OK,

I hooked up a pig-tail to this injector. Then I got a 9V battery and tapped the pig-tail numerous times.

I never hear the injector click - and I'm assuming that it should.

The pig-tail does spark though - as if there is a short - which seems odd.

So, what is that telling me?

BTW - PO has said that all the injectors were cleaned and tested and all tested and sprayed well. They were however sitting in a baggy for three months. I can't imagine that they just went south????

All four injectors and the cold start valve all behave the same way.

Thanks,

Len

Click to view attachment

These operate at 3 volts. I use a DC model train transformer. Use a multimeter to set it at 3 volts and you're ready to go. Ray

They do operate at 3V but, in the past I have tested injectors with a 9V battery and if they click I consider them good, electrically.

OK,

So there is NO click under power.

They ohm out at about 2.5 ohm (which I think is OK).

The pintles do not budge.

I can only assume that they may be OK (ohm test), but stuck - pintle not able to move.

I'll soak them in PB blaster - and see it they'll loosen up?

If the pintle won't budge after the soaking (i've used diesel, injector cleaner, etc.) try ultrasonic, then if still stuck they're junk.
That said I've had good luck soaking them.

Dude, you have three threads going for the same problem.
What are you soaking them in?
Are you submersing them all the way to ensure the cleaner gets into both sides....in the tip is useless, it's closed.
You need to dunk them overnight.
Wiggle them around to get the air out and the cleaner in.

Rich

try some different test leads and a different battery. Im guessing there is a reason that plug isnt on the car anymore.

Got them submersed in Textron cleaner... will test again tomorrow.

Soaked overnight - no change.

I spoke with the PO again about the injectors.

They were pulled out of a car that sat for years and sent for testing / cleaning. The shop did say they needed some work, but they got them cleaned up and spraying well.

That was about six months ago. Since that time they sat in a plastic baggie until I put them into the car.

I didn't think I needed to test them, as I knew they were supposed to be fine.

Anyway, they don't click, the pintle doesn't move, I can't move anything through them at all under pressure - in or out. (not sure if that can even be done anyway?)

I can keep soaking them, but they have been soaking for over 12 hours now.

It is sort of hard for me to believe they were OK and now are not OK, even for sitting for a while. I would think that the Textron bathing would have freed at least ONE of them up.

Very frustrating.

I have seen this before. The injectors must be installed and put into service right away or they can freeze-up again. No worries, just get them recleaned, they should work again. If you have paperwork for the shop that did them before, they may be willing to redo them at no charge.

Is the pigtail you made any good? Just a thought...

Thanks, but I'm sure they are fine. When I tap the two ends to power, I get spark, so I'm fairly sure the wires are OK - otherwise, I wouldn't get anything.

I've also tried alligator clips - same result.

Haven't tried just plain old wire but something tells me the results will be the same.

OK,

Another question that I don't have an answer for:

Let's assume that whatever the "electrical component" inside this thing is toast - as in these injectors will never click again.

That said, shouldn't the pintle (the small needle that comes out the bottom) move by pushing it with something blunt and soft?

The electrical component inside is a solenoid. It probably pulls the pintle up, inside the body to allow fuel to flow based on the diagram I have seen. That said, the movement would be miniscule.

So there would be no way to feel or see this movement if it is that little.

I read that the ohm readings (to test the solenoid) should under 3 omhs... I get like 2.5 ohms for all four injectors.

So can I assume then that the solenoids are OK and I'm just dealing with a really stubborn set of stuck injectors?

Still makes me wonder when they were cleaned six months ago what was used to store them. I'm beginning to think it may have been JB weld or something.

Makes no sense.

You can hear a click when activated. Seems to me it can be felt too, when the pintle moveds

Jeff, I'm not hearing or feeling anything.

I put two 1.5 volt batteries in line to get to 3 volts. When I apply this power to any injector, the only noise I hear is the spark created when I tap the power source. There is NO clicking in the injector at all.

I've seen videos of injectors being tested, so I'm sure that if I heard one click, I'd realize what it was. Just not happening.

So are the OHM readings meaningful or am I just wasting my time trying to figure the electrical side out?

I can deal with them being "stuck" so to speak, but if they are no good electrically, that's another game.

Thanks,

Len

Seems to me I have specs somewhere that show them to have 2.7 ohms, so yours are good electrically. They are just stuck. Send 'em in to get them unstuck.

Consider reading this thread, he went thru the same exact problem you are having now. stuck fuel injectors

did you soak them?
If so, what did you soak them in and for how long?

Did you soak just the tips or did you submerse them completely?

Rich

My 993 injectors were all frozen when I got the engine. 9v battery after a good soakin' in gasoline overnight worked only after I tapped the bases with vigor on a piece of wood while they were electrified. Then all worked fine. 9 volts is too much though so don't do it long. The longest I energized them was about five seconds at a time.

Good luck!

Been soaking in Techtron - fully submersed since yesterday about 5PM - so call it 20 hours. I'm in no major rush, I can let the soak the rest of the week for that matter.

I made sure to shake them to get bubbles out.

Take any of them out, dry them off, hit them with a quick 9V current and nothing.

I've tried banging the sides and sort of trying to shock them up / down sideways, but for fear of breaking something I'm not being too forceful. Like I'll use the butt end of a screwdriver to tap them with... then hook em back up - touch them up to 9V for a spirt - and nothing.

Maybe Jeff can chime in about why when I touch them up to power - by attaching one wire to positive, then taking the other wire and slapping the negative side, all I get is sparks from the slapping - but for sure not clicking the silly solenoid.

OK, so that has to be hard to do, how do you apply power and tap them with vigor at the same time?

And how much vigor are you talking about?

They are obviously stuck closed. Send them in for pro cleaning.

You should try installing a grease zerk on each injector and pump them up with grease till they free up! Kidding!!! You should send them off to the injector specialists like Witch Hunters.

German Car + German Owner = Stubborn Situation

The part I'm hung up on is they were just cleaned six months ago - so I would think that soaking them in decent cleaner would be an easy fix.

I most likely will end up sending them in for professional cleaning. I already contacted Rich at Cruzin Performance - he's out all week, so it don't matter if I ship them today or Friday...

Until then, can't hurt to keep trying.

I had a very similar problem with two of my injectors. Car had been sitting idle for about 8 years before I got it. I removed the mesh screen in the inlet and soaked in Techtron for probably 4-5 days. Also probably an hour of so in an ultrasonic bath of Techtron. Used a 9v battery similar to you and they finally started working (and still do). I also use Techton in my gas tank periodically and have had no problems since.

Good luck,

Keith

All a professional will do is soak them.
If they won't budge, he will make you buy new ones.


The unit is an electro magnet....so when the inner piston shaped magnet stays in the same position and does not move, it create a huge draw on the circuit, then you get a spark
Once it moves, the spark will stop or get a whole lot smaller.


While you wait, you could go to RadioShack and get two small spade bits to make a pig tail that will stay on while you smack them.
Get the transistor battery plug end also.

I use an AA battery cause I really don't keep transisitor batteries around anymore and I believe it may be too much voltage for the injector.

Rich

I'm not sure Techtron will work.
I used an ultrasonic bath with degreaser for about 10 minutes. It worked most of the time. I think the ultrasonic bath is the key.

Mesh screen?? I don't see a screen anywhere. The only part that I can see that comes off the injector is the plastic tip. The top side - where the fuel hose connects, just looks like a black hole to me - there's no screen in there and it is only about 1/4 inch opening.

If there is a screen, I don't see it.

Inside the fuel inlet, there is a micro-screen to filter the fuel. It is replaced when the injector is "rebuilt".

Let's end this...

I'm beyond guessing what the deal is and I'm moving forward.

I went to a BMW club meeting last night (I'm one of the directors) and one of the Motor Sports members told me about a local shop that does turbo's and FI systems, so I took my injectors to them this morning.

There were no screens in any of them. They all tested OK for resistance, so they're fairly sure they can get them working for me. I'll know later this afternoon.

They will put new screens in and I'll get a report. When I get them back they are sealed in a vacuum pouch and lubed with wd-40 for storage.

Thanks for all the insights and help!

FWIW I had two experiences or ideas. First, you don't want to leave them hooked up for more than a moment - they don't normally see a sustained 9v so I would worry about overheating a wire before you ever new it.

Second, backflushing with compressed air and cleaner worked well for me - while activating the injector. The junk tends to get pushed in from the inlet and has an easier time going back out that way. I never did hear a click, but you can certainly feel it. Maybe my ears aren't as sensitive as they oughta be. No screens on a car this old can't be good, so the shop should at least get you that.

Yeah, the shop just called.

Two ultrasonic baths and they can't get them to pulse either. They are going to bathe them overnight and see what the deal is tomorrow.

Assuming they were cleaned six months ago (really), I think just keeping them in a baggie with other parts and without screens, well you fill in the blanks.

From what I've learned (thanks to all your replies and insights), it is SOP for any cleaning service to put new screens on after cleaning. No clue why the screens were missing from these, or why they were just tossed in a baggie with other parts.

My first FI car... and so far it has been a real education. I think once I get over this and get that FI running, I'm gonna never go back to carbs. Just wish I had a better hand dealt to me (as far as the FI system goes). Oh well, its all fixable.

Great way of looking at it Len. Lemonade from lemons. You will like the D-Jet once it all comes together. I rarely have to fiddle with mine, and its very reliable.

Have you licked that 9v battery lately? You sure it's good?

my thoughts exactly.

We have similar "valves" in my business.
Our systems usually "Hit" the valve with full bus voltage (in the case of our cars that is ~13 Volts running), to open it.
Then the voltage drops to just a few volts to hold it open for extended periods.

I would not be surprised if these systems hit the injector with 12V at the start of the "fire" then backed it down to 3V for the duration.

I cannot see any captured waveforms of our injector pulses with an oscope online to be sure.

The rated coil resistance of these is 2-3 Ohms so "hitting" them with 12V from a reputable "source" :-) for a "touch test" should not hurt them. ("touch" meaning long enough to see the spark and no more)

I would try a nice stiff12V battery and a quick "touch" to see if you can free them after a good soaking.

Stu

Oh... I got some captures.
Ping me if I forget to upload them tonight.

For those following the drama.

The shop couldn't get them to fire, so they bathed them overnight and called me this morning.

Bottom line - they can't get them to work either. They still pass resistance testing, but they are most likely rusted shut.

Odd for injectors cleaned just six months ago.

SO - anyone have a WORKING set of 2.0 injectors? I'm in the hunt.

Len

I just went through this on a friends car that uses the same injectors. We cleaned them about 6 weeks ago in my ultrasonic cleaner and bagged them. Last week we went to fire up the motor and only had 2 working inectors. So I pulled the offending injectors and bench tested them just like you had done. No click, but passed electrical test. They were just stuck.

I simply banged them against the corner of my vise on the work bench a couple times and that was all it took. They began to click and the car was soon running on all 4 cylinders again. The moral of the story is this: If they don't work now, what's it gonna hurt them to get bashed a bit on the vise and see if that un-freezes them?? If they break,. . . well,. . . they're already broken so you have nothing to loose.

Len, I just sent in 8 - 2.0 injectors for cleaning and flow testing, 4 are going in my car, the other 4, assuming they all work well, I was planning on putting up for sale.
Not sure what they're worth. But they're yours if you want them, make me a reasonable offer. Should get them back next week sometime.

Jeff

Let me know when they come back - with luck you'll get 8 good working ones back.

Thanks,

Len

PS - The PO as I said claimed they were cleaned just prior to me getting the car. Turns out there were two sets of injectors - the other set (I think) may be the good set and that set is MIA - but there are three people trying to find them: me, the PO, and the shop that did the cleaning. So maybe, just maybe they may turn up. Wouldn't that be sweet?

That would be sweet if you find them, good luck.
I'll let you know when I get mine back, all tested good with battery.

Jeff

Ya know, I have said for years that the best tool I've ever purchased was my 3 pound sledge hammer. Would you know that soaking them in blaster overnight, then whacking the crap out of them on the sides, freed all four up. Now they click... of course I feel like I'm way ahead of the game, but who knows if I damaged them in the process?

Anyway, I also found out that if you hold them upside down (fuel supply nipple pointing down) and gently tap them on something solid - you dislodge any fluid and associated gunk and it comes out. When I did this to each injector, the stuff coming out was discolored (rusty looking) stuff. If I clicked an injector, then removed as much gunk by tapping upside down, the click would get louder and louder. So I did this until I couldn't get any more gunk out.

I'm taking them into the shop again for cleaning, screens - and hope they are good enough to run with.. at least for now.

Stu, you are really missing out then. Check this out.
http://members.rennlist.com/pbanders/DJetParts.htm

Diagrams and oscilloscope traces galore.

Mr. Anders has done a tremendous service in helping us understand these things.

Finally got to upload this.

This is the power at the L-Jet injector terminals. The channel is obviously reversed. You can see that the injector is triggered at 12v and the spikes are created by the injector inductance.

The injection interval is 13ms and the L-Jet injects 2 times per stroke (every revolution) so this picture is at 4615 RPM.
Enjoy.

Click to view attachment

Cool, but where is the voltage?

The voltage is the vertical axis. Each major line is 5V. 0V is where the 1-> points on the left side of the picture, making the bottom of the graph -13.5V (again, the probe +/-were inverted). This means that the injector squirts when the graph is in the lower section.

Valy,

Thanks for the scope capture.
It sure looks like a full 12-13 volts at the injector.
I couldnt figure out the rate...

Every 13ms (period) is ~77 Hz yet the description was high revs....
I dont understand the injector timing for these.

You can even see the injector valve (pintle?) response time at ~2ms.
It would be cool to have a current trace to go along with that voltage trace.

However based on that Voltage trace, the injectors use 12V when running.

Stu