Joe Ledley passed a fitness test to resume in midfield, while there were places on the bench for Ross McCormack and Warren Feeney who were both returning from long-term injury.
City fell behind in the fifth minute when former Bluebird Alan Lee headed a cross back into the danger area and Mark Hudson headed into his own net.
City were level in the 19th minute when Chris Burke made space down the right. His cross was deflected and Whittingham raced in to side-foot his ninth goal of the season.
The Bluebirds were now attacking at speed but their defence still looked flaky under pressure and there were anxious moments as substitute Freddie Sears raced through and then Neil Danns had a sight on the home goal.
It was yet another slow start to a half by City in the second period as they were penned back on defence for ten minutes before managing to mount some attacks.
McCormack replaced Jay Bothroyd on the hour as City looked to use his speed to push back the Palace defenders.
Stern John replaced Lee in the 76th minute and immediately headed over the bar after forcing a corner.
It took a superb sliding tackle by Gavin Rae to stop Sean Scannell giving Palace the lead with seven minutes remaining as play quickly went from end to end.
Feeney replaced Chris Burke in the closing seconds and City had a penalty shout when John brought down Ledley in the area but the referee waved play on.
Both sides went looking for the winner but in a poor match a draw was a fair result.