Exclusive! Chevrolet Tavera recall – the inside story
The main reason for the recall of 114,000 Taveras by GM India last month for irregularities in exhaust emission tests can be traced back to 2003-2004 when the company was gearing up for the move from BSII to BSIII emission standards.autos Updated: Sep 24, 2013 12:19 IST
The main reason for the recall of 114,000 Taveras by GM India last month for irregularities in exhaust emission tests can be traced back to 2003-2004 when the company was gearing up for the move from BSII to BSIII emission standards.
According to company sources involved at the time, GM had two options to upgrade the Tavera’s then 2.5 litre Isuzu engine to the new emission standards that came in to effect on April 1, 2005. One route to meet the emission norms was with a decent safety margin of around 30 percent but this involved upgrading the fuel-injection pump, which was a costly component. However, BSIII could also be met by improving the ‘after treatment’ with a better catalytic converter and without changing the fuel pump. This would save the company approximately US$ 1700 per car and not surprisingly, GM chose to take the less expensive route to BSIII
But, by using the older fuel pump the ageing Isuzu just about scraped through to BSIII with approximately just a 15 percent margin for error. That wasn’t the issue because meeting emission norms is a straightforward pass or fail test and it doesn’t matter how much you pass by.
But being on the borderline of the latest emission there was very little margin for error and hence GM had to ensure that the engine was produced with tighter controls and tolerances because variations in manufacturing could (and did) result in variation in emissions too. With a small margin for error it’s likely that if emissions varied substantially the Tavera would fail to meet the norms. Over time, manufacturing inconsistencies crept into Tavera production and this meant that some batches of Taveras didn’t actually meet the BS III standards.
Now here’s where it gets murky. GM engineers were reportedly aware of that some Taveras were not meeting the norms and would dodge the Conformity of Production (COP) audit by making available pre-tested, BS III-compliant engines to the inspectors. There was also allegedly another form of manipulation, by which certain variants of the Tavera were wrongly counted in a higher weight class in order to be able to face more lenient emissions standards.
GM itself has reported this issue to the authorities in a three-page letter which is a shocking admisssion of the complicity of certain employees in this skullduggery. GM has sacked several employees particularly those involved in the powertrain and engineering departments as what the company says is an action of its world wide integrity policy.
What’s puzzling the industry is why GM on its own accord escalated the Tavera’s emission saga. The company claims that like a good corporate citizen it wants to come clean and take action against those involved in this debacle. However, there is a view that this letter, which was drafted by lawyers, is a pre-emptive safeguard against public interest litigation or law suits that may arise in the future.