I'd be interested to know if anyone has done this to a SE or later car and claim an improvement.

Reason being VAG switched from MAF to MAP based smoke maps on later cars

Well I did mine this evening, just chucked a load of grease on the end of the disconnected plug then plugged/unplugged it several times to "clean" the contact patch. Then some more goop on the end and repeat, until I had enough for one last application that went on and got pushed all the way home. If that doesn't make any difference I'll use another sachet of grease and pack the socket end instead, but I couldn't get my hand in properly tonight without keep burning myself on whatever the metal thing is on the side of the block (maybe oil pump, I can't remember).

For anyone thinking about doing it but doesn't have silicone grease, just put the plug on and off several times and see if that makes a difference, it's more likely to be this which actually makes a difference to the running of the engine anyway as it should remove any corrosion, the grease is just to keep things clean once you've done that. I've only just filled up (about 40 miles ago) so I'll be looking for any improvements in real-world MPG as well as performance

This morning, my engine appeared to idle more smoothly. In the past when sat at idle (say, at a junction, so generally clutch in, in gear, brakes off, ready to move off) there's been a slightly annoying and irregular vibration through the car, almost like the engine is misfiring but much less violent. This morning, I didn't notice it at all. Whether it's a coincidence or actually related to this, I don't know, but so far things seem to be going alright.

I did this a long time ago.. at the time seemed to improve the idle and pull... but, I dunno.. I'm a bigger believer that it's way more related to the connection being broken and re made a few times... like crackle on a volume control.

Word of warning.. don't go to mad with the stuff (like I did)... because that sodding plug will refuse to go back on due to the grease causing an air tight seal and back pressure forcing the plug back...

I reckon a pea sized blob over each contact slot on the plug would be enough..... or a tooth paste style squirt across the top of it.

Edited 24 May, 201214 yr by Rob.