I am new to this forum, thank you for giving me the forum to share my experience. I am not a mechanic, this is my first post and wondered if anyone can please help me resolve this problem.
Background
VW Golf 51 plate 1.6SE petrol, full service history, lost power on motorway STOP came on display (as best as I can recall) car came to a standstill. This followed a prior period when the car engine revs were erratic, going up and down between 800 & 1200 whilst the vehicle was idle.
I took the car into a garage, they decided to replace EGR valve and fit new breather tube (I think that's what it's called).
Drove car away, Emissions workshop light came on with error code: 16786 EGR system excessive flow PO402
Garage reset code but light kept coming back on.
Vehicle examined by an auto electrician, no fault found but told to check valve timing, four gas test and cat. convertor. All of above checked and fine although vehicle was showing a problem with four gas test which I was told would have meant mot failure so we agreed to replace the front Lambda sensor.
Computer reset, drove car away... emmission workshop light came back on. Computer reset, same error code.
Garage cleaned air manifold, throttle body and replaced new seal around air manifold (hope I'm explaining this clearly) also cleaned air inlet manifold.
Problem still persists despite code even being cleared by my local VW dealer as a gesture of goodwill. (I was thought it might have just been a software / ecu reset fault).
For some reason, (and we have no logic to support this), we are (next week) planning to replace the MAP sensor.
Question - Please can anyone shed any light on what this problem might be? The vehicle has 84k miles is fully serviced, maintained and in excellent condition. I am pulling my hair out now as the garage are unable to pin point the problem and I am worried I am just throwing money away now.
Please, can anyone help?
