Just had pump replaced a few weeks ago. When I start it up in the morning and drive off, it has a bad hesitation under light acceleration but clears up after highway drive. Turn the key to accessory can barely hear the pump. Could it be a bad pump?? I'm always accustom to hearing the loud whine from the pump so this concerned me. Also could it be the relay not kicking in?? Gonna have a look at that in the morning.

 

What brand pump did you put in?

 

The shop I took it to put a NAPA pump in it. Probably the cheaper one, not sure.

 

Think I had a spectra in that went bad, but it was always loud, the delco I can't even hear. Different pumps seem to have different volumes. The hesitation is probably from something different but you never know. A leak down test would confirm your pump is good.
There's so much stuff that can cause cold hesitation.
Do you have any check engine light on or pending codes with the light not set yet?
Take it down to the place that did the pump and ask them to check for pending codes. They really should do it for you for nothing. Most places still have some concept of costumer service.

 

It did have a code for the vent solenoid so I did that and the purge to be safe. No light now. Disconnected the battery for a few hours to do other stuff. Reconnected and turned key to acc. for a few. Shut it off and restarted it.

Went out this morning to check relay and it sounded a little weak in comparison to what I've heard before but, I could be wrong. Just gonna take it down to my shop and see what they can find.

 

My delco was loud. I replaced it with a airtex also loud. I know some people don't trust anything but delco but I have had zero problems with the airtex, been in there for probably 3 years now. Replace the filter, I think there like $10.

 

It really does sound like the pump is bad. Does it do any better if you knock the tank with a hammer (prime the pump)?

 

Filter was supposed to have been replaced. Haven't tried the hammer thing.

 

When my delco went bad I just used my fist to hit the tank. Worked for 2 years then had to replace the pump.

 

Sounds like a pump issue. Maybe they cracked a fitting or line when installing but who knows.
I would start by checking the fuel pressure at the engine at idle and under load. That will tell you if your pump is doing it's job.