hey guys im having a problem with my secondaries and was going to check injector pulse, should i have injector pulse on the secondaries when cranking?

 

I thought the secondaries were off until boost.

 

No only the primary injectors should give you a pulse,when cranking, the secondaries will only show up after they are brought online depending on what you have them set to if you have a different computer they should come on at approx 3300 to 3800, It all depends on what you have for injectors on your primarys and how they are pulsed

 

so what is the best way to check to make sure im getting pulse to these? the problem im having is that when i get to about 4k rpm it bogs and runs lean, like my secondaries arent working and im leaning towards injector pulse because i recently had my injectors cleaned and flow tested.

 

anyone?

 

bump

 

to test your injectors I use small lights simmilar to the type used on 1st and second gen dash lights,wire them into the secondary injector ground wires inside the car near the computer ( these turn on your second injectors) wire one light for each injector then drive the car fast enough to engage the secondarys (best done at night,easier to see)if the injectors are turning on, the lights will pulse or flash on and off ,if not you might have either a broken wire, or loose connection,or a damaged computer, another thing you might be suffering from is a week fuel pump or plugged pre filter screen on the fuel pump intake,just remove the pump from the gas tank and check the screen they are cheep and easy to change, I would also run a fuel pump pressure test on the fuel line and test it ,under wide open throttle ,if the pressure drops under wide open throttle,you have a poor fuel pump ,or a pump that is not able to supply your car with enough fuel, if you can run a check on your computer,and see if it was set up properly,I guessing that you are using a aftermarket computer , which can be programed to bring the secondary injectors on line when you need the fuel,the only other thing that might be is the size of the Injectors you have installed,if they are too small they will not be able to provide enough fuel to stop the lean condition you are getting..good luck FP

 

yes im running a pfc and 4 850s, is there a setting in the pfc that would make my secondaries not function?

 

I had this same problem, it turned out being my clip was not locking the connector in place and it would work loose. It was the front one only and it totally F*ed the power. I would test your wires and connectors to make sure you don't have an open circuit.

Good luck!

 

you have datalogit? If so, I am sure you can log the duty cycles on all injectors. Do that and see if you're injectors are doing what they are supposed to.

-AzEKnightz

 

about those 850's and that big ole t78 i would imagine its capable of 500 hp ,but your injectors are only good for about 340 barely 'I would replace the secondary injectors with a nice set of 1600 cc injectors and recalibrate your computer to accept them, they will take care of any lean burn you are having

 

i have access to a datalogit, ill try getting it and do some logging. i know by injectors are to small but i would atleast try to get them working, i think i need to get that problem figured out before i get different injectors. i was asking about the pfc and if there is a setting that would tell the secondaries to not function because the problem i am having only started when i put this map for 4 850s i got. i put it on the dyno last summer with a different map and had no bogging issues but was still lean, so i got a map for 4 850s and loaded it and have had problems ever since.

 

It may not be that the pfc is turning off your injectors rather it may be stopping them from turning on long enough(pulse width. or duration of fuel injected , per intake event)that would make them come on either late or shut off to early,you can either go back to your first map, and start from scratch,or reduce your turbo boost and the need for the lean burn at the top end due to not enough fuel,or you could try to install a variable, rising rate fuel pressure regulator to allow the fuel pump to pump at a higher fuel pressure according to boost pressure requirements then you would not have to reduce the horse power and boost (with in limits)you are using, the best advice I could give you is call Peter Farrell Supercars and get the info you need then try using a specific map,with their recomdations