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Discussion Starter · #1 ·
Hello All,

I have run into a brick wall on this: when I try to start the engine on my 1986 Spider I sometimes get no spark and at the same time I get no fuel from the injectors. Other times when I try starting I get both spark and fuel -- its not consitent.

So far this is what I have done:
-cleaned all grounds.
-checked all fuses including the one located at the main and drive relays.
-ohmed out both flywheel sensors and got 1020 ohms on both.
-cleaned all connections at alternator, starter, coil and junction box.

The battery is new and I get 11 volts when I crank the engine.
I can hear the fuel pump coming on momentarily when I turn the key.

How do I check the the main and drive relays?
Could this be a problem with the key switch, if so how can I test it?

Thanks for your help,

Galliano
 

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Lots of good L-Jetronic info here:
Free troubleshooting Technical Articles

the main relay, smaller of the two under the rear parcel shelf. Same as one of the other relays in the car. The horn relay???

warning!
do not connect any kind of active/powered test equipment to any of the ECU connections.

passive test lamp or voltmeter only - no ohms

five contacts:
# 30=12v unfused input from battery, 12v should be there all the time
#85 = Drive system, output, end of winding negative or ground (connects to Fuel ECU terminal 28 and Drive relay terminal 31)
#86= Drive system, input start of winding, other side of coil (from Ignition ECU terminal 10, via Drive relay terminal 15)
#87= 12v output(s), (2) one each to Fuel ECU terminals 10 and 29
#87a= 2nd 12v output(s), (4) one to each injector

I have seen two schematic representations of the main relay. One where the 87 and 87a are internally hardwired together and another where the relay must make two output connections. Test both outputs!

See the attached pdf drawing.

The drive relay, fuel pump relay, or tachymetric relay because it receives a signal from the coil and will keep the fuel pump energized as long as it receives that signal (the engine is running).

7 contacts, only 6 are used.

#30 12v fused power from the battery, should be 12v there all the time.
#31 return direct to battery, (not always direct to battery but could be switch connected to return to battery) Connects to Main relay #85 and Fuel ECU #28.
#50 Starting Motor Control - direct. Connects to Ignition ECU #4, Fuel ECU #4, thermo-time switch, and cold start injector
#31b Return to battery negative via switch or relay, this connects to the negative side of the coil and gets pulled to ground with each sparkplug firing providing the tachymetric signal to keep the relay energized.
#87 12v output,
red/white wire to fuel pumps
yellow/black wire to Aux. Air Device
yellow/black wire to O2 sensor (heater)


Also attached is a cross reference sheet for the main relay, not confirmed! And an old Alfa Digest clipping on Alfa/Din codes.
 

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Discussion Starter · #3 ·
Thank for your reply 86 Spider.

Lots of info and I apreciate it. I'll go through all this stuff and let you know how I make out.

Again, thanks for the article and .PDFs.

Galliano
 

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Please keep in mind that the fuel ECU gets it's 'engine running', or RPM, signal from the coil negative terminal. If there is no spark then the fuel ECU thinks the engine is stopped and will not pulse the fuel injectors. In other words, if there's no spark, there's no fuel injection.
Diagnosing for no spark takes priority with the flywheel sensors topping the list.
 

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Discussion Starter · #5 ·
Thanks for the input papajam.

After reading your response I went ahead and decided to replace the coil with one I had from another project and sure enough I got consistant spark and fuel at the injectors. I put her back together and she fired right up.

Now, she starts right up every time I turn the key and don't have to keep cranking the engine.

Thank you all for your help. As always help from board members really helps.

Very greatful,

Galliano
 

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it's almost a alfa romeo spider
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86 spider. i tryed to open the pdf files.. no love.. code was broken..
 

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86 spider. i tryed to open the pdf files.. no love.. code was broken..
b1-
Must be just you gettin' no love - I had no problem reading the files, and I only tryed one tyme. ;)
 
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