Fuel running out up top

[pur97tsifwd]

My fuel trims low is 99.6 mid is 97.6 and my high is 89.0 i dont get any knock till around 5 grand then i get around 20 counts of knock and my 02 voltage falls down and i go lean.. I have 650cc injectors 190lph pump and im on 12psi. I dont have a fuel pressure regulator or pump rewire. I am thinking i need to rewire it that is why i am going lean. Does this seem right has anyone had the same problem. I have tried richening up the safc on high from 5 to 7grand but still get knock.

 

[hediki12]

ok umm what are you using to log and tune? i looked @ your profile n u have no e--management(im assuming)... you cant just throw bigger injectors in..... umm fuel trims seem fine except for high.but a 89% would mean your running rich (ecu is trying to compensate for excessive fuel). dont follow you o2 sensor get a wide band asap before you do any more tuning and try to get a actual log up to see if there phantom or real knock 3 counts of knock should pull timing by 1 deg so 20 counts shoul pull 6-7 degs of timing..

 

[pur97tsifwd]

Im using mmcd1.8g and a safc and i would post a log but i am using a m125 with vista and it wont work.

 

[DJ23GSX]

I had a similiar problem. Knocking from 5-7k no matter how much fuel I added. It ended up being my year old walbro was dying. Is your fuel pump whining loud?

It could be a few things though. Here's a list of things I checked or replaced when trying to fix the issue.

New O ring in between the fuel pump and sending unit. It didn't work so I cut the bell off the sending unit and connected the pump to it with rubber fuel line and hose clamps to ensure it wasn't leaking under pressure.

had my aeromotive afpr rebuilt by aeromotive

Swapped out injectors

new o2 and knock sensors

I must of retorqued the knock sensor a dozen times to ensure it wasn't phantom knock

lowered base timing


Do you have any clue what your base timing is set at? Whats your timing look like just before you start knocking? Too much timing will cause knock as well. I had that issue too. Are you running the 650's with just an safc to compensate? That could be an issue as well. What are your hi safc settings from 3-7k?