Ok the other day i asked if anyone knew how to do this to save me from buying one but got no response so did a bit of recon and worked it out for myself!
Whilst doing it i thought i'd create this quick guide to show peeps how to do it yourself. BTW thought i'd make it as basic as possible so apologies for the first few obvious steps
NOTE: i did this on my VTS engine that uses BBC2.2 Coil Ignition packs, those of you with VTR's, 1.4 and 1.1 should be able to do the same with your coil packs! However they are slightly different - also i'm sure some of you are aware these ignition systems work on wasted spark technology thus one coil pack per 2 cylinders
Anyway first things first what you need:
As shown above, Rachet, Extension Bar, Size 4 & 5 Hexagon key and Multimeter, optical - Haynes
Step 1:
Remove the coil pack cover: size 5 hex key, six bolts!
Step 2:
Remove the coil pack: size 4 hex key, 5 bolts!
Step 3:
Disconnect the coil pack and remove from spark plugs as shown:
Step 4:
Testing: the coil pack has four pins as shown:
From left to right:
Pin 1 = Primary trigger for coil pack 2 - this serves spark plugs 2 and 3
Pin 2 = 12v battery suppy voltage via fuel injection relay
Pin 3 = Chassis earth
Pin 4 = Primary Trigger for coil pack 1 - this serves spark plugs 1 and 4
In case your wondering how to determine which is which in the above pic i just unplugged the coil pack and turned it upside down
Step 5:- Primary Circuit Test
The first test looks at the primary circuits. Using multimeter set it to 200 Ohms and plug the leads into the correct ports. Now to test primary circuit one - this serves spark plugs 1 and 4, place the positive lead on pin 4 and the negative on pin 3 as shown:
you'll get a reading like this:
do the same for primary circuit 2 bridging pins 1 (positive lead) and 3 (negative lead) and you'll get your reading here's mine:
According to the Haynes manual the primary circuit should be between 0.6 and 0.8 Ohms from mine it tells me my first coil pack is on its way out
but pack 2 is fine! - typical
Step 6: Seconday Circuit Test
The secondary circuit test looks at the resistance in the secondary windings responsible for providing your high voltage spark to the spark plugs. To test these set the multimeter to Ohms 20K.
This is simple to determine, you already know coil pack 1 serves spark plugs 1 and 4 and coil pack 2 serve the others so using the multimeter bridge between spark plug connector 1 and 4 to determine the first secondary windings resistance as shown:
It doesn't matter which way you put the positive and negative leads for this i chose positive on spark plug 1 connector.
Repeat the same for spark the secondary coil as shown:
Onces again referring back to trusty Haynes the secondary windings should read 19 Kilo-Ohms both of mine were producing around 15 kilo-Ohms showing signs of needing replacing
That's it SIMPLE! So rather than waste £100 on a part you might not need to solve your problem test it first! Unfortunately for me i now have spend sometime serving the net to find a good replacement on the cheap!
Hope this guide helps!!
VTS Coil Ignition Pack Testing
Linear Mode
