02 blazer hard start

After replacing the fuel pump on our 02 blazer, it has taken more cranks for it to fire as opposed to before the fuel pump failed when it would start imediately. Well today it left my wife stranded at work. alot of cranking and nothing. I checked for fuel at the rail, and yes the pump was pumping, I checked for spark, and yes the spark was sparking. So as a last resort i got a small amount of gas from the valve at the rail, dumped it into the throttle body, and low and behold it started, go figure. The thing runs smooth with no problems, but had her punch it on the way home to check the reponse from the throttle and it did not respond like it should, ....no passing gear, the tranny would shift down but the engine did not have enough rpms to get it moving. Is there fuel pressure issues, sensor issues or just something im totally over looking? hope someone can help with this one.....thanks

Welcome to AF
Any check engine lights on or flashing?
Fuel filter? Mileage and tune up history?
What kind of fuel pump did you use for a replacement?


Time for a fuel pressure check.
Hard to start cold.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
Later V6 and V8 gm engines should have 60-66 fuel pressure.
Cold start should be 64-65 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel.
Do not leave home without it.
Engine running should be 60-66 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak.
Post back fuel pressure readings.

got pressure gauge, key on, engine not running gage reads about 55, engine running at idle gage reads approx. 53

If your gauge is right the pressure is to low.
Go threw the full test and give us the results.