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Discussion Starter #1
I have an '87 spider that runs great. But, occaisionally, it will not start. I have a strong battery, it cranks strong, 11.7+V at the coil, but no spark. I can crank until the battery is dead, and the next morning, with practically no battery, it will start on the first crank. There seems to be no pattern to when this will happen, although it has never happened when the car is turned off for only a few minutes.

Has anyone had a similar problem and figured it out before pushing it off of a cliff. I love this car, but I'm beginning to look for a cliff!

Bill
 

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1966-2013
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Are you sure it's no spark as opposed to a lack of fuel?

Do you hear the pump(s) hum for 1/2 second or so when you first turn the key on?

Have you looked at the plugs to (1) see if they're wet with fuel after a period of no start and (2) that they spark across the gap when holding one on the head with it connected to the plug lead while you crank the engine?
 

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Check the Ohms of the coil to ground.

Check the resistance Ohms of the coil to dist cover wire.

check the resistance of all the plug wires.

check the rotor, the dist., and that the black button is still in the top of it.

where are you not getting spark? at each plug?
 

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And Bill...trust me, I've been there. It's not just Alfa's, it's old cars in general. Weak grounds, corroded wires, parts going bad.

Just slowly trace your way back from each plug, make sure you are getting spark at each plug. Assuming your plugs are good too.

check your battery ground strap too - might as well loosen, clean, dialectric grease and retighten each connection
 

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Discussion Starter #6
It's definately no spark. I hear the pumps and I have fuel. I get no spark at the plugs and no spark from the coil to the distributor. I have over 11.7V at the coil, it drops to about 9.5V during the cranking.
 

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It's definately no spark.
As long as you're postive. :)

I have over 11.7V at the coil, it drops to about 9.5V during the cranking.
And there ya go.......

L-jet requires a minimum of 10.3 volts during cranking the even 'wake up' and start making all the go-vroom signals happen. (like turning on the seperate ignition control box for one)

Get after the grounds, fuses, etc until you get the proper voltage during cranking for starters. Otherwise you'll just be defeating the purpose of other tests.
 

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I think "technically" you need 10.5 volts during cranking, but as indicated, the car has started under even lower voltage.

Yes, test your battery.

If your coil is good (did you check resistance from a ground tab to center of coil - 9K-11K ohms), then you need to check that the coil to dist. plug wire is good (bend it around, check resistance).

Charge up your battery to 12.5 volts.

There are lots of things to look at - ignition switch, ECU. But battery and wires and plugs are all right there, easy to test. Once you determine they are good, we can move on.

You will get this sorted! :)
 

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Yeah, Bill, you're just going to have to work your way back from each plug wire, testing - plugs to wires, wires to dist, check dist and rotor, dist wire to coil, check coil, check battery more, check grounds, connections, check ignition switch.

Tifosi is very knowledgable on L-Jet systems. He is your man. Where are you located Bill?
 

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You must have 10.6 volts or so to the ignition computer for it to fire. Less and there is no spark. If your coil voltage is below 10 that is the problem.

I have 3 of these cars and one does this all the time. I check voltage and for some reason this one has about a 1.5 volt drop at the computer. With even a marginal battery, it doesn't fire. I've checked connections and grounds repeatedly but never found the exact point were the problem is.

Bosch (and others) has a replacement brush-voltage regulator module at 14.5 volts. The standard is 14. This fixed mine in spite of it.
 

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Discussion Starter #13
Thanks all, given the intermittent nature of the problem, I will have to wait for it to happen again. Right now, it's a new day and the Alfa is a machine! Do you have any idea why I might get a higher voltage drop during cranking on some days than on others?

By the way, I'm located just outside of Philadelphia, PA.

I will report back with what I find. Thanks again.

Bill
 

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Oh, it could be anything from a battery starting to 'go bad' and reacting to overnight ambient temperatures, poor grounds not allowing for a proper re-charge while you drive, short hops that will never get the voltage back up, a starter motor that draws more juice than it should, some timer or intermittance that doesn't turn off as soon as it should (curtesy lights is a great one for silly stuff) making for a longer term draw, dirty terminals, dirty/poor grounds, phases of the moon and even how many chickens you sacrificed to the proper gods on the correct day of the week. (Tuesdays are right out, and never a Rhode Island Red in any instance)

Me, I'd lean heavily toward grounds (clean and polish every one you can find), *battery terminals, (clean and polish), just general resistive corrosion on any wire in there (every wire you ever work on or get near should be cleaned and polished whenever you're near it), and mabe a touch of ignition switch going wonky and/or fuses acting stupid ('specially if they are bullet style. Them things can go bad on a whim even when they look brand new)

*depending on how old the battery is, or how many winters it sat over in storage, a load test wouldn't hurt a bit.

Primarily though, the greater majority of the problems with the L-jet are relative to grounds and/or wire connections in general.
 

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Oh, no, you're not gonna make this my fault.

Let's wait for ghnl to show up, then we both have someone to blame...
Umm, sorry. I am on vacation. Y'all can't blame me.

First I got to play 'pit crew' for a friend who was racing his 1959 Giulietta Spider at Lime Rock, CT. Now I am at our daughter's house in Masschussets playing Grampy with grandson (yes I is that old...).
 
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