Jose Mourinho's men looked set to repeat the slim Premier League victory they earned at City last season after Pablo Zabaleta was sent off and Andre Schurrle netted following a brilliant counter.
But substitute Lampard ensured it would end honours even between the two title contenders as he netted acrobatically late on.
Lampard, who scored 208 goals in 626 games for Chelsea before departing in July, had his name sung by the visiting fans following his introduction in place of Aleksandar Kolarov late in the second half.
Those tributes were soon replaced by silence, however, as the 36-year-old, who is on loan at the Etihad Stadium from New York City, grabbed a deserved equaliser for the 10-man hosts.
The goal ended Chelsea's 100 per cent start to the league season, and Mourinho will rue the missed opportunity to have gone eight points clear of arguably their fiercest rivals.
Manuel Pellegrini took the surprise step of handing Eliaquim Mangala something of a baptism of fire. The Frenchman made his debut in place of Martin Demichelis as one of four changes from Wednesday's defeat to Bayern Munich.
Diego Costa's hamstrings held up enough to see him lead Chelsea's line, bumping Didier Drogba back to the bench after a lacklustre show in their UEFA Champions League draw with Schalke.
The Spain striker's first contribution to the contest was a full-blooded 50-50 with Vincent Kompany that saw him come off second best after Yaya Toure had forced the first save of the game out of Joe Hart.
Though Cesc Fabregas and Nemanja Matic's influence in midfield increased, the visitors were unable to completely stem the flow of City attacks and were fortunate to see Fernandinho fail to properly connect with Aleksandar Kolarov's cut-back and Sergio Aguero half-volley an Edin Dzeko knockdown over the crossbar when he might have done better.
But neither side could find a breakthrough before half-time, despite Aguero and Costa getting brief glimpses at goal just prior to the break.
Mourinho will undoubtedly have called for more from his players during the interval, but City picked up where they left off following the restart.
Aguero tested Thibaut Courtois early on with a left-footed attempt from the edge of the box moments before just failing to control a cross into the box when a goal would have been the likely outcome.
The Argentine again was at the heart of things when his snapshot forced another Courtois save but Ramires was on hand to clear the rebound with Dzeko lurking.
City's hopes of making the most of the ascendancy received a significant blow with just over an hour gone, as Zabaleta received his marching orders after a clip of Costa's heels brought a second yellow card.
That forced Pellegrini into a reshuffle that saw Dzeko make way for Bacary Sagna but the addition of another defender could not prevent Chelsea taking the lead.
The visitors broke incisively from an opposition corner before Costa played Eden Hazard into enough space on the right-hand side to pick out a delightful low cross that Schurrle turned in at the back post.
Costa thumped the post from distance but the hosts responded to rescue an unlikely point in the most incredible of circumstances, Chelsea's record goalscorer Lampard turning home James Milner's smartly volleyed cross.
Lampard predictably refused to celebrate, but even went close to securing a winner as Chelsea's fine early progress was checked for the first time.
