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Discussion Starter #1 (Edited)
My '87 Spider had been running well after fixing an intermittent start problem in October. (cleaned the grounds)

Yesterday, cruising at 50 mph, the car shut down and refused to start, resulting in a tow home.

The fuel pump relay activates but do not hear the initial run of the fuel pump and no voltage to fuel pump on initial turn of the key. Also, appears I have no spark.

I went through the checklist in October; Can anyone save me some time?

Fuses 5 and 8 good, good fuse at fuel pump relay.

Full disclosure: Replaced clutch slave this week. Hit one of the flywheel sensors with ratchet, busted off part of the plastic. Car started and ran fine for 100 miles after.
 

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L-jet is a system - all the bits have to work for it to work at all. From what you've told us, the first thing to check would be the flywheel sensors. If it's loose from the bellhousing it won't sense properly. No sense = no start.

The next thing to check is the fuel pump fuse. It is an in-line fuse located next to the FI computer (under the shelf behind the seats). The original was a bullet type fuse. These are known to look OK but still fail to pass electrons. Replace it with a blade type fuse holder.

The only time our Spider had to be towed home was when it died as I slowed for an intersection. Turned out to be a faulty flywheel sensor.
 

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Discussion Starter #4
L-jet is a system - all the bits have to work for it to work at all. From what you've told us, the first thing to check would be the flywheel sensors. If it's loose from the bellhousing it won't sense properly. No sense = no start.

The next thing to check is the fuel pump fuse. It is an in-line fuse located next to the FI computer (under the shelf behind the seats). The original was a bullet type fuse. These are known to look OK but still fail to pass electrons. Replace it with a blade type fuse holder.

The only time our Spider had to be towed home was when it died as I slowed for an intersection. Turned out to be a faulty flywheel sensor.
Thanks Eric. Flywheel sensors passed the Ohm meter check. I'll check the tightness at the flywheel. I'm getting power on both ends of the fuel pump fuse.
 

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The fuel pump relay activates but do not hear the initial run of the fuel pump and no voltage to fuel pump on initial turn of the key. Also, appears I have no spark.
No spark means no 'tachymetric' signal to the drive relay. The drive relay controls power to the fuel pumps.
 

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Discussion Starter #6
No spark means no 'tachymetric' signal to the drive relay. The drive relay controls power to the fuel pumps.
Hey Eric, How do I check drive relay? I replaced with a spare, no change.

Both flywheel sensors seem to be secure and passed the ohm test.
 

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Discussion Starter #8 (Edited)
What is needed to generate 'tachymetric' signal?

It passes the battery voltage check static and while cranking.
Both Flywheel sensors pass the test.
Juice at both sides of fuel pump fuse, yet no voltage to fuel pump when cranking.
Fuse box fuses 5 & 8 good.

(THIS TURNED OUT TO BE FALSE, did have voltage at fuel pump.)

Any other ideas?

Thanks, Mike
 

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I haven't learned of any good tests for the drive relay other than replacement if suspect.

But, there is supposed to be a bypass circuit that powers on the fuel pumps during cranking (to ensure they run while trying to start the engine). IIRC, it comes via a purple wire from the ignition switch (but I don't always remember correctly...).

And if you haven't done so, replace that fuel pump fuse - even if it looks/tests OK. When those fuses get old, I have had them look good but somehow fail to pass electrons.
 

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P.S. send BB member Papajam a PM and ask for copies of his color-coded wire diagrams for your model Spider. Include your email address - he'll send some .pdf files that make chasing Alfa electrons a lot easier.
 

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Discussion Starter #11
P.S. send BB member Papajam a PM and ask for copies of his color-coded wire diagrams for your model Spider. Include your email address - he'll send some .pdf files that make chasing Alfa electrons a lot easier.
With Jim's quick service, I believe I have a bad fuel pump. It looks original, recommendations; Delphi ok?
 

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Discussion Starter #12
New fuel pump

Yes, all good after new fuel pump. Lucky to have this 38 yr old part fail close to home. Fuel lines in sad shape too.

Was loosing confidence in Jetronic, but it was my sloppy diagnosis. Ready for road trip now!

Replaced with orig replacement pump from Quantum Systems. Very quiet, and lifetime warranty for $79.88 with shipping.
 

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