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2014 ATS 2.0T AWD
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Discussion Starter #1
Not a great day.

Tried to fire up my '14 2.0T yesterday and got a rough idle and flashing CEL. Scanned it and got a P0302 code, meaning misfiring cylinder. I thought it was either a bad coil or the dreaded piston issue.

I went out today to try to test the coils and plugs, and found this waiting for me:

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Post shop vac, I discover this:

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So this runs right into the wiring harness. I'd rather not replace the whole thing if I can avoid it. Can this be repaired? Can I do it myself or have the dealer deal with it?
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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Can you find enough slack to cut, strip, solder, insulate the chewed wires? If not, splice in two 3" sections of wire, solder, insulate. Tedious. Lengths of flex wiring bundle tube at any parts store.

That is NOT a repair that should be simply butt-crimped. You NEED the secure electrical/mechanical connection of a solder repair.

Several sheets of clothes dryer fabric softener paper strategically securely placed under the hood and changed once a month will ward off rats, squirrels, and mice.

If a car dealer does the work I hope you have very deep pockets........ labor time is expensive.
 

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2014 ATS 2.0T AWD
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Discussion Starter #3
Can you find enough slack to cut, strip, solder, insulate the chewed wires? If not, splice in two 3" sections of wire, solder, insulate. Tedious. Lengths of flex wiring bundle tube at any parts store.

That is NOT a repair that should be simply butt-crimped. You NEED the secure electrical/mechanical connection of a solder repair.

Several sheets of clothes dryer fabric softener paper strategically securely placed under the hood and changed once a month will ward off rats, squirrels, and mice.

If a car dealer does the work I hope you have very deep pockets........ labor time is expensive.
Thanks. I definitely will take preventative measures to keep the rodents out of there from now on.

I don't think there's enough slack to replace with a single connection, I'll have to splice in some small sections of wire.

I am reading mixed things about solder vs crimping - there seem to be two camps. Some think the vibrations are actually worse on a solder connection rather than a proper crimp. I suppose I'll continue to research.

Thanks for your quick feedback. This is a real pain in the butt.
 

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2013 Luxury ATS 2.0T Manual
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IMO, heat shrink solder sleeves are the way to go. Overlap the stripped sections of wire within the solder ring and then hit it with heat. The shrink tube constricts and glues itself to the wire sheath and the solder melts on the exposed wire section. Tight and waterproof.

 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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Vibrations and solder????? Just what material holds together every circuit board on earth? (and in space)

Solder is the anti-corrosion electrical conductor medium - the mechanical twisting or solder crimp sleeve is the security.
 

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2014 ATS 3.6 Premium RWD, 2016 Corvette Z06, 2018 GMC Sierra Denali 2500HD Diesel
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If you find more damage (often those little gnawing devices hit several areas) then you may find it worthwhile to claim it on comprehensive if you cannot do the repair yourself. If you can do the repair yourself, it isn't expensive.

The mice clearly have been building a nest for some time so take a good look around the engine compartment.

A properly soldered connection stands up very well to vibration and avoids moisture related corrosion that can easily happen with less than perfectly installed crimp connections (and most are less than perfectly installed). Soldering is the best solution for doing this at home (or at a dealership that doesn't want to replace the entire harness which many of them will). High reliability crimps can be made but not with the stuff you find at consumer hardware/big box stores nor with the skill level of a non-pro. A high reliability crimp device forms forms a mechanical "bite" between the wire and the crimp material much like high reliability wire wrap which was used in many critical environments but it requires the right material and more importantly the exact amount of force to create the desired interface without damage to the wire or crimp hardware.

Soldering is dead easy by comparison, clean the connection properly (bright wire, no skin oil or other contaminants) and use a proper rosin core solder and NOT acid core or anything marked for plumbing use. If you clean the wire properly first (alcohol works well) then the rosin core in the solder provides sufficient flux that you don't need to flux the connection separately prior to soldering. The basic rule of soldering is tin the iron, use this to thoroughly heat the connection, and then apply solder to the connection and NOT the iron. A properly heated connection will cause the solder to flow and fill gaps, otherwise you will end up with a mediocre electrical connection and a very poor mechanical connection. The second critical rule is do NOT disturb the connection until the solder sets or you will have a cold solder joint which is no good.

FYI: In the 1950s the Defense department issued a finding that the old practice of making joints mechanically sound (i.e. wrapping a lead multiple times around a terminal) prior to soldering did more harm than good and for most materials the wire or component lead would fail due to mechanical stress before the soldered connection would and that was with solder far inferior to what we use now. Prep the leads by lightly twisting them together and this is primarily to hold them in place while you are soldering and really adds nothing to the realized strength. If you could properly place the bare sections where they simply overlap and lay against each other you would still achieve a strong soldered connection but it is too difficult to do that without a jig to hold them together so a light twist of the overlapping sections takes care of the holding while soldering issue.

Use heat shrink tubing to cover the connection once it is soldered. Realize that your soldered connection is going to have a diameter greater than the single insulated wire so use tubing that prior to shrinking is 2X to 2.5X the diameter of the single insulated wire and keep it well back from the soldering operation so it doesn't start shrinking too soon. Also don't try to push it over the connection too quickly after soldering or the residual heat will shrink it too much before you get it into place. Heat shrink tubing is easily cut so make sure not to leave any sharp solder edges which will cut through it, a quick touch with the hot iron will smooth any sharp points.

The solder joint itself will be rigid and is very vibration resistant (there are many soldered joints used in building the sensors and circuits mounted to the engine) but what you don't want is to create a section where the non-soldered wire has a small distance which has to absorb a lot of flex or vibration. When a repair like this breaks, it typically won't be the solder joint but instead it will fail just to either side of the solder joint where metal fatigue from vibration creates the issue. The heat shrink tubing helps prevent this because otherwise you have an extremely flexible section of bare, no-solder wire just to either side of the connection which is where most of the flexing will occur but properly applied heat shrink helps to reduce the difference in flexibility between the soldered, short bare sections, and regular insulation covered wire.
 

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2004 CTS Lux Sport and 2014 ATS 2.0T AWD Lux
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If you find more damage (often those little gnawing devices hit several areas) then you may find it worthwhile to claim it on comprehensive if you cannot do the repair yourself. If you can do the repair yourself, it isn't expensive.

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Just pay deductible. Unfortunately, I've had to do this 3 times on 2 other cars.
 

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they were under the engine cover??? I found rodent evidence in my airbox [with lots of peanuts so i assume squirrels] but the wiring nearby seemed untouched.
 

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2014 ATS 3.6 Premium RWD, 2016 Corvette Z06, 2018 GMC Sierra Denali 2500HD Diesel
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Mice will also store food for later. When my 1989 Olds Toronado Trofeo was a couple of years old I turned on the defroster one morning as I was pulling out of the garage and heard an ugly rattling noise. I took the pickup to the office that morning and when I came home I found some rodents had transferred about a cup of my German shepherd's dry dog food into the HVAC external air intake. Fortunately that was their first act and they hadn't gotten to any wiring.

I guess the little rats thought they had found a nice new home complete with forced air ventilation.
 

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2013 ATS v6
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Mice will also store food for later. When my 1989 Olds Toronado Trofeo was a couple of years old I turned on the defroster one morning as I was pulling out of the garage and heard an ugly rattling noise. I took the pickup to the office that morning and when I came home I found some rodents had transferred about a cup of my German shepherd's dry dog food into the HVAC external air intake. Fortunately that was their first act and they hadn't gotten to any wiring.

I guess the little rats thought they had found a nice new home complete with forced air ventilation.
Those things can do enough damage to total a car. Repair costs can be higher than it's value.
 

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If the wire is properly prepared, clean clean clean, use the correct solder (rosin core) and the correct solder technique you will have a zero ohms joint that will withstand anything you throw at it.

Also, when soldering 2 adjacent wires you need to space the joints so you don't have a large lump in your wire bundle. I add heat shrink to each joint and the cover the 2 with another layer of heat shrink.
 
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