I have a US spec 84s and I've recently replaced the fuel injectors with new ones from Roger at 928srus. The car started and ran (not smoothly, hence the new injectors), prior to the installation. Now, the cold start injector fires the engine, but it immediately dies out. Has good fuel pressure, no leaks, new fuel filter, etc.

I'm wondering if the new injectors are not the same as the old ones, and I need to somehow train or reprogram the ECU?

Thoughts?

 

Proper replacement injectors should be plug and play....no other changes required.
These older cars have a tendency to have deteriorated wires that go to the injectors...the insulation falls off the wires, right near the actual plug (sometimes under the protective boots.)
If this is the case, the power wire and the ground wire to the injector can short out against each other.
This will stop all of the injectors from firing.

Carefully check each injector plug-in for this "shorted" condition.

 

otherwise PRIOR to installing new injectors they should be checked for operation ,
you can use a 9 volt battery and an AMP 2 pin plug ,
make sure the injector clicks when the wires are touched to the battery.
NOTE put a drop of PB blaster in each one for storage.
If the injector wont click,
add PB then gently tap tap the inlet side square onto a block of wood a few times,
this should shock the injector

 

We check them all before shipping - at three different pulse speeds.

 

Thanks for the follow up.
I checked each injector (and I hear the click). I also checked each harness for continuity, and we're all good there. I checked the fuses and relays, and jumped the fuel pump and checked for leaks/pressure. It holds at ~2.3-2.5 bar at the fuel rail.

I'm contemplating switching back to the old ones to see if they fire - if they do, then I'll be REALLY confused...

Any other thoughts?

 

I'm sure that Roger would be providing the correct pieces, but you might double check the resistance or the injectors.
High impedance or low impedance?

 

An update...

I changed out 4 of the injectors to the best looking old ones (I haven't tested/cleaned the old ones).
Fired right up! Still running rough. Here is a picture of the existing and the new one(s). They ends look quite different and I'm curious if these are somehow the wrong injectors for my car. Roger is always on top of it, so I maybe sent the wrong info?

Thanks

 

Call Roger?

 

Either email me or let me know your name please?

 

Thanks. That was my next step. Roger, I'll shoot you an email.

I appreciate allmof the help and insight.