sweet93

I've tried for over a month to figure out this problem. This is the best I can come up. After rebuilding my motor and installing my 1680 secondaries, sx regulator, and rp comp fuel pump the car would fall flat on it's face as soon as it hit 2lbs of boost. I thought it was running too rich before we put a datalogit on it and found it was going extremely lean. A buddy of mine adjusted the maps to take care of the lean mixture and now it only goes extremely lean about the time the secondaries are to kick in. I thought my 1680s were bad so I changed back to my 850 setup and still have the same problem. My fuel pressure at idle is 43 and goes up to about 55 while boosting. As the car leans out the fuel pressure does not change. I've checked the resistance on each of my secondary injector wires and they all have the same resistance so there shouldn't be a broken wire or anything. I'm at a loss. Where do I go from here? Is there any way to test if the secondaries are coming online? What tells the secondaries to come online at 3700 RPMs? Any help would be great! Thanks

Mr3plus1

iTrader: (5)

Maybe you're not getting enough fuel up there. Those are some huge injectors. What kind of pump are you running? You might want to look into running a dual pump setup.

sweet93

I've upgrade my fuel pump to the Rotary Performance Competition fuel pump. I thought it might be the lack of fuel also but I have steady fuel pressure and it leans out the same with my 850cc stock injectors, right around 3700 RPMs. I know there's plenty of fuel for them. It acts like the secondaries are not come online. Any other ideas? Thanks

dgeesaman

iTrader: (7)

Take the injectors out and have them cleaned and tested by a proper injector shop. No way I'd risk an engine doing that.

Dave

sweet93

Thanks for the suggestion but it's already been done. The 1680 were new from kgparts.com and the 550's and 850's were cleaned and tested my RC Engineering. I thought maybe the 1680's were bad so I put the 850's back in and it didn't do anything different. Same problem. Thanks!

d1rx7

bit more over here lol

dgeesaman

iTrader: (7)

What is your fuel pressure doing when you go lean?

Dave

RX7Wishing

he said "My fuel pressure at idle is 43 and goes up to about 55 while boosting. As the car leans out the fuel pressure does not change"

RX7Wishing

are you're 1600's even kicking on as they should be?

sweet93

I don't know if the secondaries are coming on or not. Is there any safe way of testing them? What causes the secondaries to come on at 3700 rpms anyway?

DaleClark

iTrader: (55)

I'm assuming you're running a PowerFC. If you're running large injectors, they're going to be low impedance. Do you have resistors for the larger injectors? Without resistors, you'll have problems, may even burn up the injector drivers in the PFC.

Dale

dgeesaman

iTrader: (7)

You're allowed to smack me when i miss basic stuff like that.

sweet93

Yeah, I'm running the PowerFC. I installed the larger injectors with 10 ohm resistors to be able to run them. After I gave up with them, I rewired the old plugs and stock injectors back in. Right now the only thing left not stock in the fuel system is sx fuel pressure regulator, rp comp fuel pump, and powerfc.

Jaime

LUPE

Search the work "Overlap" in the Power FC forum.

That should fix your problem

sweet93

Thanks but I'm not finding anything. What exactly am I looking for. When I search for "overlap" in the PFC forum it pulls up 10 pages of junk. Just searching for a title in PFC forum, I don't find one either.

LUPE

Change your overlap to 7-7-4. You'll need to do this with the datalogit.

sweet93

Thanks! Right now I have the stock 550 and 850 injectors installed. Will that effect anything? I'll try this as soon as possible but I'm down with the flu so I'll be a few days. Thanks again.