C4 grand picasso trouble codes

[14c4picasso]

Hi everyone,
Brought a very cheap 07 plate c4 grand picasso to use as a van from copart's yesterday.
Main job is to replace passenger wing/fender.
I haven't driven it yet but after its been idling for a few minutes the dash starts bleeping with a error warning one after another, I've done a scan on the car and it comes up with the following codes;
P1351 preheating plugs never supplied
P0490 EGR opening to small
P1459 EGR stuck open while driving
P0401 air measures higher than setting.
If I clear the codes it will run fine for ages but as soon as I turn it on after a few minutes all the codes come back all at the same time.
I would be really grateful if anyone could suggest what I start looking at first.
I dought it's anything to do with glow plugs as one code mentioned as it starts fine, also I wasn't using a lexia but a half decent other brand device so the explanation of codes might also be wrong?
Many thanks in advance Joe

[RichardW]

eGR valve, might just be sooted up, but could equally be busy. Worth a shot to take it out and clean it, it's not the easiest to get at though if it's a 1.6

[14c4picasso]

Thank you for your reply Richard,
It is the 1.6, do you know if the metal pipe is removed or left on the egr whilst removing? As I read somewhere if it is taken off its almost impossible to get it back in.
Regards Joe

[moizeau]

If this is the 16v 1.6 hdi, the air filter etc needs to be removed to access it. Also there is a metal pipe connected to the lhs of the egr (as your looking at it from the front). Undo the mounting for the heat exchanger prior to removing and refitting the egr or you can damage the mating flange, if this happens you then need to remove this as well which involves a partial empty of the coolant. It you have Diagbox you can do an actuator test to confirm it's knackered and the same again which the replacement prior to fitting to confirm it is the egr at fault and not wiring or another issue.