maybe 3 times per week. Went out of town yesterday and about 3 hours into my trip the low oil pressure light popped up. I'm very familiar with the 1.8T motor, I've fixed several clogged pick-up tubes in recent years and I current own four different A4's all with 1.8T motors. Anyway, it seems to be very intermittent, the light would pop up, ding, and turn back off all within about 2 seconds and not show back up for another hour of driving or so. The engine was nice and cool, no engine noise, was still running excellent like normal. The car has just under 100k miles, I have oil change receipts, parts receipts that date all the way back to around 24k~ miles and it's always had synthetic oil changes within required intervals. I can't imagine the pick-up tube is sludged up already....the car has been meticulously cared for over the years. It was around 97~ degrees out today and that's when the oil pressure light was acting up, as soon as the temperature dropped I drove the car for nearly 4 hours straight without the oil pressure indicator popping up.

Only mods on the car currently is an APR tune. The last time I had a problem with a sludged up oil pick up tube it was on my 2001 b5 a4, the engine over heated within 30 seconds, the lifters sounded like they were going to blow out the valve covers. However, this car remains quiet and stays cool.

Prospeeder

If the car was driven very hard and not cared for properly, like they hot rodded it and then parked it and shut it off, then the turbo will cook the oil into coke and next start up it all floods into the oil pan and up into the pickup tube. Eventually it fills up enough to lower pressure. When this problem first started happening it was on 100k mile or less cars. Even synthetic oil will cook to coke if the turbo is hot enough. You say its tuned so that an indicator right there of harder than average use.. I would for fun replace the sensor if you havent already. If that doesnt then remove the pan.

mmasire88

So far since I posted that, I've been driving it around a bit more than usual and I have not seen the light pop on again. Not sure what was going on with it that day. I may go drain the oil, pull the pan sensor off and see if I'm able to take a small peak inside there.

mmasire88

I went out and drained the oil, I didn't have to pull the sensor to know there was junk in the pan! As it was draining the flow was immediately interrupted by big yellow/orange chunks of old broken pieces of dipstick. I cleaned my oil pan (not the engine oil pan) prior to doing the oil change so I knew whatever drained into the pan came from the motor. Mostly, it was all orange/yellow pieces from an old dipstick breaking but I also found some very gritty material on the bottom and it's pretty small so I have no idea what that could be, almost felt like sand (not much, but it's there). Also, the car had the smaller oil filter on it which I replaced with the big fram filter.

It's hard to diagnose the problem when it has only done it a couple times in the same day, and than goes away! I'm not ready to pull the pan yet, I just finished swapping the motor in my truck and I'm still recouping from that.

ECS Tuning-Audi

Biggest question was it the red oil light or the orange oil light? If its the red oil light there is a pressure issue or the sensor is failing. My suggestion would be if you are getting a red light have the pressure checked manually with a gauge and verify its meeting the proper values at the specified RPMS.

If you are getting the orange light this is just the level sensor. These are notorious for failing. Double check your oil level is good, if it's good chances are the sensor is on its way out. Next time you change the oil pick up a new sensor and swap it out once you've drained your oil.

I hope this helps!

Jason

Prospeeder

The sandy grit is what packs into the pickup tube from the turbo, thats coke, its oil cooked into grit. Get that nasty fram filter off that thing. Have you ever looked inside one? Its got no drain back valve, cardboard, and 1/4 of the pleats and material oem filters have. If your stuck with local parts stores Napa Gold, Wix, anything top end. NOT fram anything. Horrible filters.

And stop driving it and pull that oil pan, it can block over 50% and not turn the light on. You want your poor engine starved of 50% or more of oil volume....Remember volume and pressure are two totally different things. You can have very little volume and pressure, and tons of volume, and no pressure. They are not totally dependent on each other.

mmasire88

Normally, I buy mobile 1 filters for my Audi's. However, they had 0 in stock at the time. Also, the car is not driven on a daily basis, mostly just start it up and drive it around once or twice a week to stretch it's legs.. Thank goodness I love hoarding Audis!

mmasire88

It was the big ugly red light that nobody likes to see. Pop up, beep once, and went away. I just ordered a mashall electric oil pressure gauge and sender. Going to install prior to going through the hassle of the oil pan and tube. I used one of these on my old b5 a4 and it seemed to work decently.

ECS Tuning-Audi

Not a bad idea.

Below is a thread you should read through that has tons of good information on oil pressure for these vehicles.

1.8t Oil Pressure Survival Guide and troubleshooting DIY

Cheers!

Jason

Prospeeder

Again pressure and volume are totally different. You can have perfect oil pressure and the tube 50%+ blocked off. Reading a gauge is worthless in this case. Typically when I see people do exactly what you are, continuing to drive it and trying to convince yourself nothing is wrong, the turbo wears out and destroys itself, or the rod bearings start wearing thin.