For sensitive circuits like TPS or AFM wiring. I'm not convinced that butt splices will transmit cleanly, but I'm worried that solder will crack.

I'm considering solder, then finding some kind of splice case or something to protect the splices from vibration, but I don't know if that's the way to go either.

What say ye, Yotatech?

 

Either really good quality butt connectors or solder them and use heat shrink tubing to protect it.

 

I repair welders and plasma cutters for a living and let me tell you, those machines see just as much abuse/vibration as any vehicle would.

We just solder and heat shrink the connections. That's what I'd do.

 

Why would you feel your solder joints would crack??

If you use the correct solder I have never had any break over the years .

a few trailer plug installs other than the woman forgetting to unplug the light cord quite a few times .

No solder failures.

There are so many different grades of heat shrink tubing I sure you can find one that works for you that you like.

 

Great input, thanks guys!

Heat and vibration? My soldering experience is limited to plumbing, so I'm just trying to cover all my bases. If you guys think some decent solder and quality heat shrink is all I need, I'm good with that.

 

The solder should hold up great if you do it right. If your worried about the solder cracking then some decent butt connectors crimped tightly and correctly would work just fine. Whether you go with soldering or the butt connectors, make sure you route the wires where they won't be pulled easily. Zip tie and put some conduit over it and you'll be set.

 

I've worked in the Electrical utility industry in different trades for over 36 years and I've spliced cable from 12Vdc. to 69,000 Vac. and I can tell you that a soldered connection is by far a better means of connecting wires than a crimped connection any day. When connecting any wires you have to guard against moisture entering the connection. If you get moisture ingress you get corrosion and ultimately deterioration of the connection.
I've built and repaired a lot of wiring harnesses over the years and my method of splicing wires may be considered overkill by some, but I've never had a splice fail. I live on the East coast of Canada where there is lots of salt and lots of moisture.
First and foremost the wires you are putting together have to be clean and shiny (No oxidation), if you don't get the oxidation removed, then you are wasting your time trying to make a splice, second your soldering iron or gun needs to be able to put out enough heat to thoroughly heat up the connection so that the solder will flow between the individual strands of the wire. If this doesn't happen then you will get a cold solder joint.
Here's what I do; I take an insulated butt splice that is meant to be crimped and cut the insulation off of it so that I have the bare link. I use the link as the connector, prepare the wires and insert them into the link and solder them. The end result is a smooth connection no stray strands that might come out of the heat shrink later and cause a short. To finish it off I put two layers of heat shrink over it. The first layer covers the link and about 1/4" of insulation each side of the link, the next layer goes a 1/4" beyond each side of the first layer.
If the splice will be in a wet area I'll use the type of heat shrink that has the glue in it to seal out moisture, if you can't get this type of heat shrink locally, you can do the same thing by covering your splice with glue from a hot glue gun and then install your heat shrink over the glue.

 

Awesome, Hadmatt. A friend suggested doing the connector/solder thing like you said, except he uses electrical paste instead of glue inside the heatshrink. Any thoughts on that?

 

i would think that if u use the right size shrink wrap and over lap about half inch and then wrap it all in electrical tape when done it shouldn't rust or get moisture in them, unless u sink it in a lake for long times. but if u really want to use something in there i would use the glue, or a silicone based item.


oh and i just got done fixing some wiring in my engine bay and i just ran it long and then taped it all up...

 

The glue inside the shrink tube or the glue from a hot glue gun will harden once it cools, thus eliminating any chance of moisture getting into a connection. I doubt that the paste would give you the same result.

After the splicing is done, I wrap my wiring harness in two layers of electrical tape, more for protection than insulation. Good quality electrical tape is good for 600vac per layer.

 

I thought I invented that method of making electrical connections.

 

Unless you are older than I am...I'll claim the patent rights!