Automatic Transmission Control Module problems of the 1997 Mercury Grand Marquis

While driving mil code p0420 set. Ford TSB 03-24-5 indicates pcm reprogramming rather than replacement of catalytic converters required. Despite being within emissions warranty coverage period dealer charged $119 for this work, claiming emissions warranty did not cover this work. Defective programming of pcm to cause the check engine light to come on, requiring a visit to dealer. Can't pass emissions test with light on, should be against the law. In any case the reprogramming of the pcm should have resulted in no charge. This failure resulted in a mandated, due to state emissions testing, visit to dealer and a charge for service to fix a manufacturing defect. The pcm was reprogrammed, according to dealer, and currently light is off. It is very easy to program the pcm to send erroneous codes at any time, especially when out of warranty, allowing the car dealers to create a cash flow they might not otherwise have. This should be illegal!.

Engine shut down completely while proceeding across a busy intersetion, consumer was able to shift into neutral and restart engine while still rolling and continued on,engine check light would stay on, consumer had aarm reman sensor asy-engine elec. Replaced, and also pcm reprogrammed.