C4 potential turbo/cruise issues

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Cittob
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Joined: 11 Jul 2020, 15:31

C4 potential turbo/cruise issues

Post by Cittob »

Hi all,

Newbie to the forum here,

I wanted to reach out and see if anyone else has any ideas. We have a C4 grand Picasso 2014 and overall it has done exactly what we needed and wanted from a car. Recently I have noticed when the turbo kicks in it doesn't seem to have the power it used to have, there are no odd noises or rattles suggesting the turbo has gone just to mention.

Fast forward to today and the cruise control is behaving a little odd, when you engage it and for example jump it up from 50 to 60 it starts climbing but when the turbo assists it then just clicks off the cruise control abruptly, almost like it isn't gaining the speed it needs in a certain amount of time so just clicks off.

Any ideas or things to check out would be really appreciated, the engine looks like a bit of a nightmare to access anything.

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GiveMeABreak
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Re: C4 potential turbo/cruise issues

Post by GiveMeABreak »

You'll find that if there is a problem with the air / fuelling or other issue, the engine management will deactivate the cruise control until the engine is switched off and restarted.

You really need to get it diagnosed with Diagbox and list any fault codes you are getting. There will probably be a fault code or two logged. If you don't have access to a 'Lexia kit' with Diagbox, a dealer will undertake a diagnostic for £60.

Cittob
Posts: 2
Joined: 11 Jul 2020, 15:31

Re: C4 potential turbo/cruise issues

Post by Cittob »

Ok thank you, the cruise only pauses so doesn't fully deactivate but it is definitely at the time the turbo is engaging to build up the power

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GiveMeABreak
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Re: C4 potential turbo/cruise issues

Post by GiveMeABreak »

Yes, it's a safety issue, if the engine ECU detects any issue with the power / or hesitation, the cruise is the first thing to get switched off.