Issue with my Celerio AMT: Local mechanic helped me avoid a Rs 70k bill

An authorized dealer with so many resources couldn't correctly diagnose an issue that a local mechanic fixed in a day!

BHPian NT56 recently shared this with other enthusiasts.

We have the first-gen Celerio AMT as a city-beater car in the family. It is being used in a radius of 5 km from home for running errands and clocked just 20k kilometres in 7 years of ownership. Logging down a recent issue that was faced along with a resolution (that might help others)

Issue:

The car started juddering lightly after running for about 10-15 mins. The issue got worse as the temperatures peaked in the summer and the AC started working hard. Once the juddering started the RPM also started fluctuating rapidly at idle and eventually, the engine would stall. The car would still run fine after a cold start for the first few minutes.

Attempted Fix 1:

The car was given to an authorized dealer whose mechanic suspected an issue with the fuel delivery. So he took the following steps sequentially:

1. Cleaned petrol tank
2. Swapped the fuel pump
3. Swapped the ignition coil
4. Swapped the throttle body

None of the above worked and they concluded that this was an engine issue and gave an estimate of 70k for overhauling the engine. This was refused and the car was taken back after 4 days.

Fix:

To get a second opinion a local mechanic was found who had worked on a friend's car before and overhauled the engine. He suspected an electrical fault and was very confident that it isn't an engine issue.

He changed the spark plugs, ignition coil and MAP sensor. He claimed the car was scanned and it was showing the MAP sensor error. He fixed the car in a single day and it's running smooth now!

The root cause is suspected to be the MAP sensor which was giving faulty feedback to the ECM and that in turn was cutting the power to the engine prematurely.

Note:

I am surprised that an authorized dealer with so many resources and technical expertise wasn't able to correctly diagnose the issue that a local mechanic fixed in a day! I don't think it was a case of deliberate misleading but rather just the incompetency of the authorized garage.

Check out BHPian comments for more insights and information.