So I finally have found time to work on the firebird recently. I did a 3.4 swap on it not too long ago and got it timed and running. Well today I went to start the car and it wont stay running. It starts and dies instantly. I can press the gas pedal and it will run but sputter badly. I checked fuel pressure and I am definitely getting fuel at the rail. Timing was also checked. It almost seems like it is not getting spark until I floor the pedal. Any ideas would be helpful.

 

What is the fuel pressure readings? 'Getting fuel at the rail' doesn't tell me much.
Check for spark while trying to start it.
Check your throttle postion sensor, you'll need a volt meter & service manual.
Any codes?
Did you use 2.8L injectors for the swap?

 

Eh, quite wrong. Das boot, gives it more air and fuel, doesn't do anything to the spark whatsoever, not directly anyway. So, probably a fuel issue, try starting it on starter fluid, see if it fires up without pedal. Question though, if you rev it good, does it still sputter, or just at idle or close to idle RPMs, also, once you fire it up with the aid of the pedal, does it stay running?
If you messed up a vacuum line that could also do it, more than once I've bumped a vac line on my corsica(they pop out so easily..) 2 in particular that pop out all the time, anyway, it runs like poo when it happens and I don't even have to guess why its running shitty, just shut it down and go right to the vac lines.
Lack of, or not enough of, fuel will also cause said issue.

 

Fuel pressure was 35PSI at the rail. Im pretty sure its suppose to get roughly 36PSI so Im in the correct ballpark. With the aid of the gas pedal I can keep rev it up. However it will not idle and will die as soon as I let off the gas pedal. It has to be at WOT for it to run. Even at half throttle it doesnt run. Also injectors are the 3.4 injectors not the 2.8. Engine has no codes. I will check for spark later when it stops raining.

 

I think the pressure should be 43. ? Did you check the injectors before installing them?

 

The injectors were tested and worked fine before reinstallation. I had then cleaned aswell. he fuel pressure is suppose to be 36PSI according to my shop manual.

 

Don't know what shop manual you're using, but both of mine (87 and 92 GM) say no less than 37 PSI at the fuel rail (37-47 PSI), holding for 20 minutes without losing 1 PSI fuel pressure.

Need to check for codes before you do anything else... Almost sounds like a MAF issue to me, or something similar, but nobody can tell without and DTC's.

 

Ah you guys are right I checked the manual wrong. Anyhow the fuel pressure should be around 41-47 according to my manual. Also I tried swapping out MAFs. I have 4 OEM GM MAFs and swapped them all out and cleaned them. It still wont run. Also the engine isnt giving me codes. I only get code 12 which is normal. Funny thing is it ran perfectly fine about a month ago. Now I cant keep it running. Could the spark be too low? I still havent had a chance to check the ignition system but will get to it this weekend. I also plan on checking the fuel pressure again as I have a feeling I read it wrong. Im almost positive the fuel system is fine.

 

Should start w/ 30psi, pump might be weak or filter is blocked.