PDA

View Full Version : Fuel Inject Pulese per Second?



acidice333
10-17-2006, 10:36 PM
On a warm 5sfe engine, what kind of pulse reading should I be seeing on either of the two injector wires going to the ECU?

Dr.Auto
10-18-2006, 03:16 AM
?why? :squint:

acidice333
10-18-2006, 05:32 AM
For me to know and you to find out lol.
I would actually find out myself but I dont have the proper equipment.
Also would be nice to know the RPM pulses too (:

Dr.Auto
10-19-2006, 05:27 AM
well........ I find this odd.

The question: "fuel inject pulses per second"..........?
that is the wrong type of question to ask in order to get a answer you can use. Because fuel injectors aren't pulsed relative to time in seconds. But rather in millaseconds. As a generic point they can range from maybe 1Ms to sometimes 3Ms...(just an illistration)........ much of this depends on injector impedance weather they are wired in parrallel (for group firing) or wired seperately (typically for MPI). The flow rate of the injectors and impedance has a huge factor with determining injector pulse width, duty cycle, and operating voltage......not mentioning other possibilities such as resistor packs with low impedance injectors and fuel pressure, then drifting into the VE of the engine and displacment, and RPM's................. I think you neeed to do some more reading perhaps.....

http://auto.howstuffworks.com/fuel-injection5.htm
http://www.robietherobot.com/Storm/fuelinjectorguide.htm
http://www.rceng.com/technical.htm
http://www.picotech.com/auto/tutorials/fuel-injection.html

Given I know nothing about the intended use of this information leaves me wondering how to answer this question. All I will say.....is please either ask a more dirrect question/or ask the question correctly(like "what is the typical duty cycle on injectors on a 5S-FE")......or do your own research and answer your own question. Because to need to know this information I would hope means that you know what to do with it.......... but then.........you should be able to answer your own question if you already know what your going to do with it. So why are you asking?..........and since you are asking......do you really need to know?

I mean, to compensate for any mods (including boost) you wouldn't even really need to know this because you would be more interseted in duty cycle than anything else.......then after that injectors with a higher flow rating, and increased fuel flow and/or pressure.

So................................... :squint:

my origional qestion once again............?why? :squint:

RPM pulses .......... (wrong question again, should be "What kind of a distributor signal is there?")..........but it is a more resonable question than the previous.

The answer........there are two signals from the distributor sent to the ECU. One is a 4 tooth "G" pickup, and the other is a 24 tooth "Ne" pickup. The distributor is driven off the camshaft and camshaft revolution (RPM) is half of the crankshaft.

Hope this helps........ :ugh: but I have a feeling.........not too much. I suspect you are messing around with some kind of a standalone fuel managmet? that's the only thing I can come up with to justify these type of questions......or maybe piggy-back modules?