de swap running lean

[silver240sx]

Hello mechanic,

I am at my wits end and need help. I have swaped a KA24E for a KA24DE. My motor has 11.5:1 comp. ratio, pdm-racing's stage II cams, port and polished head, intake, headers, and exhaust. the motor leans out right at 1500 rpm. I have bought an APEX i Super Air Fuel Controller II to fix the fuel. This has not helped. The safcII is telling me that i am not getting any air, which makes sense due to no fuel. I am now leaning towards a vaccumm problem. i cant even drive it to my local friendly nissan dealer for a diagnostic without a tow. even so, with all the mods i would think that they wouldnt even touch it. Could you possibly point me in the right direction on what to fix?? greatly appreciate your help

jamie

[C-Kwik]

If the AFC is registering that the MAF is reading no air, then there is either something wrong in the MAF circuit, or air is not all being routed through the MAF.

[NISTECH]

if you have an oiled air filter try taking it off and run the car[ besure the area infront of the intake tube is clean and free of debris so it doesnt get sucked into the motor] Try it again and see what you get. If it is improved you way over oiled the filter and are restricting the intakes air flow. if ok sheck your intake tube for splits it may be opening a split when the engine torques if thats ok try disconnecting the egr vaccum hose and re test. Try these things and see if it comes up with anything.

[silver240sx]

My problem is those two solenoids on the back of the head are bad. Spent hours today combing over the vaccumm gallery. going to nissan to get new ones. EGR is good. let you know on the progress...

[silver240sx]

OK nissan mechs,

went to nissan today and got a better description of what the 93 FSM says to hook up the vaccumm lines. i eliminated the california emisions stuff from my car. i live in PA so i should be ok. the vac lines are hooked up right.

now, I can rev to 2300 rpm, until my motor leans out. EGR is fine. what else could it possibly be?

since my SAFCII is reading no air, which does point to a MAF, there are four males comming off of the MAF connector, and the wire harness that i have only has three females to attach to it. it is a post 90 wire harness because the harness does hook up to my MAF. would this have a big role in my problem?

would the nissan diagnostic computer read whats wrong with my car with the mods that are done to it?

thanks,jamie

[NISTECH]

on your car there is no diagnostic scan tool. all we have at the dealer to diagnose it is the same thing you look at when you turn the screw on the computer and watch the led's. ours is just a unit that plugs into a connector off the ECM and we have a switch we flip instead of turning the screw and it flashes the red or green led on that box same as it does the ecm. so to answer your question yes all the diagnostics would be functional. If your custome device is telling you no air either the circuit for the airflow meter is going open or you have a gapping hole in your intake somewhere. usuall the whole occurs in the flexable part of the intake tube in one of its grooves. when the engine torques it opens that whole up causeing it to bounce off a specific RPM.

[silver240sx]

found out what the problem was.... MAF. thought i put the good one in, but i put the bad one in. its all good now. thanks for your help.