Holley efi (model 502 analog system)

[Ken-Arne Jensen]

Hi Tom							Aug 22


> Here are some notes about the way the Holley ProJection system
> works.  I'm slowly reverse-engineering it so that I'm not
> left stranded (like I am right now ..... with an injector
> that doesn't work and don't know where to get another $69 from
> Super Shops).
>=20
> I've heard that a standard Bosch injector works but I don't
> know if that's true or what part number.  If someone knows any
> more info on this, please let me know (I need one yesterday !!).
>=20
> The injector measures 1.8 ohms resistance (well, the other one
> measured 7.4 ohms, 332 ohms, 1.5 ohms, open circuit, etc, etc)

I had the same problem when I got my Holley 502-1 system some years ago.
One of the injectors wouldn't fire at all, and had different readings
when I tried to measure the resistance with a multimeter.

You should check the soldering on the connecting pins on both=20
injectors. The connecting pins on the injector have a
small (copper I presume) wire inside of a metallic tube (~1 mm).
The fabric soldering on one connector pin didn't have good contact with =
the=20
wire inside. So the fix was simply to use a small file on the tip=20
of the connector pin tube, and resolder each pin.=20
I did this for all connector pins just to be sure :-).=20
This was back in 1993, and the injectors  have worked fine since.

I also had a stuck open injector later on, but that was due to a
defect ECU (that Holley replaced without charge). It was a quite amazing
experience :-( , beleive me. You drive normally and suddendly one =
injector
stick open, the engine bogs and finally stops, and when you switch off =
the
ignition and check under the hood, it is gas everywhere.
I later found the reason, Because the injectors on a TBI are placed =
above
the throttle plates, and you let off the foot when the engine
dies, but wait a bit before you switch of the igition (and the pump),
the gas fills up and float around on a hot engine. I think I did this
test run without an air filter too, and this helped of course :-).


//// Ken-Arne Jensen              // E-Mail: ken at staff.cs.uit.no         =
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