406 hesitates

It sounds like something connected with the fuel injectors and or it's management system. If it is it will be costly and unfortunately usually can only be dealt with by Pug specialists. Peugeot one day will build good petrol engines, but that day has yet to come. When mine played up it cost over £200+ that's for a V6 though. It was mainly labour. A good full day.

it sounds like the egr valve is not operating correctly needs diag 2000 diagnosis at pug dealer to confirm

"user498" wrote: > My 2 litre 406 GTX auto has just started to idle rough. Its > also lumpy at a > cruise speed, ie with little throttle. If I floor the pedal it > clears until > i back off to cruise again. It will drive like that for about > a mile then > that nice little engine light comes on in the dash and it runs > smooth. > Any clues? Mal

Hi, There should be a fault code entered into the ECU following the engine light illumination, so a read of the codes should give you a start. However the list is long of all the possible cures. The first reply from Peugeot dealers will probably be to replace the coils assy , whether it needs it or not, and if they do it iwill set you back £220 for parts and labour!

If you fancy DIY the following list is taken from the link below

Cuts out Misses:- Check Secondary Ignition System Check Fuel Pressure Check IAC Motor Operation Check The Minimum Idle Air Flow Check EGR System Check For Oxygen Sensor Switching Check PCM Power And Ground Circuits

Hesitation:- Check Secondary Ignition System Check Engine Vacuum Check Fuel Pressure Check ECT Sensor Calibration Check TPS Calibration Check MAP Sensor Calibration Check IAT Sensor Check IAC Motor Operation Check The Minimum Idle Air Flow Check EVAP Emission System Check EGR System Check For Oxygen Sensor Switching Check O2 Sensor Heater Check PNP Switch Check PCM Power And Ground Circuits

Most results seem to be got from changing coils and cleaning/replacing IAC motor (idle control valve)