[font="Verdana, sans-serif"][size="2"][color="#000000"]Hi everyone![/color][/size][/font]

[color=#000000][font=Verdana, sans-serif][size=1]This is a bit off topic as it does not concern my Monde but a problem with the missis's vauxhall signum 1.9 cdti 150,hoping someone maybe able to point me in the right direction with advice>?[/size][/font][/color]

[color=#000000][font=Verdana, sans-serif][size=3][background=rgb(224, 232, 249)]I have a little problem with my missi's car and am hoping someone may be able to point me in the right direction??[/background][/size][/font][/color]

[color=#000000][font=Verdana, sans-serif][size=3][background=rgb(224, 232, 249)]Vauxhal signum 150 cdti 135k, well looked after.[/background][/size][/font][/color]

[color=#000000][font=Verdana, sans-serif][size=3][background=rgb(224, 232, 249)]She was driving on the motorway earlier and the car went into limp mode, she limped home and I decided after checking the swirl flap bar was working ok then the next port of call was the EGR valve, I removed the said piece of junk and found it to be partially seized on the spring side and the actuator pin in the electric side was actually partially seized in! [/background][/size][/font][/color]
[color=#000000][font=Verdana, sans-serif][size=3][background=rgb(224, 232, 249)]I set about cleaning everything up with wd40 and managed to unseize everything relatively easily, refitted it and took it for a drive, the car drove fine and was no longer in limp mode although the engine light is still on>?? I guess I will need to get the fault code removed from the ecu to get rid of the engine light>?[/background][/size][/font][/color]

[color=#000000][font=Verdana, sans-serif][size=3][background=rgb(224, 232, 249)]So...... I am on the test drive and the car is pulling well through the gears but I am noticing that the turbo does not seem to be kicking in for long and infact the boost has noticeably dropped........still there but not as much.[/background][/size][/font][/color]
[color=#000000][font=Verdana, sans-serif][size=3][background=rgb(224, 232, 249)]back home and I removed the turbo boost sensor from the inlet manifold to find it was totally blocked with crud, I cleaned it all off and refitted it, took it for another test drive and found it was boosting better and for a bit longer but still not how I remember it (not drove it for ages!) boosting.[/background][/size][/font][/color]

[color=#000000][font=Verdana, sans-serif][size=3][background=rgb(224, 232, 249)]My question is....[/background][/size][/font][/color]
[color=#000000][font=Verdana, sans-serif][size=3][background=rgb(224, 232, 249)]Cant the boost valve wear out? or partially break down? Is there anything else I can clean up that would affect boost?Could a partially sticking EGR valve cause loss of boost? (obviously not sticking now)[/background][/size][/font][/color]
[color=#000000][font=Verdana, sans-serif][size=3][background=rgb(224, 232, 249)]I had the DPF and ecu command entry removed some months ago also I have just the other day fitted a four hole blanking plate.[/background][/size][/font][/color]
[color=#000000][font=Verdana, sans-serif][size=3][background=rgb(224, 232, 249)]Many thanks,[/background][/size][/font][/color]
[color=#000000][font=Verdana, sans-serif][size=3][background=rgb(224, 232, 249)]Paul.[/background][/size][/font][/color]

These are all mechanical components, so there is no reason that they cant fatigue over time, and begin to sieze.

Have you tried the likes of BG244 and Whynns EGR cleaner to try clean up some of the carbon deposits?

Pretty brave posting a message about the devils car but we'll make allowances this time.

You shouldn't be putting WD40 into the EGR valve. Use carb cleaner for that.

WD40 is a curse upon humanity. People spray the damn stuff everywhere. It's OK for penetrating rust/siezed nuts, but that's pretty much it. It isn't a lubricant - its lubrication properties are very short-lived. After that it just sits there, attracting dirt and filth until the original problem comes back 10x worse than before. Also you should never use it near electrical circuits/PCBs. It will cause soldered joints to swell and break.

Other than undoing rusted/siezed nuts I would not recommend putting that stuff anywhere near your car (even if it is only a Vauxhall!).