No Fuel from the fuel pump
Ok to start this let me start from the beginning. I installed the system on a 383 stroker motor I purchased from Blue print engines. It is supposed to put out roughly 420 hp, so I purchased the go efi 600. I wanted the ease of just going out and cranking the car and not having to let it sit for 10 minutes before I could drive it. I installed it with the original fuel command center. Due to fitment issues I was not able to install it in the engine bay. I had to install it under the car close to the rear of the car. I also installed the command center away from all the heat sources I could think of. It seemed to work great for a long time then it developed a fuel cutout problem. I suddenly could not drive it for a undetermined amount of time. One time it would work for hours then other times just a few minutes. I would try to duplicate the problem in the garage on jack stands and it would never do it while I was at home always while I was out driving. I believed at first it was a vapor lock issue. So I installed a secondary electric fuel pump to over come the vapor lock issue. That did not seem to fix my problem. Every time this would happen I could reenergize the pump with my power probe by putting power to the positive side of the pump. Sometimes it would take a few minutes then other times it would regain fuel pressure right away. I could then drive the car again, until the next time. So after many attempts to fix the problem I decided to bite the bullet install a intank fuel pump. At first after the intank fuel pump install the car would not even crank. I tried playing with pwm settings tried max it out, tried setting it 40 and probably everything in between. I tried to use it thru a relay. It is now run straight off of the orange wire off of the throttle body. I was able to after many hours of reading and talking to fitech (who was about useless) I was able to get it running and running great sitting in my garage on jack stands. Then I thought I would try and drive the car on a test drive. Then it happened once again just like when I had the fuel command center it lost all the fuel pressure coming from the fuel pump. Now due to where the fuel pump is I am not as able to just put the power probe on it to repressurize so I had to tow it home (luckily I was only 5 miles away from home). Now that it is home I can check the fuel pump. When I crank the car I get no signal at the fuel pump, no fuel pressure no nothing. I can put the power probe on the positive side and energize the pump that way and I get fuel movement. When I do this for a minute I am able to actually crank the car up for just a few seconds before it dies again due to the lack of fuel. I have tried everything and anything I could think of read about. Now I am asking for help. I have also replaced the pump with a different pump and no change. Any kind of help would be grateful.
To me it definitely seems like the orange wire isn't putting out the voltage when needed. I've never used the orange wire, because my external pump, I was told by the manufacturer, isn't approved for PWM. I just run the pump off a relay triggered by my ignition, and at first returned the excess fuel from the fitech, until the internal regulator went out, and then put in my external pressure regulator, capped off the fitech return, and returned the fuel from my regulator. Now the pressure at the fitech inlet stays right at 58 psi, and the pump runs all the time, keeping it cool. Problem solved.
To isolate the issue, I would try wiring the pump separate from the system. Run a relay switched by the key.
I have seen intermittent fuel pump issues when grounds were not adequate. The grounding on Fitechs can not always make sense, but I have a method that has never failed and has solved dozens of issues.
2ga battery to block, 10ga battery to body, 10ga battery to frame
Ok I have figured out what the problem was.
Before I had someone to help with turning the ignition over while I was checking the voltage. I was not getting any measurable voltage at the fuel pump. So all along I was thinking the same problem as before I was not getting power to the pump. I was able to get someone to help me by cranking the car while I checked the voltage. I was now getting voltage at the pump from the Throttle body, but still no fuel pressure. At this point I knew I had no choice but to remove the fuel pump. It was either bad or something else was wrong but either way I had to pull it. What I found was the feed line had come apart and the pump was just pumping fuel back into the tank. So the fix for now was just something simple, I put a hose clamp on it so now it will not come back apart until the pump fails.
The grounding is always a good place to start. That is what I checked first and I have several ground straps from the battery to the frame, from the trans to the frame the engine to the frame. If this engine ever tried to fall out the ground straps would hold it in.
Thanks for all the help now to get this thing tuned. But that is another topic