Citroen P0121

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Mitch1502
Posts: 4
Joined: 23 May 2022, 08:19
Location: London
My Cars: Currently own
----------------------
Citroen C4 coupe vts (2.0l petrol)
1986 land rover 90 (300tdi)

Owned
------------
Clio sport
Standard clio
Subaru legacy
Subaru Impreza WRX
Alfa Romeo 147
3 Ford's
2 Vauxhall's
Mgf
Renualt Laguna couple
Peugeot 208

Citroen P0121

Post by Mitch1502 »

Afternoon all,

I was wondering if anyone had any advice just bought myself a 2008 2l Citroen C4 vts and was running perfect until on the way home came up with service and engine management warning.

I got home and put the code reader on it and came up with code p0121 (Throttle Position Sensor) before I look any further I was wondering if anyone here had any advice about common causes before I start looking into it

Any help would be great
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GiveMeABreak
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Re: Citroen P0121

Post by GiveMeABreak »

Basically it means the data from the throttle sensor tracks (1 & 2) is incoherent. The data on tracks 1 & 2 are constantly compared with each other to ensure they are reading the position correctly. If there is an issue between each of them then this fault is returned.
Please Don't PM Me For Technical Help

Marc
Mitch1502
Posts: 4
Joined: 23 May 2022, 08:19
Location: London
My Cars: Currently own
----------------------
Citroen C4 coupe vts (2.0l petrol)
1986 land rover 90 (300tdi)

Owned
------------
Clio sport
Standard clio
Subaru legacy
Subaru Impreza WRX
Alfa Romeo 147
3 Ford's
2 Vauxhall's
Mgf
Renualt Laguna couple
Peugeot 208

Re: Citroen P0121

Post by Mitch1502 »

Hi thank you for the information and the breakdown so is it normally the sensor that goes?
User avatar
GiveMeABreak
Forum Admin Team
Posts: 36996
Joined: 15 Sep 2015, 19:38
Location: West Wales
My Cars: C3 Aircross SUV HDi Flair Peperoncino Red (The Chili Hornet)
C5 X7 2.0 HDi Exclusive Mativoire Beige (The Golden Hornet)
C3 1.6 HDi Exclusive Aluminium Grey (The Silver Hornet)
C5 MK II 2.0 HDi Exclusive Obsidian Black
C5 MK I 2.0 HDi SX Wicked Red
Xantia S2 2.0 HDi SX Hermes Red
C15 Romahome White
XM 2.0 Turbo Prestige Emerald Green Pearlescent
XM 2.0 Turbo Prestige Polar White
XM 2.0 SX Polar White
CX 20 Polar White
GS 1220 Geranium Red
CX 2.4 Prestige C-Matic Nevada Beige
GS 1000 Cedreat Yellow
x 5644

Re: Citroen P0121

Post by GiveMeABreak »

It depends on what system you have. Pop your VIN up (automasked on post submission). Most later vehicles over the last 20n years or so have the TPMS built into the accelerator pedal, so it's a new unit. If you have this system, I'd make sure the wiring is ok and hasn't been damaged bear the connection. They can and do wear out though over time.
Please Don't PM Me For Technical Help

Marc
Mitch1502
Posts: 4
Joined: 23 May 2022, 08:19
Location: London
My Cars: Currently own
----------------------
Citroen C4 coupe vts (2.0l petrol)
1986 land rover 90 (300tdi)

Owned
------------
Clio sport
Standard clio
Subaru legacy
Subaru Impreza WRX
Alfa Romeo 147
3 Ford's
2 Vauxhall's
Mgf
Renualt Laguna couple
Peugeot 208

Re: Citroen P0121

Post by Mitch1502 »

Awesome thank you for that the vin is VF7**************[VIN obfuscated, can be read by forum staff]
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GiveMeABreak
Forum Admin Team
Posts: 36996
Joined: 15 Sep 2015, 19:38
Location: West Wales
My Cars: C3 Aircross SUV HDi Flair Peperoncino Red (The Chili Hornet)
C5 X7 2.0 HDi Exclusive Mativoire Beige (The Golden Hornet)
C3 1.6 HDi Exclusive Aluminium Grey (The Silver Hornet)
C5 MK II 2.0 HDi Exclusive Obsidian Black
C5 MK I 2.0 HDi SX Wicked Red
Xantia S2 2.0 HDi SX Hermes Red
C15 Romahome White
XM 2.0 Turbo Prestige Emerald Green Pearlescent
XM 2.0 Turbo Prestige Polar White
XM 2.0 SX Polar White
CX 20 Polar White
GS 1220 Geranium Red
CX 2.4 Prestige C-Matic Nevada Beige
GS 1000 Cedreat Yellow
x 5644

Re: Citroen P0121

Post by GiveMeABreak »

Hi, yes your accelerator has the throttle position sensors in the pedal on this model.
Please Don't PM Me For Technical Help

Marc
Mitch1502
Posts: 4
Joined: 23 May 2022, 08:19
Location: London
My Cars: Currently own
----------------------
Citroen C4 coupe vts (2.0l petrol)
1986 land rover 90 (300tdi)

Owned
------------
Clio sport
Standard clio
Subaru legacy
Subaru Impreza WRX
Alfa Romeo 147
3 Ford's
2 Vauxhall's
Mgf
Renualt Laguna couple
Peugeot 208

Re: Citroen P0121

Post by Mitch1502 »

Hi

Thank you for this
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