Hey guys, let me give you a bit of background before I explain my problem. I have a single turbo 93 rx7 that was built by rotaryrebuildstore.com and recently tuned by speed 1. Just recently started driving the car a bit more and decided to change my walbro out for a denso tt supra pump.
Recently decided to go ahead and put the pump in. When I first started it it was fine, however, the pump would always need to be "primed" everytime i started the car to get fuel in the line after long periods of sitting.
I drove it for 2 days to work as I had no other transportation. On my way back from work on the second day i went to the gas station and got gas everything was fine. I was driving down the road and got on it a bit and noticed that it hesitated a tiny bit like when it was untuned and dumping fuel. I looked at my afr gauge and noticed it kept dropping way down. I instantly slowed down and started driving normal and the hesitation got worse and noticed my afr eventually just flatlined to 10. I barely got it down the road before it was just flooded out and couldnt start so i had to push/roll it the rest of the way. As soon as i got home I changed the pump back to my walbro and yanked my plugs. They were wet and totally fouled. Put an extra set in and tried starting it. It will not stay running unless you keep feathering the throttle. The fuel pressure is fine as I was checking that while my buddy was in the car tryin to keep it running. However my concern is that he said my injector duty cycle shot way up when he was giving it gas. close to 70 percent, and its still settling at 10-10.5 depending on how much gas you give it to keep it running. I have no idea what to think or where to start guys. Any ideas or a point in the right direction would be great as I dont have a datalogit so I can upload any info from the ecu.
Im running a garret t04s, tial 44mm wastegate, PowerFC, 3bar map sensor coolingmist stage 1 watermeth, rx7store fuel kit/ 1680s w/kgparts fuel rail and aermotive reg, motor rebuilt by rotaryrebuildstore.com. Motor just tuned 2 weeks ago by Dave @ Speed 1.

 

There are too many things to check out.

BUT, since the problem started with you changing the fuel pump, start there.
They never need priming after the first prime unles you messed up the installation.
After all, the pump is in the tank and under the fuel level.

Then you set the base fuel pressure at 0 psi by priming and adjusting the FPR to get it.

Most likely this is all over you head, so take the car back to your tuner.

 

Never did that. Will when I get home. So its basically pushing fuel past my injectors and not reading tight on the fp gage?

 

My tuner is 4 hrs away. So I'm gonna hafta try to figure it out myself before I trailer it down.

 

I thought about what you said and that makes no sense. i have an adjustable reg. fuel pressure is set with vaccum off and the car running. how am i going to do that when my car wont stay running. on top of that. when i swapped from the factory to the walbro in the beginning I didnt do what you said and it was perfectly fine... As soon as I got home I changed back to the walbro.. And as far as botched installation, its kinda hard to mess up.. it either works or it doesnt..

no one has any ideas?

 

jumper the F/P and GND terminal in the diagnostic box to pressurize the fuel system with the engine off.

 

alright.. and when i do this i should set the reg back to 0 then try to start it?

 

Im not seeing where this has to do with my issue?

 

So I'm screwed? no one has any ideas???

 

fuel system pressurizes... back to where i started.. any more ideas

 

It has nothing to do with the pump or the FPR, it's a signal from the ECU to the injector telling how much fuel needs to be squirted in...

what is your water neck temp sensor reading ...-50 degrees as the coolant temperature - some thing like that would make ecu dump fuel

check for any broken wires