Drainage points b7

[dieselal]

Hi , I have 2011 b7 bluemotion passat . I had engine light show up and the garage read numerous codes and cleared them and all was ok for a week , then after heavy rain the light came back on for a day and now its off again . I popped the bonnet , cleaned out lots of dead leaves and compost like substance from under the passenger side windscreen scuttle and will do the driver side tomorrow , but cant seem to locate the drainage plugs . I am wondering if the heavy build up of debris caused water to get near the ecu , thus throwing up codes and engine light , and cleaning this area out will at least eliminate that from any possible causes , I did the same on my previous car , Audi a6 2002 but just pushed the drain hole bungs through .Does anyone know exactly where I can find these drain holes under the scuttle trim? Thanks in advance

[Crasher]

It doesn’t use the type 3B (B5 in your way) design of plenum chamber to the type 36 (B7) and with the screening doesn’t seem to get filled with water; however the ECU’s seem to suffer corrosion damage and the state some of them are in when removed is a shock. We have seen a few fail now due to water getting inside the case and damaging the board and a clue to this is sensor ref A or B fault codes as these can only be generated by ECU internal failure. Don’t bother trying to get it repaired or tested, every single company I have ever tried for this sort of work is useless and often say something is faulty when it isn’t or, more infuriatingly, the other way around.

[dieselal]

Thx once again )

[dieselal]

Engine codes showing coolant sensor 2 , making it look like radiator fan is blocked but it isnt. I know there are 2 sensors on the cffb engine but which one is most likely the culprit, egr side or thermostat housing side?

[Crasher]

Any chance of posting a full VCDS scan?

[dieselal]

I think my mechanic uses snap on scanner. It has proved successful previously but the engine light is coming on and then resetting itself almost daily. I will change one or both coolant sensors this coming week although the car drives normal and temperature seems stable.

[dieselal]

Garage unable to fit me in til 22/04/22 to replace both coolant temp sensors. I rang Euro car parts and they stock ERA sensors , @£16 each or main ******* genuine VW is £52 each , big difference in price and I am tempted to go for ERA . The engine light was resetting itself after few hrs for about 2 weeks but now its on permanently , although the car drives like normal .Scan showed coolant temp sensor TWO high. Not sure where sensor TWO is located but I would assume sensor ONE is the primary one , that sensor maybe the side of the engine near EGR valve and sensor TWO perhaps someplace near the radiator ? Will be replacing both just to be sure .