924Board.org

[ED.]

Hello to all I have a question about a 1981 NA 924. The car was bought not running (probaly not a good idea but, want to make a good go at it before throwing the towel) I have good ign. module that is not sending any power to the distributor when cranking over. I'm not sure where to begin I am very good at mechincal repairs and fabrication (years of 240 Volvo ownership) although lacking in electrical ability. Any advice and some positive encouragement is greatly needed and will be appreciated. Thank you.

[Lizard]

ED,
for starters if the car hasnt been run in a few years and this is why it isnt running, well lets just say that before you try to start the car you should pull out and clean the gas tank, and possibly prepare for a new fuel pump soon, as well as possibly flushing out all the CIS componants, or consider converting to EFI with megasquirt.

as per the Ign, how do you know that the ign module is good?

in regards to the ign not providing the coil with power, the ign module is supplied with a 12V switched ign source, however this ONLY recieves power when in the ON position, there is another circuit (50) which supplies power directly to the coil while starting, this wire comes off the 3rd post of the starter. (you could also run a wire directly to the ign module for testing only)
it is also possible that the ign box isnt being triggered due to a defective green wire running between the distributor and the ign box, to test that you would disconnect the wire from the distributor and the try to tap the 2 wires in the plug together with a wire, if you get a spark then you know it is the trigger in the dizzy, if you dont you can try to tap the 2 together at the ign module and if you see a spark you know that the trigger wire is defective,
the other possibility is that the Ign wire running between the coil and the ign source is defective, by factory this will be a resistored wire (1 ohm) so you cannot just replace this wire with a direct wire, you will need to get a 1 ohm resistor to install in the middle of that line.
but it is also possible that the ign module isnt getting a good ground, so you may consider getting a test light and running the test light between the ign module plugs positive and negative terminals just to verify that you are getting both - and + there however consider using a test light that puts a light load on it so you can verify that the circuit doesnt go dead when a load is put apon it,
also I would verify that the coils resistances be checked to verify that the coil isnt defective if you have not done so already.

one other note is that you may consider replacing the factory ign module with a good CD unit (MSD), however if you do do this you will have to use a switch for the fuel pump as the fuel pump gets a tach signal from the ign system to turn on, and the tach signal (though the tach still works) has a different ossilation (probably spelt wrong) which the fuel pump relay doesnt read as the ign being operational. or possibly wiring up the fuelpump to work off a standard X relay.

good luck with it. welcome to the board, but please RTFAQ.
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3 928s,

[Neil924]

[Lizard]

hey Neil RTFAQ is a standard abbreviation on all forum boards,
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3 928s,

[gohim]

Lizard.

The ignition wiring is completely different on a 81, and different problem could cause a "no start" on a 81 and later car.

But you did ask some good questions.

#1 being, how do you know that 12V is being supplied to the igniter module, and how do you know that it is good?

There are several possible areas that could cause a no start problem on a 81 or later. I found that corrosion of the connector pins on the idle stabilizer was causing an intermittent problem on my 81. Bypassing the idle stabilizer is the first thing that I would try to get the engine started. The idle stabilizer is a black plastic box mounted above the igniter module located on the left front inner fender. You can bypass it by unplugging the two round connectors on it, and plugging them into each other (you can also disable it (you must do it this way while tuning the engine) by unplgging the single spade/quick connector at the top of the left inner wheelhouse/fender.

The next possible problem is the breakerless ignition module located inside of the distributor. In my experience, this type of Bosch manufactured module is good for around 100K miles, after which they can go intermittent, with the engine dying (and usually able to immediately restart), and after that stage dying completely. I have had the same type of distributor ignition bmodule manufactured by Bosch die in four cars from four different auto manufacturers. The module can only be replaced after disassembling the distributor, which requires a press to disassemble and assemble, meaning time to pay someone to do the work.

But don't get ahead of yourself. The first thing to do is make sure that you are getting gas in the cylinders. Remove the air filter, and one of the four fuel injectors. Place the fuel injector in a deep clear (preferrably) clear glass bottle. Have someone turn the ignition key, while you reach into the air cleaner, and gently raise the air flow sensor arm, and watch for a fan shaped flow pattern from the fuel injector. No fuel means you have a clogged fuel system, defective fuel pump/s, bad fuel pump relay, or clogged injectors. Test all four fuel injectors, one at a time.

Good fuel flow? Now you may have a bad ignition system.

[ED.]

Thanks to all for the suggestions I shall try them all out over the next week or so. I had the ign. module checked at a local parts store. I will go thru the Faq's I will keep you all posted and probaly beg for more help.