Cut knock sensor wire.

[Maverick87]

Need advice on how to repair the broken wire? If I crimp the wire and heat shrink it will it be fine or cause me problems?

 

[Turbo6inKY]

It'll be fine. Knock sensor doesn't operate on impedance.

 

[Mike T]

Crimp connection could out last us all........my luck isn't that good though so I would solder and heat shrink it.

 

[michael evans]

A wire that important, I would not put a crimp on it as a permanent repair. I would solder a joint then shink wrap it.

 

[kjizzle]

All of you saying "solder", just about every manufacturer recommends a butt connector instead of solder. Solder is actually worse in a hot, high vibration environment. Even the official Audi/VW wire repair kit (which is used on everything from Golfs to R8s) is all butt connectors. Solder actually isn;t the best choice for most automotive wiring.

 

[earlbrown]

I wonder if the OEMs recommend butt connectors because they are almost idiot proof? I'm often amazed at the large number of professional techs that know nothing about wiring (and damn sure can't run a soldering iron). It's baffling.


For that knock sensor wire repair, I would solder and shrink it and not even consider using a butt splice (and I have a box of the nice ones with the built in heat shrink left over from my car stereo days).


Now hooking a wire to a metal end, a splice is preferred to allow some flex at the termination point and not cause a stress riser. In that case, I usually solder LIGHTLY on the end away from the wire, but not a full solder connection. That way I get the solid electrical connection but not cause a future issue down the road. Best of both worlds.

 

[scgnx2]

All of you saying "solder", just about every manufacturer recommends a butt connector instead of solder. Solder is actually worse in a hot, high vibration environment. Even the official Audi/VW wire repair kit (which is used on everything from Golfs to R8s) is all butt connectors. Solder actually isn;t the best choice for most automotive wiring.

OEM’s use crimp type connections because there fast and pretty reliable. However, a properly soldered wire connection with shrink tubing is extremely reliable. I say this because I spent many many years as an Engineer developing crimp connections and electrical connectors. I have seen OEM customers actually apply solder after crimping the connections. This is done for maximum reliability.

 

[captndave737]

The biggest problem with soldering is it has to be done right. That means clean wires. 30 year old wires can be corroded pretty far in. I use lots of flux without solder until the copper is nice and shiny and then add solder. The splice needs to be hot enough for the solder to flow and get wicked into the wire. The solder should be shiny when it's done and cooled. If it's dull you have a cold solder joint and high resistance. Take it apart and start over.

When it's done correctly nothing can beat it. I've been redoing a lot of splices in the wiring harness while my engine is out. I found some heat shrink with sealant in it that melts and seals the splice completely after I've soldered them.

 

[Mike T]

There is a connector with solder, heat shrink and sealer all in one. You position it like a crimp but use a micro torch or lighter to melt solder, heat shrink and seal simultaneously.

Varying quality of these too ( heat shrink will burn before solder melts), best ones I've every used were by a company that unfortunately is out of business now.

 

[No disintegrations]

There is a connector with solder, heat shrink and sealer all in one. You position it like a crimp but use a micro torch or lighter to melt solder, heat shrink and seal simultaneously.

Varying quality of these too ( heat shrink will burn before solder melts), best ones I've every used were by a company that unfortunately is out of business now.

I like the ones from Tyco

 

[robertf]

You can crimp, then run a bit of solder and finally heatshrink.

 

[Chuck Leeper]

just about every manufacturer recommends a butt connector instead of solder.

We frequently get the "crimp joint" harnesses coming into the shop.. Usually, because they failed.
A butt can leave some wire strands loose. A properly done solder joint, not so much.