I'm still not opposed to the microcontroller.

I said I'm not a programmer, but I've been playing with the cloud-based TinkerCAD app to see what Arduino code might look like for this project.
Have a look at the resulting attached code (you can just delete the .txt file extension, which is only to allow the file to upload here) in any text editor. Not much to it, is there?

 

It definitely looks like something I could learn. I have knowledge of some other codes and this probably would be easier than those.

That being said I think I have struck a pot of gold. There's a company that is local to me, that happens to just be starting up their electronics/prototyping business. They have actually offered to help for free, and if I was happy with their services I could "donate" to their cause. They made a short proposal for me about how proceeding and are going to price the board and components for me.

Their suggestion was to use the H-bridge that you designed, and control it with a microcontroller, just like you have suggested.

I'm going to keep you all informed on how this is coming along and how things work out!

I want to thank you all that helped out with this project again! I couldn't be as far along with this as I am without your input and expert advice. You have all given me a warm welcome to this forum and peaked my interest in electronics!

 

That being said I think I have struck a pot of gold.

I think you have. Hope it all turns out well. Btw, I edited the post #92 circuit to show MOSFETs better suited to this project, but any readily sourced with a rated Vds ~100V and a low Rds(on) would do.

 

I wanted to share what the cleaning process currently looks like for an eTec injector. You can see when I lift the socket off that the injector is pumping quite a bit of fluid through it.

 

Oops. I thought the +48V 5A supply would be sufficient, but was forgetting its duty cycle would be six times what it presently is for a single injector, assuming all injectors will be pulsed at ~14Hz. Running the sim with six 2.5Ω injectors gives an RMS supply current of ~12A, but only if the injector inductance is at least 2mH (it would be nice to know what it actually is!). Looks like you'll have to trade off supply ampacity for pulse repetition rate.
Btw, I had a further play with Arduino programming and got the code (attached) down to 18 lines.

 

Dear friends,

I came across a problem with one of my etec injectors. i have dismantled the injector and also took out the micro filter basket.
i have placed the injector in my ultrasonic cleaner and drove the injector with pulses, the injector started to inject.

as soon as the injector is installed in the engine, it does not inject any petrol. i have also switched the injector in a different location in the engine and the problem have moved which means the injector is the problem.

i cannot understand why this injector injects properly when it is on the bench submersed in injector cleaner, and in place it does not inject.

it seams that this injector is not able to overcome the pressure in the cylinder.

have some one came across this problem ?

regards

sean

 

Oh Wow!!! This is a very old thread, nearly a year.

 

i cannot understand why this injector injects properly ...

it seams that this injector is not able to overcome the pressure in the cylinder

I think you've nailed it. No idea why but it could be electrical or mechanical. Not yet being fully clean is one possible mechanical cause that there is hope of fixing. If it's a bad seal or some other mechanical issue, or an electrical issue like a weak coil (due to a winding breakdown, for instance), I have a hunch there's little that can be done.

 

If your certian it is 100% clean, and its not pumping, it is shot. Pretty common on these. Also don't swap them cylinder to cylinder. They MUST be put back in the same cylinders they came out of.

 

When you test it on the bench, are you using the same fuel pressure that it's pressurized with in the motor? Maybe that's the problem. Have you compared the impedance of the coil with the spec? Maybe the coil is shorted causing a weaker than normal action.

 

Hi guys, I need some help designing a system to pulse eTec fuel injectors. I am using this system to pulse the injectors outside of the motor for cleaning purposes.

I have a machine that does this already in a more complex form so I think designing this should be relatively simple. The unit I have normally runs 12v style injectors, but with the "add on box" can run a single 55v eTec injector.

I'm hoping to make this a standalone unit so I can keep using my other machine while the eTec injectors are sitting there cleaning.

The thread below is from a few years back where someone tried the same thing. It is unclear if he ever got it working.

https://forum.allaboutcircuits.com/...-the-polarity-of-a-55-volt-dc-circuit.119221/
Good morning InjectorService
I am curious as to the progress of the multiple e-tec injector pulse system? I am having the same dilemma. Any help would be apricated.

 

This seems like it should indeed be a reasonable project. But there are questions prior to designing a pulser, which I presume that to clean an injector requires more than just operating it to open and flow the cleaning solution.
so the first questions are how much current must be delivered, and the second question is how long can those pulses be?? And is there a specific duty cycle that must never be exceeded? Then there is a question about the pulse rate, which I presume can be similar to the engine firing rate, probably not exceeding 200 Hz.
The electrical injectors that I once designed a tester for were about one ohm resistance and fairly inductive, so handling the inductive spike may require additional effort. I see both 12 volts and 55 volts mentioned so the requirement may not be simple.

So please let us know the answers to the questions.