I have 98 ford ranger 4.0.
I started up good, from are stable st 800 April.
but when I start driving it. It' hesitate to go i push gas pedal all the way and it goes slow, slow slow, soaks plugs are good, ignition coil has sparks and I check fuel injector 3 and its good.
I change AGR, TPS, Cleaned mass air flow sensor, gas filter is new,
I do not know what else... I do.

 

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Does the CEL(check engine light) work?

It should come on when you turn on the Key, then go off after engine starts

Even if it does work, and is not on when driving, you should get the Codes from computers memory, it's free at auto parts stores.
WRITE THEM DOWN

If you have a Vacuum Gauge you could check if exhaust is partially blocked, rusted out muffler or broken Cat converter.
If not then use a rubber mallet or piece of wood and tap on the exhaust parts and listen for rattling inside.
If exhaust can't get OUT easily then Air/Fuel can not get IN, so very low and slow power