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I changed out my voltage regulator tonight in my 87 Spider and tested it before replacing the air filter cover. The car started right up and ran smoothly. I measured 13.7 volts coming out of the alternator. Once I replaced the air filter cover and tightened up the air intake, the car would not start. The engine turns over fine, but it won't run and it sounds like it isn't getting fuel. I tried pressing the accelerator while cranking and the engine will run very rough as long as I give it gas.

I found a loose wire coming off a large silver canister-shaped fuse near the air filter cover. I covered the loose end of the tan wire with a gray wire nut in the picture. Could this be the problem? I can't find where it should connect. I couldn't find any other wires that I might have knocked loose.

Please offer troubleshooting tips. This is my daily driver.
 

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But Mad North-Northwest
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Holy crap, son, but that is one seriously messed up set of wiring!

The most obvious culprits are either you introduced an air leak in the AFM hose, or the AFM wiring got messed up when you disconnected & reconnected it. But with all those extra wires and splices and crap it might be tough to find the issue if it's electrical...
 

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Discussion Starter #3
Tom, you are a genius. I checked the AFM wiring connector and sure enough one the wires pulled right out of the connector. I reseated it and all is fine now. I will do a proper fix this weekend. Thanks very much for your prompt reply.

I know the wiring is a mess. I had an alarm installed when I was younger and didn't know any better, and the installer spliced wires all over the engine compartment and interior. I'm trying to use papajam's wiring diagrams to trace through and remove the remnants of the alarm system, but I get confused when I encounter relays and fuses that aren't on the diagrams.
 

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Get rid of the wire nuts and replace them with soldered or crimped connectors.
 

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Trained (ex)Professional, , 1953-2018 RIP,
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I'm trying to use papajam's wiring diagrams to trace through and remove the remnants of the alarm system, but I get confused when I encounter relays and fuses that aren't on the diagrams.
There's a pretty good chance that if you run across a device that isn't on the wiring diagrams, that it wasn't fitted by the factory. An example is the 'silver can' (looks like a turn signal flasher to me) and the Bosch relay right next to it. Perhaps used to pulse the horns when the alarm was activated?
The two black in-line fuse holders seem a bit fishy as well. A/C equipped cars have one fuse holder in this location but it's wire runs along the firewall to one of the two cooling fan relays on the right inner fender. And I don't recall a 2nd fuse holder in this location but could be mistaken.
 

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Discussion Starter #8
There's a pretty good chance that if you run across a device that isn't on the wiring diagrams, that it wasn't fitted by the factory. An example is the 'silver can' (looks like a turn signal flasher to me) and the Bosch relay right next to it. Perhaps used to pulse the horns when the alarm was activated?
Thanks papajam. It seems all of the alarm components were spliced into a cluster of 4 wires (red, tan, orange, yellow) that I traced back to a hole in the firewall for the A/C hose. Do you know if these wires correspond to any subsystem on the wiring diagrams?

The two black in-line fuse holders seem a bit fishy as well. A/C equipped cars have one fuse holder in this location but it's wire runs along the firewall to one of the two cooling fan relays on the right inner fender. And I don't recall a 2nd fuse holder in this location but could be mistaken.
Those black fuse holders are for the headlight wiring upgrade kit. I have a 20 amp in-line fuse for the A/C coming off the junction box which you can't see in the picture. There is also a 7.5 amp in-line fuse in that area that I don't know if it is factory.
 

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Discussion Starter #9
kcabpilot and alfaparticle, thanks for the advice. I will install crimp connectors.
 

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But Mad North-Northwest
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Bah. Crimps are fine. All the original connectors are crimped.

Just get a high quality manual crimper and learn how to use it. Not a cheap one: you want one of the spring loaded ratcheted ones. It's not very hard to do right.
 

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Bah, bah.

Original connectors were crimped using calibrated electro-pneumatic crimping tools before the wiring was installed in the car. There are very few if any crimped butt connections. You will never be able to reproduce that quality of crimp using hand tools. A butane soldering iron is cheaper than a "quality manual crimper" and with just a little practice you end up with a mechanically and electrically superior connection. For lugs I crimp then solder.

It's your car do as you like.
 

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But Mad North-Northwest
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Sure you can match the quality with a manual crimp. My group at work does it all the time in the lab stuff we manufacture. The industry considers crimping an acceptable and permanent connection method.

They use pneumatic stuff when they make cars because it's faster and more repeatable in a production setting. And they don't use any butt crimps because the wiring harness is designed not to have them: there's nothing inherently different in crimping a wire to a terminal from crimping a wire to another wire.

The key is to use the right tool and pay attention. This goes for any connection method.

Never had any issues with the crimps on the car. The connectors themselves are another matter...
 

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We hardly ever solder anything on the aircraft. Everything's crimped. Sure it's danged good crimp but it is crimped.
 

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Alright, I bow to yall's obviously superior experience. I mean I only have 46 years experience as an electronics technician 5 of which I spent as an Instructor Certifier for the Navy's Micro-Miniature electronics repair program along with certifications in several types of crimp-pin assembly (yes there are separate certifications for different types of pins), fiber-optic termination and repair as well as several years of inspecting and certifying shipboard installations to meet SPAWAR standards.

It's your car fix it however you like.
 

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Alright, I bow to yall's obviously superior experience. I mean I only have 46 years experience as an electronics technician 5 of which I spent as an Instructor Certifier for the Navy's Micro-Miniature electronics repair program along with certifications in several types of crimp-pin assembly (yes there are separate certifications for different types of pins), fiber-optic termination and repair as well as several years of inspecting and certifying shipboard installations to meet SPAWAR standards.

It's your car fix it however you like.
what's the secret? so youthful looking! :)

PS: ain't it y'alls?
 

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Discussion Starter #18
Wow, what a lively discussion. After careful consideration of all the expert opinions, I will stick with wire nuts :)

I spent the day removing the alarm system and guess what? No more splices. I must have taken out 100 feet of wiring. My engine compartment is now nice and neat. And I can finally follow the papajam wiring diagrams.
 

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Trained (ex)Professional, , 1953-2018 RIP,
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Please keep in mind that automotive manufacturers use stranded cable for its flexibility. Soldered connections remove all flexibility at the joint and may increase the chance of a work hardened failure.
For electrical work, I use a rosin core solder. Acid core and coreless solders with flux pastes are reserved for pipe sweating, radiators, etc.
 
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