[s-cars] 1.8t Coil Pack Conversion Shopping List

[Dave Forgie]

Some of you might remember that I've been developing this conversion in
my head for a number of years because I always thought that,
eventually, our OEM coils would no longer be made and I wanted a back-up
plan for my car. In the last four or  five months, I noticed that I was
getting some missing/bucking under WOT, and high boost, at high speed.
I  figured coil (or POS) but I didn't want to spend the money on
replacing old (but perhaps robust) technology  when newer technology is
out there.

 I know all about the 1.8t coil pack recall on some of the Bremi-made
coil packs but I think that VW/Audi is  through all that now. For
whatever reason (excess supply, the need to do some good PR), these coil
packs  are now very reasonably priced. Since I had the need and the
price was right (about $200 - $250 for the parts  versus the OEM
equivalent of about $925 for five coils and two OEM POS units), I
decided to make the
 conversion. As you may have seen from my posts, it seems to be working
absolutely fine - so far. (YMMV).  Just like new OEM parts should. Hey,
they are OEM - just from a newer technology!!

 If you are interested in making this conversion, you need the parts
listed below. They are mostly dealer parts.  I got mine through Kris at
VM Autohaus (604-298-9637) who said he would be interested in putting
"kits"  together with all the parts (except items 7 and 8 that you need
to scrounge). For Canadians, using Kris is a good idea. For those in the
States, there is still a bit of a gap between the US dollar and
Canadian dollars that should still make it an okay deal. However, I know
ECS tuning has the coil packs for
 about the equivalent price (in absolute dollars)that I bought mine for.

 Anyway, here is the shopping list:

 1. 5 units of 06B 905 115L late model 1.8t coil packs (which are POS,
coil and plug connectors all in one)  should be about $25 each. Note the
"L" is very important. DO NOT ACCEPT ANYTHING ELSE - unless they  are
known to be better.

 2. 5 units of 4B0 973 724 empty four wire connectors (to mate to the
115Ls) (about $10 each) (Seems  expensive but they are worth it)

 3. 10 pieces of 000 979 133 A - two female spade connector pig-tails
(NOTE: If I
 had this to do over again, I would search out the equivalent empty pins
and crimp/solder continous pieces of  wire rather than spicing these
into the system.) (About $4 each piece). These pins go into the rear of
the 4B0  973 724 four pin connectors.

 4. 25 pieces of 357 972 741 A - wire sealing grommets (red) for the 4B0
973 724
 connectors and 000 979 133 A wires (about $0.30 each). They seal the
wires into the 4B0 973 724  connectors. Install BEFORE you connect the
wires to anything else.

 5. 5 pieces 6X0 971 921 A - two-part plastic boots for the 4B0 973 724
connectors. (about $3 each). At first I  thought they were cheesy but
they are actually quite slick. They are designed to retain 1/4"
corrugated split plastic wire loom which helps to corral those wires.

 6. 3 pieces of 000 979 134 - two male spade connector pig-tails (again,
I would search out a source of  empty male pins and forget slicing these
in)

 7. Two, four-pin male spade connectors to fit into the four pin female
spade connectors that carry the signal  from the ECU (and a ground) and
normally fit into the four pin end of the POS units (N122 and N127).
You  can search for somehting better but I found that there is a four
pin, left tail light, connector PN 191 972 704  from a the mid-90's
Jetta IIIs (might also be in some Audis because the plug has both VW and
OOOO
 molded into it). These connectors are female "pin" power plugs but they
have the exactly correct pin spacing  for the the OEM POS input
connectors. They need to be modified (a lot). But this is pretty easy.

 I bought two of these taillight plugs with the four wires and
connectors (each). By
 removing the female pins (from the connector side with two bent paper
clips to push the retaining pins in),  you can salvage eight pins for
use in the other connector projects (if you want to save a few $). Once
the  female pins are out,
 you need to trim off 4 mm on the nose of the connector and then remove
 all the protruding bits. I used an X-acto saw (that I have had for 40
 years when I used to make models as a kid). Don't trim much more than 4

 mm or when you load the male pins, 000 979 134 (come 2 to wire, you
need
 5 so three wires), they will push right through (don't ask how I know
 this). I think it works out that if you cut right through the center of
each O in the OOOO symbol, the amount  removed is just right. You load
the 000 979 134 pins from the back.

 Once the pins are in, you can see how the newly re-gendered
(gender-reassigned) connector fits into the POS connector. Spacing is
correct but there is a lot of exposed, non-waterprood, non-connected,
plastic to deal with. I am planning on zap strap(s) and
 some silicone to solve this problem.

 8. 2, three pin (male) power connectors to receive switched power going
to the
 primary side of the coils. These connectors are on the connector rack
on the fire wall and are the two beside  the 02 connector. You need to
replace them because when you remove the OEM coil pack, you disconnect
and remove these connectors. I cruised a wrecking yard and found that
the solution is the end of a dead  three wire VW O2 sensor (e.g. 90 to
92 Jetta II). You need two. The male pin connector even has the grove to

 slip into the firewall bracket and fits the power connector perfectly.
I crimped on purple power wires that will  be connected to Pin No. 1 on
each of the five coil pack connectors.

 9. Labling tape (1/2" masking tape) so you can keep all the wires
organized as to where they are going or  coming from.

 10. Colour-coded wire, butt connectors and good crimpers, and/or
soldering iron, solder and heat shrink  tubing, 1/4", 3/8" and 1/2"
plastic wire loom, zap straps, etc.

 11. Instructions and/or the S4 and 1.8t wiring diagrams (I will post
the instructions
 shortly)

 The adventure begins. I expect that you will post
improvements/alternatives to my solutions for items 7 and 8.

 Dave F.