I have a 2002 Pontiac Aztekit wouldn't start after I stopped at the station been told it was the fuel pump but where did start at all if the fuel pump was actually the problem

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Question moved to model category.

When you replaced the fuel pump, did you disconnect the battery? If you did, did you reset the security system and engine immobilizer?

first most GM OEM systems will need to recognize the key first and foremost ,to do that you will need to roll window down on driver door,turn the key to the run position and with engine NOT running leave the key on for 10 minutes exactly ..then turn ignition off then try to start engine. if original system is working engine should start normally

When you replaced the pump did you check the fuel pressure with a gauge ?

what mileage,spark plugs,fuel filter[,coils module,this #1]

check if there is spark at the spark plug cables, it's either the coil or the camshaft sensor.

Fuel filter,air filter,could be fuel pump,

probably the crank sensor, above the starter on the firewall side-no crank signal, no fuel pump activation.

Did you replace th fuel filter ??

I would agree with the possible weak fuel pump. The other possibility is the fuel filter. Has that been changed recently?

check fuel pump relay under hood in fuse box