03-01-2014, 05:27 PM
Don't worry about the spare wire/pin on the tacho - it'll be fine just leaving it there.
The above method will work fine and have successfully done similar myself when I fitted an Emerald K3 to a friends 205. It's a much better method than using a tacho converter which are, in my opinion at least, a bit of a bodge.
Effectively all you're doing with the above is bypassing the aggressive filtering circuit that is needed when driving the tacho from a coil (like on the original 8v engine setup). The signal from the Emerald and most later ECU's (GTi-6 etc) is a nice clean 12v square wave and needs far less filtering.
Wire the tacho out (pin 12 IIRC) on the Emerald ECU to wire 112 on the 205 loom and it'll work fine with the above mod - as a bonus, it means Emerald's max rpm tale-tale feature will work.
The above method will work fine and have successfully done similar myself when I fitted an Emerald K3 to a friends 205. It's a much better method than using a tacho converter which are, in my opinion at least, a bit of a bodge.
Effectively all you're doing with the above is bypassing the aggressive filtering circuit that is needed when driving the tacho from a coil (like on the original 8v engine setup). The signal from the Emerald and most later ECU's (GTi-6 etc) is a nice clean 12v square wave and needs far less filtering.
Wire the tacho out (pin 12 IIRC) on the Emerald ECU to wire 112 on the 205 loom and it'll work fine with the above mod - as a bonus, it means Emerald's max rpm tale-tale feature will work.
1990 Peugeot 205 GTi 1.9 // 1991 Peugeot 205 GTi 1.9 16v // 1992 Peugeot 205 GTi 1.9 // 1999 Peugeot 306 HDi Estate