I pulled the jetronic from the 82 this morning and was wondering if there is a way to ensure this is still good?

 

L-Jet Connector

This is how the system works. AFC [Air Fuel Control] relay XVI pin 30 always has 12 Volts regardless of ignition switch position. The AFC relay switches between pins 30 and 87, and the 12V at pin 87 then goes to the fuel injectors.

a. Measure voltage at pin 30?
-- If 12V present, next (for all test cases below, have the ignition turned on) is there 12V at pin 87? If yes go to (b)
-- If no, check the connection at the battery. A direct cable connects the battery to the AFC relay pin 30. Is there 12V at AFC relay pin 85? If there is no voltage, the ignition switch could be bad or the path between the ignition switch and AFC relay has an open or short circuit.

b) is there 12V at the fuel injectors (pick any one to check)?
-- If yes, this says that your problem could be with the fuel injection "ground" path. Go to (c)
-- if no, there is a wiring problem between the AFC relay and fuel injectors.

note: it may be confusing to see 12 V at both sides of the fuel injectors. The reason is when the engine isn't running, the circuit is open from the L-Jet module pins to ground. So with very little current flowing there is no voltage drop across the fuel injectors.

c) is there 12V at L-Jet connector pin 10 and 29?
-- if no, there is a wiring problem between AFC relay pin 87 and L-Jet connector pin 10 and 29.
-- If yes, check grounds for the L-jet controller. L-Jet connector pins 5, 16, 17 and 35 should have a very low resistance (via ohm check) to ground. For this check, set your VOM to Ohm mode and measure the resistance between the L-Jet connectors and a ground point on the car. If the Ohm reading is high to infinite, there is a wiring or connector problem with the ground points.

If all tests show OK, the L-Jet could be bad.

L-Jets are pretty reliable systems. As with any other system, the majority of problems in no-start or hard start situations are bad or non-existent signals from sensors or no voltage due to relays.

 

thanks Rez, kinda hard to test functionality when the motor is toast, I was planning on passing it on to someone who may be able to use it, but don't wanna send it to someone if it doesn't work

 

With so many 928s, don't you have another you can test it in?
Or another close by to put it in?
Bring it to the Frenzy and have it test in another 928 there....

 

Stan, this is the only one I have that has the control unit, I've got it packed up and bringing to Frenzy in hopes someone will be kind enough to hook it up and test it in their shark..

 

Sounds like a plan!

If someone wants to buy an '82 928 (non-S) with a very nice green exterior and tan interior, I would tow it down, and you could test it in that car. It does have some issues, but I am offering it for $3500. Otherwise it may become my sleeper street car!