Guest jeremy_datsun_1976 Posted March 12, 2004 Share Posted March 12, 2004 I have a stock l28e with turbo injectors,t3 turbo 8psi boost,intercooler,and FMU.I have a war 225 fuel pump and hot wire set up.My question is I can't figure out why I am running lean only when full boost hits around 8 psi.The FMU i thought would help but is does not.My fuel pressure is 40-42 at idel,but when boost hit it just boggs down and goes lean.I have the auto meter a/f gauge hooked up to the boush o2 sensor.I think its in the timeing,But I don't know.Any info would help out . Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted March 12, 2004 Share Posted March 12, 2004 You may be too rich. If you are running higher than stock fuel pressure, 40% more fuel flow with the turbo injectors AND raising fuel pressure under boost, you must be rich rich rich. If you are jumping to the conclusion you are running lean because of your a/f meter, the meter will read lean under extremely rich conditions as there is tons of O2 in the exhaust from misfiring. Check your plugs to verify the mixture, but it sounds like your fuel system need to be rethought. You are running a stock turbo at near stock boost. Install the stock turbo ECU and chuck the "FMU" in the trash, and you should be fine. Quote Link to comment Share on other sites More sharing options...
Guest jeremy_datsun_1976 Posted March 12, 2004 Share Posted March 12, 2004 So I just unplug the 76 ECU and then plug in the turbo ECU.What is the FMU for.I thought this would help,but I guess not.Is there anything else I can do to better tune the fuel with out an aftermarket system.Should I go with a turbo dis,wireing harn,AFM... Thanks Jeremy Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted March 13, 2004 Share Posted March 13, 2004 What I am suggesting is to get the stock turbo EFI running on your engine before you make mods to tune the fuel. Unfortunately the ECU will not plug into the stock harness. You will need to swap the harness, ECU, AFM and distributor from a turbo, in addition to running the turbo injectors. Quote Link to comment Share on other sites More sharing options...
Guest jeremy_datsun_1976 Posted March 13, 2004 Share Posted March 13, 2004 Thanks I guess I should go un hook the FMU and just try running the base fuel pressure.I will hit the JY and see what I can't find.Can the AFM in the stock 76 be adjusted for more fuel.Till then there is nothing I can do to help my problem. Quote Link to comment Share on other sites More sharing options...
Ben Posted March 14, 2004 Share Posted March 14, 2004 That's a lot of idle pressure..... You may also be having a problem where your fuel pressure it too high & the solenoids in the injectors are unable to operate properly. Yuo might want to get the injectors tested for flow & pattern - specifically at the fuel pressure that you are running. Quote Link to comment Share on other sites More sharing options...
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