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Discussion Starter #1
Hello,
Going thru troubleshooting of a no-spark problem -- all of the sudden car in the garage not starting.
Initially I thought was Fuel Pump -- did not hear the buzz.. then I thought was the Start Relay.. I bypassed it and fuel pump(s) both start and work fine..

Checked spark-plug when cranking -- nothing!
Battery is at a solid 12.7 when cranking.

Voltage at the ignition coil with the ignition ON is only 7 V ....while I read 12.5V at the battery.
Can that be the problem ?? And What is the next step?
I do have another coil but if I don't see 12V at it now I would assume the issue is upstream??

Thank you!
Giuseppe
 

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a good thing to do, is replace the oem dizzy with a aftermarket dizzy. i know where one is with the correct coil and a timing light. the aftermarket dizzy has a better advance curve, so it will make the cat acell. faster. just an idea... also you should only work on your car when it is above 100 degrees:cool:
 

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hey..my car was running for 15 years before i took her down,, no changing the coil will not help..you are still only getting 7 volts to it
 

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where are you measuring 7V?
if you measured from coil positive (15) to ground, then yes I'd expect to see battery voltage or close.

the voltage to coil comes from the hot side of fuse #7
Perhaps check at the rear of the fuse box if that connection is tight and secure
 

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I would do a test on your crank sensors next or if you have a spare known working computer try installing that and see if you get spark again.
 

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Discussion Starter #7
I would do a test on your crank sensors next or if you have a spare known working computer try installing that and see if you get spark again.
Hello! I did the crank sensor L-Jet test on both the sensors. I see 1000 ohms at the right most pints. Is there any other test I can do ?
 

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Discussion Starter #8
where are you measuring 7V?
if you measured from coil positive (15) to ground, then yes I'd expect to see battery voltage or close.

the voltage to coil comes from the hot side of fuse #7
Perhaps check at the rear of the fuse box if that connection is tight and secure
If I measure with ignition ON coil positive to engine I see about 10.3 V ( battery I see 12.5 V). If I measure coil positive to coil negative I see 7 ~ 8 Volts.
 

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Discussion Starter #9
where are you measuring 7V?
if you measured from coil positive (15) to ground, then yes I'd expect to see battery voltage or close.

the voltage to coil comes from the hot side of fuse #7
Perhaps check at the rear of the fuse box if that connection is tight and secure
Yes... that is my next focus. I need to see 12V at the coils! I inspected the fuse box area... Man what a joy! Found 1 damaged thick single red with fried duck tape that I repaired properly (no change), and 5 cut wires under the steering column from POs.. with wires that I have no idea what they do.
 

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... with wires that I have no idea what they do.
Do you have a copy of Papajam's (RIP) color coded wire diagrams for your Alfa?
If not, let us know. I'll send you copies that will make chasing Alfa electrons a lot easier.
 

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If I measure with ignition ON coil positive to engine I see about 10.3 V ( battery I see 12.5 V). If I measure coil positive to coil negative I see 7 ~ 8 Volts.
well I would expect to see near battery voltage from coil positive to ground (engine)....so you are only a couple of volts down.

what about your battery ground? Where it is bolted to the trunk floor? is that clean, secure?

The measurement you did, voltage across the coil (+ to -) doesn't really mean anything.
(I have never measured, or heard of, measuring voltage like that!)


what you need to see is the pulse.....ie. if you put a little test light between coil + and coil - and then crank the starter, the test light should flash (signal)...my guess is it doesn't.
and that pulse is controlled by ECU / flywheel sensors and likely tied in to that drive relay
 

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Discussion Starter #13
Hello.
No spark confirmed.

At the output of the coil to the distributor I see a 17.5v Max registered by the voltmeter. Is that good??

The test light across the + and - of the coil is steady on pretty dim not flashing.

Looked that the distributor and cleaned the contacts.. seems OK.
 

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Discussion Starter #16
Update.
Followed Ignition wire to ECU. Cleaned connectors behind the glove box . Interesting the car last week was under a major rain for about 30 minutes, with water dripping in by the passenger side glove box area (kinked drain hose)..

Now.. following the schematics I found the connector the goes to the Ignition ECU behind the glove box.. Found the 12V and checked it at the ECU connector -- pin 10 -- looked good 12.5 V with ignition on.

Did not notice any moister anywhere -- just dust.

Could it be the Ignition ECU ???? dead all of the sudden ? Any way to check that ?

Any ideas what should I look at next ??

When I turn I hear the relays clicking and the fuel pump in the tank. And when I pulled the spark plug it was wet.. and I did try bypassing the relay -- the problem is no spark

Maybe I could swap the Coil _ I have another one...

Grazie
Giuseppe
 

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Discussion Starter #17
IT"S ALIVE!!!!

So tried to crank without the Seat belt relay and the wiper relay and it started!

THen of course I re-attached one by one... and still worked . What I did to get it back alive was:

1- Cleaned connector G121 that resides behind the glove box
2- Cleaned the points of the wiper relay
3- Disconnected and re-connected Ignition ECU relay to check pin-10 Voltage ( and sprayed some cleaner )

I highly suspect the rain must have done something ?? I cannot believe that the car did not work AFTER about 5 days...

Thanks everybody -- learned a lot about the electrical system of the 82 Spider... I have some more clean up and fixing to do by the fuse box.

--Giuseppe
 

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Well done:)

"If I measure with ignition ON coil positive to engine I see about 10.3 V "

just to wrap things up, could you once more do that exact test and let us know the difference now?
Thanks.
 
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