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Discussion Starter #1
Hello, for the past few weeks I have been thrown a p1120 error code and my car jumps into limb mode.
Well, I did some research on this forum, found some saying I should swap the throttle body out.

Then I did some car specific searching on Autodoc and found a Bosch TB with the part number: F 01C 600 027.
BUT it's around 460£ new.

I decided to check/clean the TB I have on the car now and found another part number on the TB. This number is 0 280 750 137 and is also Bosch.
But this one is around 115£ new.

Does anyone know the difference? Which one should I pick?
And anything I should be aware of when changing the throttle body?
 

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P1122 code relates to throttle (pedal) position sensor so before you go spending a lot of money check the sensor which will be near the top of the accelerator pedal. Clean the contacts and make sure the connector is secure. Try it and see if that works. A new sensor is about £25 and is basically a potentiometer, and that is a cheaper option. See if that works. Then before you swap over with a new throttle body get it plugged into a fault reader that goes deeper into the problem than a cheap dongle and free app.
 

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Discussion Starter #3
P1122 code relates to throttle (pedal) position sensor so before you go spending a lot of money check the sensor which will be near the top of the accelerator pedal. Clean the contacts and make sure the connector is secure. Try it and see if that works. A new sensor is about £25 and is basically a potentiometer, and that is a cheaper option. See if that works. Then before you swap over with a new throttle body get it plugged into a fault reader that goes deeper into the problem than a cheap dongle and free app.
I just tried to clean the contacts and securing the connector. I tried going on a drive and it actually seemed to have helped a bit, but when I gave it max throttle it threw me into limp mode again with the same error message. When I drove the car before I cleaned/secured it, it would immediately go into limp mode on about 50% throttle. So it did help a little, but still have the problem :/
 

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Well I'd try a new position sensor next as it is a cheaper option. I've not taken one apart but if it is the same as other potentiometers that I have then there are three connections and one of them goes to a wiping arm and contact on a resistance wire. If either the wiper contact or wire are damaged/contaminated the expected voltage(s) by the ecu will be in error and that will throw up the code.
It may have four connections, the fourth connects to the wiper at a resting position which I presume is for when the engine is idling.
Then again it could have six pins so there are two sensor paths. I wonder if they disagree that could produce an error message. From what I've found it is six pin. See links in a later post.
 

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Discussion Starter #5
Well I'd try a new position sensor next as it is a cheaper option. I've not taken one apart but if it is the same as other potentiometers that I have then there are three connections and one of them goes to a wiping arm and contact on a resistance wire. If either the wiper contact or wire are damaged/contaminated the expected voltage(s) by the ecu will be in error and that will throw up the code.
It may have four connections, the fourth connects to the wiper at a resting position which I presume is for when the engine is idling.
Then again it could have six pins so there are two sensor paths. I wonder if they disagree that could produce an error message.
Do you know where this is located on the Giulietta? on the pedal or on the throttle body?
 

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A fly-by-wire system has tps on the pedal (post #2). The throttle body then has a motor to operate the butterfly. If it has a throttle cable the tps would be on the side of the throttle body and is operated when the cable opens the butterfly. What have you been cleaning?
Does it look like this one? This is for RHD, is yours LHD? If so may be different.
 

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Discussion Starter #7
A fly-by-wire system has tps on the pedal (post #2). The throttle body then has a motor to operate the butterfly. If it has a throttle cable the tps would be on the side of the throttle body and is operated when the cable opens the butterfly. What have you been cleaning?
I have cleaned the plug contacts on the pedal and the throttle body itself
 

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Discussion Starter #8
A fly-by-wire system has tps on the pedal (post #2). The throttle body then has a motor to operate the butterfly. If it has a throttle cable the tps would be on the side of the throttle body and is operated when the cable opens the butterfly. What have you been cleaning?
Does it look like this one? This is for RHD, is yours LHD? If so may be different.
Yup, it does look like that but mine is LHD. Do you recommend I change the whole unit?
 

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If you can get one. I've seen a breakers located in the Netherlands that sells second-hand spares. I think it was on eBay that I saw them. From what I can gather from images of those for sale in Italy and Lithuania the difference is the way the pedal is cranked. You need the number on the TPS to see if it is universal to all the Giulietta engines. It is used in a large range of Fiat, Lancia and Alfa Romeo vehicles. It does look as though the TPS is held on to the pedal with screws so you could buy the whole assembly to get the sensor.
 

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Discussion Starter #10
If you can get one. I've seen a breakers located in the Netherlands that sells second-hand spares. I think it was on eBay that I saw them. From what I can gather from images of those for sale in Italy and Lithuania the difference is the way the pedal is cranked. You need the number on the TPS to see if it is universal to all the Giulietta engines. It is used in a large range of Fiat, Lancia and Alfa Romeo vehicles. It does look as though the TPS is held on to the pedal with screws so you could buy the whole assembly to get the sensor.
Thank you! I found the whole pedal unit on Autodoc, is a calibration necessary when installed?
 

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The only time I've heard of it having to be calibrated is if the ecu map has been altered. If it does Fiatecuscan/Multiecuscan should do it.
 

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Discussion Starter #13
Just took it for a drive, it also goes into limp mode when controlling speed using cruise control.. hmm
 

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You'll need to get into the footwell with the replacement ready to compare and see what tiype of fastenings are used, e.g. circlips, split pins, nuts or star washers. Hopefully someone who has done this to help, otherwise you will have to wing it!
 
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