Electrical Issue?

[Duffman]

Am working on balancing my SUs and after reinstalling in the car am having electrical issues (I guess). The car starts fine and then just dies. I notice the car idles fine and then the tach drops to zero and the car dies. Have not had this issue before. Have electronic ignition (E12-80) and using a Blaster coil. Seems like something electrical is causing it to die, not the carbs. Any thoughts?

[Duffman]

I should say that I have an ongoing issue with a bouncing tach, but nothing like this.

[240260280z]

I would guess that a wire between the distributor and the coil/ballast may have come loose or broke when the SU work was done.

A friend's 260z would randomly die and it turned out to be an exposed wire from the distributor that had it's insulation damaged by the fan and it would intermittently be blown by the fan wind when driving and short to the metal in the area and kill the ignition system. You seem to have a similar strange happening. Check the low voltage wiring closely at the distributor/fan area.

Edited September 4, 2011 by Blue

[Duffman]

Thanks, Blue, I gave it a quick once over before, but will look closer now.

[240260280z]

My apology and correction, the wires were not damaged by the fan, it was damaged by a pulley (back in 2007). Here is a photo of the damage:

Edited September 4, 2011 by Blue

[Duffman]

Checked the wires between the coil and distributor, no problems there. Checked the connections and tested the continuity, both seemed fine. Noticed some of the spark plug wires had a white corrosive buildup on the distributor ends, as well as the center distibutor to coil wire. Any reason I would have that issue? Replace the wires? Any other thoughts?

[Reverend]

How about fusible link? I had similar problems (with normal dizzy though) and problems were in ballast resistor (which you dont have i suppose?) BUT other option was fusible link. It is located next to starter engine. Some wiser can explain.

[Duffman]

Koalia, no ballast resistor, as you guessed. Will double check the fusible link by the starter, though a quick review of my wiring did not reflect any visisble problems. Thanks!

[Duffman]

Still scratching my head on this one ... wires seem to be fine. I can start the car, with choke, and it idles fine at around 2000 rpms. At running temp, I drop the choke down and the tach drops to zero and the car dies. It will start right back up, but does not maintain idle. Carbs seem to be fine, fuel pressure constant 3 to 3.5 psi. Any other thoughts? Should I look at my coil or distributor more closely? Coil is less than 1 1/2 years old, not used much. Would my symptoms have anything to do with the E12-80 module possibly going bad? This is not an area of expertise for me, as you can tell ...

Edited September 7, 2011 by duffman

[LeonV]

Hook up a timing light to see if you lose spark or if it becomes sporadic.

Does the car still run if you pull the choke off after, say, 30 seconds of running? Can you restart right after it stalls?

As a quick check, when this happens, spray the coil with freeze spray (or something similar) to quickly cool the component. If there is no effect, do the same for the ignition module. The point is if there is a heat-related failure with one of these components, this will diagnose it.

[Duffman]

Thanks, LeonV, will check it out and report back.

[beermanpete]

Are you sure you don't have a vacuum leak or an incorrectly adjusted float? It sounds like it might be lean at idle and when you use the choke it enriches the mixture enough to correct/mask the problem. Have you tried to drive the car?