Quick background: Bought the car in February, has sat for 1.5 years estimate. Fuel pump and sock rotted out along with the original fuel pressure regulator. Those have been replaced and the fuel pressure is great at 39psi when starting. Fuel filter has been replaced. The primary injectors have never released fuel for me. Fuel does get through the whole rail and out the pressure regulator.

I just had all of my injectors cleaned through rc engineering and they came back showing great test results on paper.

Plugging them into my fuel system however, the primaries failed to release fuel while cranking the engine as shown here:



As you saw in that video, I tried plugging the secondary injector to the primary plug and it worked wonderfully. This meant that there is pressure at the secondaries. Since the secondaries are after the primaries by nature, the primaries have the same pressure.

Please view the pictures to see the fuel rail setup, that the primary fuel block/rail is not clogged (pic taken before eliminating the fuel pulsation damper), and the injectors after being well serviced (new o rings and filters for free!).

Now, please view this video which proves that the pintle is not opening as I press on the primaries with no reaction while pressing on the secondaries releases a thunderstorm of gas:


RC Engineering has been very helpful on the phone and suggested that I send them back to be re-cleaned and tested which is what I am doing. I am also sending them the fuel rail to be sure that it isn't the cause.

To help the process go smoothly, I am requesting any help you may have. Is it possible that the injector filter/opening is not aligned with the opening in the primary fuel block? I measured the distances and noticed that the injector opening would be lower than the center of the opening in the fuel rail. This is a stock fuel system though so that shouldn't be a real thing.

Thanks in advance!

 

They could just be stuck, sometimes after cleaning the cleaning fluid sits and makes the tip stick.

Try applying 12v and ground to the two electrical contacts of the injector and "tapping" the signal. So, you'd have ground with an alligator clip to one contact on the injector, positive going to the other and take the positive wire and tap it on the battery. That will cycle the injector full open and full closed. May also want to spray some WD-40 or PB Blaster on the tip of the injector.

You've had some good troubleshooting, you've ruled out everything but the injector. I think it's just not opening.

Dale

 

Those pintles should move freely up and down about 1mm, however for them both to be seized that's a bit weird... maybe RC stuffed up and sent seized ones back instead of the cleaned ones?????

I'd only say this is the case if you had cleaned them and left them for two plus years, and a company like RC Engineering would be utilising injector parts cleaner which is basically petrol anyways.

2 things kill injectors, debris in the pintle solenoid, causing it to either not open or not shut, and corrosion - typically from water/condensation that occurs if petrol is left stagnant for a long time.

I clean tonnes of injectors and 90% of the time with RX7 injectors its the secondaries that are problematic, so for 2 x primaries to not be working it's definitely odd ball

 

I second what Dale said. I had my injectors cleaned when I rebuilt my engine. They sat for a few weeks while I finished the rebuild and when I finally installed them and tried to start the engine, I had no fuel.

After a long a frustrating troubleshooting process, I finally pulled them back out and applied power directly to each injector using the tapping method with a 9 v battery and alligator clips like Dale describes. Both primary injectors were not clicking when I applied power. In order to free them, I had to apply power while tapping on the body of the injector. This process successfully freed up the pintle. You should be able to feel and hear the pintle move when you apply voltage to the injector. My injectors have been working flawlessly ever since I performed this procedure.

Good luck!
Alex

 

You guys are awesome thank you!! I needed your help to be sure that I wasn't causing the problem.

Turns out, they somehow became stuck after being cleaned. I sent them back to rc engineering after the first time, and they were very very helpful. They recognized that the primaries became stuck somehow. They then cleaned every injector again and then the fuel rail to be extra helpful! They even then checked the injectors in the rail to confirm function before sending them back!

Here is the video from tonight of the injectors working as they should. Big relief!


Now I will solder on new primary plug pigtails since they were fraying. Then it will be reassembly and maybe, just maybe a successful start!



In summary: Stuck injectors originally from old sitting fuel, cleaned twice, now work wonderfully.

I highly recommend rc engineering!

 

Wow, looks like you were right Dale and Alex! It's always good to learn new things and I've been cleaning injectors for about 7 years now :-D

Great that RC were so helpful, and awesome to have the problem solved ay.

 

Were you able to get the primary rail off without removing the OMP line? Mine is RIGHT in the way of bolts that hold the primary rail on.

 

Yeah mate you can be gentle and push the omp line out of the way just enough to get to the bolts and remove the rail, pull it back towards the lim