I need some help please..I have a 1990 GT with a 347 stroker that has taken me about a year to get every thing and build. The mods include Roush 200 heads, FMS X cam, Trick flow street heat intake, 30lb injectors, 155 lph fuel pump,75 mm throttle body & spacer and Pro m 75mm mass air.

When I put the engine in and started it for the first time it ran a little rough and would not idle until the engine ran at 2000 rpm for a couple of minutes. I shut the engine off to check fluids and for leaks ect, tried to restart engine and it would not start at all unless the throttle was held wide open. After starting it runs rough and will not idle at all and tries to dies if the rpms fall below 1500.

I have played with the timing with no luck and set the TPS to .97 volts, that seemed to help a little. Please help.

 

Having to go WOT to get it to start is a sign of flooding. During cranking and WOT shuts off the injectors, starting in that condition indicates it was flooded. Check the fuel pressure. When you switch on, the injectors fire for starting, if too much fuel is put in you will have to go to WOT to start. This is a common problem when switching to larger injectors.

 

I will check the fuel pressure. May be the start up at full throttle and flooding is causing the ecu parameters to change fuel delivery and making the engine run rough. thanks

 

It is possible you are getting too much fuel (press too high) with change to larger injectors. Would be best to measure AF ratio if possible, i.e. dyno or wide range monitor.

 

welcome to the forums, sorry i cant answer your question.

 

I checked the fuel pressure and it was 58psi. After setting it to 40 psi the engine runs a lot better and idles, but it is still a little hard to start after it runs for about 5 minutes and shut off. I am making progress.

 

When you go to start it, if it does not catch right away press the gas pedal all the way to the floor while you crank it. It may still be dumping too much gas at startup.