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Discussion Starter #1
The ignition coil takes a small voltage in (The 'LT' or Low Tension voltage) and transmits a big voltage out ('HT' or High Tension). The output goes from the coil to the 'King Lead' which is the main HT lead

that goes to each distributor. This is then passed to the relevant HT lead and spark plug via the rotor arm which spins inside the distributor.

Coils are pretty robust on thse cars but if you find you have a switching voltage on the LT side and no spark occurring, this is the likely culprit. OEM parts are expensive but this is another Bosch part

(0221118307) and you can pick up a much cheaper aftermarket version from your local autofactors. I paid £32 for two coils (but that was discounted so expect to pay around £40-£50).

Changing the coils is an easy job and only takes about 30 minutes to an hour for a novice.


DISCONNECT THE BATTERY WHEN DOING THIS!
 

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Step 1 - The coils are located on the offside (drivers side) next to the firewall (right at the back of the engine). Start by removing the main HT lead, this simply pulls off but the rubber can bite so wriggle it

free if needed. If you're not sure then mark up which lead went on which coil but it should be obvious by their position really.



Step 2 - Now remove the plastic cover which clips around the coil, a small flatblade screwdriver will help you ease it out and pry it off (gently, don't snap it!). Note you won't be able to take it clear until

you've disconnected the wiring in step 3/4 as it feeds through the plastic cover



Step 3 - You can now see the LT wiring which has a positive and a negative. Note the wiring colours and be sure to put them back the same way!! There are two coils, one takes the input signals and passes

them onto the next so you have:

- Coil #1, nearest the wing, this has a brown negative feed and a black wire to link to the second coil. It has a red positive feed and a pink wire to link to the next coil
- Coil #2, this has the black and pink link wires from the first coil as negative and positive respectively




Step 4 - Remove the 8mm and 10mm nut holding the wires in place and pop the wires to one side (repeat this on both coils)

 

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Step 5 - you will need a couple of 13mm spanners to undo the nut/bolt holding the two coils in place next. This is a little fiddly but not too difficult with a long spanner, remove the nuts, bolts and washers




Step 6 - Pull the coils clear of the car and you can retrieve all the nuts and bolts that have been dropped down beneath them over the years!!



Step 7 - Your fresh new coils may, like mine, come with two 10mm terminals rather than one 8mm and one 10mm so you may need to grab some matching nuts if they don't come with the coils



Step 8 - If you did remove the plastic covers once you disconnected the wiring (you don't have to) then refit now

 

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Step 9 - Pop your bolt and washer in one side then hook a coil on as shown. Loosely fit the other washer and bolt and then hook the second coil in and tighten it up. Don't tighten up one side until you have

fitted both loosely. Again, this is a little fiddly but not too, just take your time.



Step 10 - Refit the wiring as described in step 3



Step 11 - Pop your caps back down and you have finished

 
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