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Discussion Starter #1
I just purchased a 1986 Veloce. I am not new to cars or motorcycles by any means and I just finished my big bore Harley engine so now it's on to my next project however, with that said I am new to Alfa's. The car is structurally rust free considering it's a Pennsylvania car. It was last inspected in 2008. We bought it as a weekend driver and Auto-X project. First thing I noticed was that the distributor cap and rotor were removed from the car but inside the engine bay. Neither appear to have much wear on them so I replaced them and put a battery in the car. We were able to get the engine to hit momentarily but determined the in tank pump and sender were bad. I ordered a new setup from Centerline. This was this passed Fri. We spent Saturday gutting the interior for fresh carpet and seats. Yesterday I wanted to see if the engine would fire on some ether but now we have no spark. What would potentially cause the no spark issue in a matter of 2 days? I'm not sure where to start and don't want to throw money at this trying to find something wrong. Coil reads 12 volts at the green wires. Battery is also reading 12v constant with ignition on. One thing I did note is a bit of rust inside the distributor itself below the plastic disc that sits under the rotor. Thanks in advance for your expertise.
 

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No spark could be a lot of things, including low battery voltage (although 12v should be sufficient while cranking) or bad flywheel sensor(s). There is a diagnostics manual at this link, where you will find a lot of great information about how to test the various components of the Bosch L-Jet system.
 

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Discussion Starter #4
Thank you! I'm really curious if going to a "standalone" distributor such as an RML would also alleviate some ignition issues? I basically did the same thing with my recent HD build and used a digital ignition that allowed me to delete the factory ignition setup as a whole and used a lot less wiring. Are these RML units the same way?
 

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I would try a healthy battery first. I full battery should read in the 12.6 range, and 10.5 minimum during cranking is required to signal computers to furnish spark and fuel. It might crank over just fine but not enough left over voltage to wake up the computers.
 

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Thank you! I'm really curious if going to a "standalone" distributor such as an RML would also alleviate some ignition issues? I basically did the same thing with my recent HD build and used a digital ignition that allowed me to delete the factory ignition setup as a whole and used a lot less wiring. Are these RML units the same way?
You can just delete the whole ignition computer by going with a different system but I have found the Bosch system to be quite robust when operating properly.
 

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And check your fuse contacts as well as the battery voltage under load. Depending on the circuit, corroded fuses or corrosion on the contact tabs can affect both fuel and ignition.
 

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Discussion Starter #9
I am going out on a limb assuming. I picked the car up off a guy who was won it in a settlement over a services rendered but not paid for scenario. He unfortunately didn't know anything about the car or it's history. Being the car was running in 2008 I'm going to assume it stopped running or started running poorly and the first thing they figured to do was a simple tune-up. Giving up after that didn't work. I ordered 2 new flywheel sensors and a cap/rotor irregardless of what the current one looks like. All of which weren't too bad. Both sensors are Bosch units at $115 for the pair on Amazon. Going to use my battery booster to get some voltage up as I have had the car switched on and off while chasing some other gremlins. It's my understanding these need quite a bit of voltage during cranking to get the ECU to respond.
 

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Discussion Starter #11
Tested the ignition coil resistance low side 0.9 ohm and high is 3,950 ohm. I believe the low side is in spec but the high side seems pretty low in resistance. Any suggestions?
 

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Cardisc (no affiliation) has a DVD factory manual with just about everything you will ever need. I highly recommend it, as I am sure others will also.
And welcome aboard
 

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Tested the ignition coil resistance low side 0.9 ohm and high is 3,950 ohm. I believe the low side is in spec but the high side seems pretty low in resistance. Any suggestions?
looks ok to me...in any case that test, whether your readings are high or low compared to new specs, will not tell you much about a coil.
Jetronic
Primary 0.6~1.0 ohms
Secondary 3.0~5.0 K-ohms

you have got 12V at the coil positive to ground.....
(I'd be happier if it was over 12v....so whilst waiting for parts get that battery on charge!)
Remember too, you need a minimum of 10,5 V 'during' cranking, or the ECU will simply not work.
So test that and report back (just put voltmeter on battery, then have someone crank the engine)
If that is good then look for a tachymetric signal:
when you crank the starter, does your tach needle move slightly?..no signal, no spark.
If no, then one or both flywheel sensors are suspect.
 

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It does move slightly during cranking. Like a tick up and down.
odd, because then you should have the tachymetric signal.
you probably tested for spark at the leads, but is there spark at the coil itself?
see:
How to test my coil pulse

if yes then check
the rotor arm is seated properly
distributor cap is correctly seated
HT lead is firmly seated in the coil centre post and the distributor centre post
4 leads correctly pushed into the cap
 

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Discussion Starter #16
Got some parts in the mail. Put new cap, rotor and wires. Still no spark. Tach jumps to 3k when you first turn engine over then back down but continual cranking doesn't not cause the tach to move after the first time
 

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I'm thinking you have a bad ground somewhere. These cars are really picky that way. Main battery ground, grounds on intake manifold, etc.
 

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If someone has been inside the cam cover make sure the 2 rear hold down bolts are the ones with metal washers, there are only 2.
 

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we need to know the cranking voltage...
 
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