Harder to start after injector and O2 replacement
 

1996 chevy beretta with the 3.1L v6

I replaced my injectors and O2 sensor today in the quest of better MPG, and after, the first start was rough, but I expected this, what I didnt expect is the start about 4 hours later to struggle. Before this, you would turn the key for under a second and it would fire right up, but now it cranks longer and kind of sputters to life, like it doesnt fire up smoothly, so I drove it, got it warmed up, and it did the same thing warm, took a while to crank, didnt go instantly as it used to, try again for a little longer, sputters to life. But once it is running, it runs fine.

Does anybody have any ideas on what to check? I have no lights indicating anything.

UPDATE:
I did a fuel pressure test, it goes up to around 41 or 42 psi, which according to my manual is normal, but after a few minutes drops down to the low 20s. I starter the engine and it goes down to around 37 which according to the manual is also normal (3-10 psi drop when running). I also checked around the injectors and around the inlet and outlet pipes and there is no fuel around them. So my guess is that some injector is leaking into the engine. Anybody know how to figure this out without taking everything apart? I check the front plugs and they look fine, the back ones are too much of a pain to remove tho lol.

And I have checked the connections on the tester. There is no fuel leaking, nor can I hear any air leaking out of them.

And I used my remote start to start it cold the other day, and it took probably around 4 to 5 seconds before it started and ran.

I would also check the pressure regulator, in the event messing with the fuel rail upset it. May also try resetting the computer to reset fuel trims and learned parameters as well.

Just for giggles, when you start it, hold the throttle open just a little bit when starting it. When it does start right up, let go of the throttle, if it starts acting like its going to die, good chance its the IAC.

Did you exercise the injectors before installing them? If not, it'll probably misfire until they start opening.

I dont think its the issue, but its possible. And how would I reset the computer? Ive left the negative battery cable disconnected if thats what I needed to do. If so, that didnt help

I didnt, but once it starts, it runs just like it always had. Just doesnt like to start

Ok. I replaced the IAC a month ago, so I will test this and see what result I get

If the battery was disconnected it probably lost it's memory. Do an idle relearn. This causes hard starts and stalling until it learns. Do you kn ow how to do the relearn? Many just need to idle in drive with the wheels blocked until the cooling fan cycles.

I do not know how to do the relearn

Did this, it actually started pretty fast this time, immediately shot to 4k rpm and didnt sound happy, but idled down and ran fine