1.6 FSI - rough idle

[OrMar]

My A2 is 2002., 212.000 km, starts well (now and there dies after first daily start, but works normaly after restart), drives normaly, I'm using 100octane fuel, fuel consumption is ok, but there is this check engine light, and idle is quite rough. Diagnostics returns errors as in picture, P1020 Fuel pressure regulation, control limit exceeded and P1031 - Intake Manifold Runner Control (IMRC) Valve: target value not reached.

I don't expect 20 years old car to run perfectly, it's fine with me as it is, as it is perfectly usable car, but I wouldn't want to run into some more serious trouble.

So, what is word of advice of the people who know this cars/engine: bother with this, and if yes - what to change ?

Short video of idling, turn on volume to hear

Thanks,
Mario

 

[PlasticMac]

Hi,
The P1031 error indicates that the movable flap in the inlet manifold. Could be a broken vacuum actuator, the linkage, or build up of crud (exhaust soot from EGR, oil condensate from PCV).
Start with a visual check, left hand side of engine, towards the back. Worst case is strip down to remove inlet manifold, and clean flap mechanism.
The P1020 could be the high pressure fuel pump, in tank fuel pump, or fuel filter. Try replacing the filter first.
I'd check the date code on the coil packs, and if they are the originals, replace them with NGK or Bosch. Change plugs, if you haven't already changed them.
Also, look carefully at the fuel cap, as it must seal completely. Any slight leak will cause hesitation when moving off.
Good luck, and let us know how you get on.
Mac.

 

[Clackers]

There are a number of scenarios that will come into play.
cheap scenario is fuel filter, air leak on the manifold(or other points of entry)
expensive scenario Fuel pump, lower intake manifold blocked, actuator broken
First option <£50, second option >£300+
I've had both scenarios in the past, the second option cost me over £700...and still ran like a bag of nails...