Zafira A 1.8 16V (Z18XE) running poorly

Here is my 2001 Vauxhall Zafira 1.8 16v Comfort with the Z18XE engine that was running badly, lacking power, struggling under load and uphill and often misfiring on cylinder 4. OPCOM showed a failed MAF (cheap copycat one) and failed front o2 lambda sensor. After replacing and cleaning throttlebody car still runs poorly but better if the working MAF is unplugged.

• #autos_vehicles
• #vauxhall_zafira
• #zafira_a
• #z18xe