I have had Mobil 1 in the car for a week now, after an oil and filter change, and can't help thinking the engine seems noisier. I don't record mpg, but that also seems a little down. Anyone else used this oil and noticed anything different? I thought I was buying the best available for my 1.9 PD

Which specific oil did you use?

In my bike, Mobile 1 is the oil which makes it run best, quieter, cooler and feels livelier.

A PD engine needs special anti scuff, anti wear additives because the camshaft also drives the unit injectors which mean the cam lobes are rather narrow and as a result rather stressed.

I don't know which of the several Mobil 1's you used or even if it is approved to meet the requirements of VAG for this engine

On the container it should say 505.01 for normal 10,000 mile oil changes, or 506.01 for extended "longlife" oil changes.

There is also 507.00 which would also do.

http://www.oilspecifications.org/volkswagen.php

I checked and it is 507.1, it is Mobil 1 ESP 5W 30

sorry I meant 507.00, Exxon Mobil also state it is suitable for 505 01

Then it's the correct oil.

 

Noise can be very subjective. It's getting colder so that could explain MPG being down.

Mpg loss is probably down to winter fuel

I'm running Mobil1 504/507.  It's no noisier than any of the previous oils I've had.  In fact, it's running so smoothly I've been trying to work out how to reduce the idle speed 50-100rpm.  Fuel economy is good too.

 

This is a TSI engine, not diesel.