2011 Skoda 1.8 TSI with a loose chain and oil pressure and cam codes

I just bought a second hand 2011 Skoda Suberb 1.8 TSI with 190K kilometers on the clock. Same engine as the Audi A4. It was a trade in and the dealer was selling it for half book so I knew to look for problems. I have some history, but in short the garage they took it to replaced the plugs, two coils, the lower oil pressure sensor, flushed the oil and filled with 15-w40. They wrote on their report that it might need a new engine.

Basically, after doing my own checks I bought it cleared the codes and started driving home about 1 hour 30 minutes, half city half highway. During the drive I got the following codes:

P164D Reduced Oil Pressure Switch: malfunction

P0341 Camshaft Pos. Sensor Circ. : range/Performance

Freeze frame data showed the first code 49 times and second one 68 times. Oil pressure warning on the dash went on and off intermittently mostly while in traffic. Had some other similar related codes in the freeze frames but only in the single digits.

When I checked channel 93 it showed 93-3 Phase Position Bank 1 Intake at +11.73 degrees. I understand that spec is +/-5 degrees. That pretty much verifies to me that the chains are loose as all heck. I’m actually surprised the cam hasn’t jumped and blown up the engine.

Logically it seems pretty straight forward to me that the codes are related to the loose chain. Mostly I just want to verify my conclusions with people who are familiar with this engine and it’s problems before and I start pulling the engine apart to put in the new tensioner and timing set.

EDIT 23/06/21

So I also ran across this post regarding the oil filter post being a problem. Not sure if it’s relevant since it’s a 1.8 TFSI and these engines seem to have different oil cooler / return designs depending which vehicle they’re installed in.

So here’s an update. I found channel 159 which has the status of the two oil pressure sensors. For those who don’t know, there are two switches mounted on the housing right below the oil filter, the low pressure switch and high pressure switch. LP switch is closed ( 1 ) when the oil pressure is above the low pressure threshold. HP switch is closed ( 1 ) when oil pressure is above the high pressure threshold.

It doesn’t look like the dealer’s garage changed the oil filter after doing the engine flush, new filter isn’t listed on the bill of goods and the filter doesn’t look new, they just changed the oil to 15-w40. Also from a service a few months ago it says they need to order a new electric oil valve… Don’t know why or if they ever did replace it. Not sure if the one in the link is the same as the one on my engine. Lot’s of variations…

So from a cold start at 20C both switches close during starting. Then just the LP switch is closed till the oil temperature reaches about 78C. Then the LP switch starts opening and closing. Around 82*C it’s staying mostly open. If I slowly bring the RPMs above 1000 the LP switch closes. Once the temps get into the 90’s I have to get above 3500 rpm to close the HP switch. Was able to trigger the P164B and the cam shaft phase errors.

So there is definitely an oil pressure problem. Seems to be in it’s early stages though and still moderate, like slightly below spec would be my guess although wouldn’t know exactly unless I hook up a gauge.

So the big question here is what is the root cause… I found this: 1.8t Oil Pressure Survival Guide: Oil Pressure Warning Light diagnosis and troubleshooting. It’s an earlier version of the engine, but looks worth reading nonetheless. Going to read it now and see if it gives me any ideas. Also ran across this video which seems to blame the bad tensioner for low oil pressure since the oil pump chain is run off the same sproket as the timing chain. Lot’s of directions to look at and need to find a methodical approach to this…