After MAFS change 2002 QX4 Will start after 3 attempts

[mc_wire]

I recently changed the MAFS on my 2002 qx4 but have noticed it will only start after three attemts or after cranking for about 20 secs.What could be responsible for this and how do I sort it out.PSI can only afford after market parts

[elwesso]

have you checked fuel pressure...??

[Q451990]

What prompted the MAF replacement? Did the replacement change anything? What were your symptoms before the replacement?

Heath

[mc_wire]

The replacement was due to the reading form the ecu indicating that the MAFS was out of order repeatedly even after the code was manually cleared. The car wouldn't rev above 2500 and was emitting incomplete combustion fumes. However since changing the cold start problem started. Funny enough at times after parking overnight it would start at the first attempt giving me the impression that it may be a vapour lock problem but cleaning out the fuel lines has not helped. Any ideas as to what might be the cause or do I need to replace the MAFS again. Know any good source?