I have a 98 2.8 Q with Tip. 1 month old, 1500 miles. I have problem involving reverse and what feels like either a surge in power, or a total lack of power. This happens 75% of the time, the balance no problem. Normally backing on an incline but sometimes on flat.<p>Also have a problem with low speed acceleration and what feels to be a power shift or search to each wheel. Dry level pavement. Dealer has replaced ECU, which helped for 4 days, then back to same symptoms. Any advice ?<br>