Ever been driving your 914 down the road and suddenly find yourself on the side of the road with your head in the engine bay, trying to figure out why it's stopped running? Yeah, sounds unlikely I know, it's only happened to me a few dozen times. Often, the cause is something very simple that if you just had a couple of tools, you could figure it out. Here are three I keep in my car that have helped me out more than once. The examples with links to Amazon cost less than $25 total.
Bosch "noid" light: unplug connector to an injector and plug the noid light into the connector, flashes if it's getting an injection pulse. If all four check out, your ECU, trigger contact points, and wiring harness/grounds are working. $6
https://www.amazon.com/OEMTOOLS-25141-Noid-...C/dp/B004FELH04
Firing indicator: Place grooved end against spark plug wires and coil wires, light flashes if you're getting spark. If they all check out, your dizzy, points, cap, rotor, wires, coil, and condenser (or your electronic ignition) are working. $9
https://www.amazon.com/all-sun-Portable-Aut.../dp/B013JGEWLY/
There are also fancier versions of the firing indicator that have LED's and a battery and cost about $30, IMO, it's wasted money, they don't tell you much more than the cheap $9 one does.
Multimeter: Mine is ancient but still works fine. I keep my fancy DMM's at home. You can test for tons of stuff with a multimeter. Check your battery, wire continuity, see if voltage is present, check bulbs to see if they're blown, etc. Indispensable. $7, you can spend more, but for quick diagnostics this is all you need. This one has cheap leads, if you want to spend more, buy some decent leads.
https://www.amazon.com/General-Hand-held-Mu.../dp/B00066ZZO4/
Here's a pic of my set of these tools, had them in my glovebox for the past 20+ years. I also have a spare clutch cable and throttle cable in the well of the spare in the front trunk, as well as tools to install them if needed. Also a full set of fuses and a spare relay in the glove box, too.
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