Tata Tiago XZ (2019) Petrol: Sudden Loss of Acceleration / Limp Home Mode. Spent ₹20k+, the issue keeps coming back! Need help

Hi everyone,

I am facing a highly frustrating and dangerous issue with my 2019 Tata Tiago XZ (1.2L Petrol), and I am completely stressed out.

The car randomly loses all throttle response while driving—especially on high-speed highways. The accelerator pedal goes completely dead, the RPM needle freezes near idle (around 1,000 RPM), it refuses to rev ("stop taking the race"), and the Check Engine Light pops up on the dashboard. It forces the car into a strict Limp Home Mode.

The worst part is that the issue is completely intermittent. Sometimes it happens twice in one day, and sometimes it doesn't return for 15 days, making it incredibly hard for mechanics to catch.

I have faced this issue 4 separate times and have already spent over ₹20,500, but nobody has actually fixed the root cause:

1. 1st Time (Local Garage): They connected an OBD scanner, simply erased/cleared the fault code, and charged me ₹700. The car ran fine for a couple of days.
2. 2nd Time (On Vasad Highway): Broke down with family. A local highway mechanic misdiagnosed it as a firing issue, replaced all the spark plugs, and charged me ₹8,000. It failed again 15 days later.
3. 3rd Time (Authorized Tata Service Center): Took it to Tata. They did a standard paid service, changed the oils, cleaned the throttle body, cleared the error code, and handed me an ₹11,000 bill.
4. 4th Time (On Bardoli Highway): Stalled again on a busy highway with my family stranded. Out of emergency, the nearest Bardoli workshop just did a quick scanner reset to clear the code so we could reach home safely.

The car is now back at a Tata Service Center in Surat. Because the car is running fine today, they want me to come for a test drive to "show them the issue" because no active code is showing up on their scanner right now. From what I’ve researched, cleaning a throttle body only works for mechanical stickiness, but sudden highway drops point to an internal electronic sensor failure (TPS/Potentiometer mismatch) or loose wiring harness pins/couplers.

Has any other Tiago or Tigor owner faced this specific intermittent limp mode issue? Did replacing the entire Electronic Throttle Body Assembly solve it for you permanently, or was it a wiring harness/pin tension issue?

I am terrified of spending another ₹10,000 on a new part only for the issue to return on the highway. Any advice or guidance would be highly appreciated. Thank you!