[Cda55]

I have been working on a 94 3.4 for my son. It has a hard time starting. Cranks just fine but stumbles very bad until you can get it above about 1200 rpm. Once in a while it acts like it loads up and won't crank. But the battery is still 12 vts(new also) After that it runs like a top. But, if you shut it off it's the same thing all over again. After you get it over 1200 it will idle at 900 or so all day long. Why the hard start? I have cleaned the egr, cleaned the idle control valve and port, have a new map sensor coming in the morning, all general stuff is done(plugs wires filter). I am stumped here guys. Any help would be great!

 

[Everett#2390]

It reads like it is cold fueling, as in choke is closed, richer mixture, but not fast idling as needed.

You can check the cold fueling by removing a spark plug and seeing if the electrodes are wet with fuel - good thing, means there is no air - IAC should open up - retracts the pintle out from the hole - to idle up.

Pull fuel regulator hose and see if hose is damp inside. It should not be damp, dry is good.

 

[SPARKY69]

Welcome to team camaro
and adding to the above, check your fuel pressure also?
Im leaning towards fuel reg or injectors leaking down?

 

[Cda55]

Thanks for the info. OK, I have since changed the IAC, TPS and starter. The starter is fine now. It no longer drags. But it still has the hard start problem. Runs great once it starts. The secondary air pump is smoked. Can this add to the problem? The map sensor has also been changed. Could it be a knock sensor? Cam sensor? Crank? I have never worked on a 3.4 so I am a little lost.