I have a feeling that this is an easy solution but I can't find the answer for some reason. I have a 91 camaro z28 with the 305 tuned port injection. I just rebuilt the motor and when I went to go fire it up... it just flooded the motor. I can disconnect the injectors and get it to spit and sputter on just carb cleaner but the minute I connect the injectors they start flooding. I have grounded out the A & B terminals on my diagnostic panel and get no codes and have run out of ideas as to how to fix it. Any suggestions?

 

Maybe the ignition module is bad. Got a wire grounding. Check to see if your injectors are pulsing. One wire is hot and the pulse will ge a ground signal. If its got a solid ground then the injectors are staying open from that. If there is a pulse then the injectors them selves may be stuck open. Not sure if the injectors are in series or parallel but if they are in serries then one bad injector can affect the rest.

 

I talked to one of my friends about the problem and he said that it could be the fuel pressure regulator. Would this be of use to replace?

 

When you said it had no codes you ment to say it only had Code 12? Code 12 should be present if the engine is not running. You may also check to make sure your fuel return line is not pinched. You should take a fuel pressure test. If your line is pinched or regulator stopped working you pump will overheat very quickly. It needs fuel flow to keep it cool.

+1 on what Mike said, I have seen ignition problems that causedvery weak spark. That spark would try to fire starting fluid but not fire gas.

Find ainline tester for you plugs, These are not the best but if it will fire this it should fire gas
http://www.harborfreight.com/cpi/cta...temnumber=4445

 

Yes it kept repeating code 12. I did a voltage test on the injector connections and with the ignition on there is a constant voltage. This would cause the injectors to just stay open correct? And the problem would be with the ecm?

 

Alright... I have narrowed it down to either the throttle position sensor or the ecm. The only way I can think of checking is to know the resistance the tps is supposed to have. It has a good difference between open and full... gauge said 1.37-5.5 ohms. Just trying to keep from throwing money at this car...

 

To bad you dont have a scanner. The TPS is easy to check with that. If you have constant voltage at the injector and no code in the computer, well that would be a first for me. Just a heads up some volt meters out there average volts over time. This smooths out the readings, its great for working onwiper motor but not for checking injector pulse.

 

I know what you mean about it possibly giving me an average volt reading but this is with just the ignition on, motor not running, constant volts on the injector. Would it be the ECM?

 

As mike said above you should have power at the injectorall the time the ECU pulses with the ground. If you have ground all the time then yes it could be a computer of a shorted/pinched wire between the ECM and the injector.

 

Ok... I'm completely out of ideas. I checked my tps and it has an acceptable voltage of .47 volts at idle and 4.3 (supposed to be 5 but oh well) on WOT, so I checked the wiring on the injectors and couldn't find any pinched wires. Replaced the ECU and it still isn't starting. About to say just hell with it and put a carb on it..