Lesson learned (Ignition Coil Purchase)

[XC70Rider]

I replaced the original coils at 174k miles in July 2022 with Bosch coils I got at FCPEURO for $273 total. No misfiring just wanted to replace those aging 16 year old coils. I replaced the Volvo spark plugs with a free trade in with FCPEURO. I crimped on a used harness I got from Erie Volvo for $130. Also rebuilt and cleaned the original fuel injectors. She runs nice and smooth for a P2 approaching 185k miles.

Next job will be replacing those original injectors and fuel pump within the next year with the Bosch brand.

[abscate]

My regular 250 mile loop averaging around 65mph (some 55, some 65 limits) went from 28mpg to 31mpg. Been a while since I’ve seen it break 30 so that is a win.

Getting three bucks+ back on each loop. So 10 loops is almost a new coil. Karma for less pollutants and CO2 also applies

[cn90]

When it comes to sensors, coils, MAF...

I have learned over the yrs from Honda, Toyota, BMW, Volvo etc., it is always a good idea to use the
Genuine parts or if you know "for sure" who makes it, then use that brand.

Using other brands is not the end of the world, but it can cause misfire, and worse, can strand you.

I always carry a basic OBD-Ii scanner and some basic tools and a few spare coils (from junk yard) in the trunk.

In the BMW world, Bosch and Bremi makes ign coils.
In the Volvo world, it is Bosch (it was Denso for a while).

[cn90]

Also...aftermarket is good for unimportant jobs such as light bulbs, antifreeze, engine oil, tires...just do your research and use it.

Important stuff (either from labor charge or risk of stranding) such as engine valve seals, RMS, ign coils,
use Volvo, Bosch coils or Corteco seals or risk doing it again...or stranded...

[Krons]

Important stuff (either from labor charge or risk of stranding) such as engine valve seals, RMS, ign coils,
use Volvo, Bosch coils or Corteco seals or risk doing it again...or stranded...

The ease of replacement (and two spares in the trunk) was my logic to go with my $55 set of coils. Previous set of these in my kids 02 S60 have lasted 30k miles so far. For sure some risk but $55 vs $185 with easy replacement? The bet is in play…the house may win but worth a shot.

[cn90]

For got to mention, I use junk yard Genuine coils...$10/each.
Or new Bosch (Bosch 30713416) is $45/each.

[erikv11]

Junkyard coils are fine when you have a failed one(s) to replace. But for the routine maintenance purposes being discussed here they would make zero sense.

[cn90]

I'd like to see a few sets of data...of before and after.
Before: functioning factory coils.
After: brand new factory coils.
Cars driving under identical condition, tires properly inflated, same gasoline, same distance.

Then I might believe it.

Elective replacement of coils makes no sense unless definitely proven that it helps.

For me, coils are similar to light bulbs, I only replace light bulbs when they are burned.

I may be wrong re old coil vs poor mileage...but I have not seen any factory manual (Honda, Toyota, BMW, Volvo etc) recommends elective replacement of coils.

[Krons]

I'd like to see a few sets of data...of before and after.
Before: functioning factory coils.
After: brand new factory coils.
Cars driving under identical condition, tires properly inflated, same gasoline, same distance.

Then I might believe it.

Elective replacement of coils makes no sense unless definitely proven that it helps.

For me, coils are similar to light bulbs, I only replace light bulbs when they are burned.

I may be wrong re old coil vs poor mileage...but I have not seen any factory manual (Honda, Toyota, BMW, Volvo etc) recommends elective replacement of coils.

I’ll have more data in the upcoming months. I have consistent loop with same fuel every time.

My interest in changing was seeing Erik’s results and having a ~10% drop in mpgs plus seeing a trace of fuel in my oil sample test when the car is run 90% 4-lane highway.

I suspect a little extra fire is burning just a little more fuel to improve the efficiency. Not sure used coils are worth it unless the donor has very low miles.

Remember, Volvo says believes in lifetime transmission fluid…

[cn90]

I understand Bosch is the factory supplier of Volvo coils.
Has anyone here used the Bosch coils from eBay sellers?
As you know, NOT all eBay sellers are shady, some sellers sell genuine Bosch stuff...In the attached photo,
it shows coils made in Slovania.

For comparison purposes:

- eBay seller: set of 5 Bosch ---> $160 for 5 or $32/each.

- FCPEuro, Autohausaz: ---> $240 for 5 or $48/each.

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