Posting mostly in case this is useful for someone in the future. I've seen some mention of this online for different models with similar engines and thought I'd try make a record of it in case it happens to someone else here. I have a pretty early model Ibiza mk6 I think as it was a dealer car imported for the launch of the model but it is low mileage (~55,000km).
I had to replace the throttle body on my 2017 1.0 TSI 115hp Ibiza recently due to the internal spring failing. Issue started with the EPC light, a Start / Stop error message, and reduced power. Check engine light also came on while I was investigating the issue. It wouldn't rev over 1500 rpm and idled terribly, sounded like it was constantly at risk of stalling, seemed like it was misfiring. First bit of trouble I've had with the car.
Had an OBD reader so checked the codes, came up with:
P0638
Throttle actuator control (TAC), bank 1 - range/performance problem
02737
P155800: Throttle valve drive, Electrical error in circuit.
No misfiring codes.
Had a look around here and other forums online for same engine and throttle body failure seemed to fit the description. I checked the obvious stuff I could like electrical connections and all seemed OK.
Other people had an issue with the spring failing in the throttle body, and you can check that by taking the ducts off which are just clipped on and trying to move the butterfly valve. You don't even have to remove the part fully to test this, just unplug the electrical connection and detach the duct. If you can rotate the butterfly valve and it springs back into place, the spring hasn't failed. If it moves but doesn't spring back to the default position, there's a problem with the spring.
Best explanation showing the failed butterfly valve and guide for how to install the part was this video: Vw/Seat/Skoda/Audi loosing power throttle body faulty Code p155800/p023800 diagnostic and repair
If you want to see inside and what the failed spring looks like, this video isn't the exact same engine but the throttle body is very similar: VW GOLF 7 1.2TSI THROTTLE BODY PROBLEM?. I took my failed throttle body apart and can confirm the spring looked and failed in the same way. Not sure you can get the spring itself off the shelf, the gent in that video had a new spring fabricated for him locally.
I bought the same model Magneti Marelli part online for less than half what the dealer was quoting, without the VW OEM badge on it of course. OEM number: 04C 133 062C. Cost just over €200 with shipping.
The installation is very straightforward, a few clips either end for the duct and 3 screws. Might need to unclip some hoses which are attached to the duct as well, and unplug the electrical connectors of course. I didn't replace the gasket, partly because I couldn't find one available and partly because it looked ok. Maybe something worth considering changing as well.
I don't know whether this is required or not, but I did a throttle body alignment with the Car Scanner app and the OBD reader I had. You don't need OBD Eleven or the dealer diagnostics tool to do that. Think I paid 4 quid for the pro version of the app for a few months just to do that, but it was easy and it worked.
Clear the DTCs, did the throttle body alignment, restarted the car, and worked perfectly. No issues so far.
Bit of a wall of text there, but hopefully it's helpful to someone! Not a difficult job and saves a good bit of money doing it yourself.
I had to replace the throttle body on my 2017 1.0 TSI 115hp Ibiza recently due to the internal spring failing. Issue started with the EPC light, a Start / Stop error message, and reduced power. Check engine light also came on while I was investigating the issue. It wouldn't rev over 1500 rpm and idled terribly, sounded like it was constantly at risk of stalling, seemed like it was misfiring. First bit of trouble I've had with the car.
Had an OBD reader so checked the codes, came up with:
P0638
Throttle actuator control (TAC), bank 1 - range/performance problem
02737
P155800: Throttle valve drive, Electrical error in circuit.
No misfiring codes.
Had a look around here and other forums online for same engine and throttle body failure seemed to fit the description. I checked the obvious stuff I could like electrical connections and all seemed OK.
Other people had an issue with the spring failing in the throttle body, and you can check that by taking the ducts off which are just clipped on and trying to move the butterfly valve. You don't even have to remove the part fully to test this, just unplug the electrical connection and detach the duct. If you can rotate the butterfly valve and it springs back into place, the spring hasn't failed. If it moves but doesn't spring back to the default position, there's a problem with the spring.
Best explanation showing the failed butterfly valve and guide for how to install the part was this video: Vw/Seat/Skoda/Audi loosing power throttle body faulty Code p155800/p023800 diagnostic and repair
If you want to see inside and what the failed spring looks like, this video isn't the exact same engine but the throttle body is very similar: VW GOLF 7 1.2TSI THROTTLE BODY PROBLEM?. I took my failed throttle body apart and can confirm the spring looked and failed in the same way. Not sure you can get the spring itself off the shelf, the gent in that video had a new spring fabricated for him locally.
I bought the same model Magneti Marelli part online for less than half what the dealer was quoting, without the VW OEM badge on it of course. OEM number: 04C 133 062C. Cost just over €200 with shipping.
The installation is very straightforward, a few clips either end for the duct and 3 screws. Might need to unclip some hoses which are attached to the duct as well, and unplug the electrical connectors of course. I didn't replace the gasket, partly because I couldn't find one available and partly because it looked ok. Maybe something worth considering changing as well.
I don't know whether this is required or not, but I did a throttle body alignment with the Car Scanner app and the OBD reader I had. You don't need OBD Eleven or the dealer diagnostics tool to do that. Think I paid 4 quid for the pro version of the app for a few months just to do that, but it was easy and it worked.
Clear the DTCs, did the throttle body alignment, restarted the car, and worked perfectly. No issues so far.
Bit of a wall of text there, but hopefully it's helpful to someone! Not a difficult job and saves a good bit of money doing it yourself.
