1975 csi injector familiarity

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Hi folks, I have tabled my project for the past week. Life got in the way.
Last update the AAV wasn't functioning, that I believe is satisfied. I decided to use injectors that haven't been fired in 30 yrs almost. I power tested them on a bench, they all pulsed, so I gave it a shot. Two injectors didnt spray fuel. I decided to purchase rebuilt injectors on eBay and replace all 6. Here is what I got
5 that look like this

And one that looks like this

They were listed as standard fj709 as I believe the car calls for.
Should I be concerned about the difference ?
I have seen both styles in other photos. Ideally I'd prefer them to be identical ,
In my experience with modern cars an aftermarket injector can often appear different from original and cause no problems.
Any thoughts? Fred
There is power to the dead injectors.
Fred

 

[sfdon]

How's the car run?

 

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It's running on 4 cylinders. But I haven't put the new injectors in yet. Don, are you familiar with both style injectors? Fred

 

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I do have 150 (+--)

 

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Compression across the board. Very close in readings in all cylinders.

 

[sfdon]

Disconnect those ASAP and just get the right ones.
You can read the number on the old ones and call Robert White jr at FI corp for the ones you need.

 

[sfdon]

Just re-read your post- looks like I missed your point.
Will the odd one even fit?
You need to tell seller you want matched set.
What number is on the old injectors and new injector and the odd one?
What resistance in ohms ?

 

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Still struggling to get this car to run well. I haven't had a ton of time lately. But here's where I'm at. Brief re-cap: 1975 csi car, motor block and head from 77 530i. All egr eliminated. Both manifolds, exhaust and intake original to car. Car has been dormant 30 years. I am by no means an expert. I don't have any experts near me. I plan to refresh original motor and drive the car for now.

The car runs horribly, I have since re-cored radiator, believe to have good coolant flow. I have tried original injectors, then new injectors. Not much difference in running performance. Timing, ignition,plugs, points, wires believed to be good. Engine compression excellent. It is running so poorly I feel only three cylinders are firing, hard to tell. Easier to isolate one if it were 5 firing. I eliminated the cold start injector and plugged the vacuum hose going from cold injector to the AAV. I did this to attempt to zero in, as the cold start system is of zero value to a running engine (I think). I have about 30psi fuel pressure at the cold start fuel line. That leads me to believe fuel pressure throughout is 30psi as the cold start is near the end of the fuel rail loop. I think the car calls for about 30psi.

Suspects in my opinion:NEED HELP

1) poor voltage coming off injector wire plugs. I am getting less than one volt pulsing at injector plugs. HOW MUCH VOLTAGE IS REQUIRED.? I DO GET ABOUT 12v at cold start injector. BUT LESS THAN ONE VOLT AT CYLINDER INJECTORS. Is that normal? Do I have bad ground? Bad ECU? Or is (.4-.5v) normal.

2) possible but not likely injector harness plugs got mixed up between two of them? Would that even matter as the ECU sends fuel evenly.

3) what do I need to know about the manifold pressure sensor? Could that be malfunctioning?

4) throttle position sensor? I highly doubt that could cause poor running. I suspect that would make for a fluctuating idle if faulty.

5) manifold vacuum regulator pump thing. Not sure of actual name, but it seems to doing its job. If I unplug it car shuts off, and it seems to be pulling vacuum off manifold.

6) injector plug one specific way? The plug will attach to the injectors either way, they prefer one way more than the other, so I plugged them all in the same manner that seem more cooperative. Could they all be in reverse? Is there a specific signal to each injector prong?

7) week coil?

ANY THOUGHTS WOULD BE GREAT. FRUSTRATED IN MASSACHUSETTS.