AUTOOL PT620 Digitales Motoröldruckprüfer-Set

Easy to use, and the display is clear when checking engine oil pressure. A handy tool to have in the garage.

This worked very well for trying to get a handle on the common Audi 2.0t low oil pressure issue (B8 series A5 in this case). Since these cars often develop low oil pressure warnings at low rpm with a warm engine, I thought I’d share our results.
I wanted a device that would log the lowest pressure while driving so we could see what happened to trigger these car warnings and see if the pressure was really low enough to be a major concern. These cars don’t have pressure sensors, only low pressure warning triggers for the alert, so no way to see pressures without an external gauge such as this.

I did not see many options for a reasonably priced alternative that was available fast so I rolled the dice and ordered this oil pressure test kit even though it had few reviews and most of them were Vine sponsored. The thing showed up less than 12 hours after ordering which was great. Always a little suspicious of Chinese goods I was pleasantly surprised to find the build quality of the device, packaging, and adapters all looked quite good. No rough threads or questionable milled bits. On mine the hose with quick coupler fitting and hose came screwed on black threaded sensor right out of the box. The quick coupler was well made and seemed secure enough when attached to an adapter to be ok taped to the engine while driving around a bit.

One thing to note, the adapter assortment is vast, but they are not labeled with the thread spec, so it’s necessary to verify what the car has. In our case I knew we needed an m10x1 thread, which turned out to be the #1 adapter and also the first on the printed list that came in that box. The adapters are numbered 1-16, but the printed list of sizes included is not numbered. It may be that the list is in numerical order that it matches the adapter numbers, but I can’t confirm. I included a picture of the list in my review.

We removed the upper oil pressure sensor from the car, screwed in the #1 adapter that matched its threads, and then connected the quick coupler. I just put a jumper wire in the cars sensor plug to ground so the car would not constantly beep at us during the test. A tee adapter would allow for use of both this and the car sensors at the same time, but we did not have one yet so we just went for it.

The wire from the unit’s sensor was long enough to run up across the engine, out under the rear edge of the hood, and into the passenger side window so we could monitor it in real time while driving.

Bottom line, once we figured out the interface buttons, it worked great and confirmed we did have adequate oil pressure at idle when warm, which we deemed sufficient for idle speed (though below audi specs) and immediately rises above idle, topping out at the car’s relief valve pressure of about 51-52 psi. There is about a second or so of latency between pressure changes and the display reading shift, but it’s a nice window into the engine pressure and range.

Worth noting it works a bit like a weight scale in that holding down one of the buttons recalibrates to zero, which you don’t want to do with it hooked up and car running or actual pressure becomes zero on the display. A short tap of the same button instead of long hold resets the high and low recording to zero without resetting the calibration. This is crucial for lowest pressure log since it will start at zero before you turn the car on! So after starting the engine you’ll want to tap that button to zero out the pressure high/low without changing the baseline calibration to zero. Took us a minute to figure that all out. It’s a good device which I can recommend.

The rest of this review only pertains to other Audi 2.0t engine owners in case they are in the same boat. We were dealing with this plus usual bad piston ring design oil consumption issue. We used this tester after tearing the engine down to replace pistons and timing chains. We removed all the stupid oil screens, decided the cam journals and balance shaft bearings were ok, and the oil pump had been replaced already so we kept it. We installed new Wossner pistons that use factory 21mm connecting rod pins and rods, but have proper wide waffle oil control rings. This totally solves the oil consumption and black oil too! We did leave the two stage oil pump in high pressure mode by not connecting the wire near the sump that allows it to shift into low pressure mode at lower revs. But we still get low pressure at warm idle, just not catastrophically low. Maybe 13-15 psi. It instantly jumps up above 20 psi above idle and is linear with revs up to 51 psi limit. Not sure where the oil pressure leakage is that is still haunting us, but seems fine to drive for now. Possibly intake cam phaser. I’ll try to post a YouTube video on this whole deal soon. Will update this review with what to look for if I do.