Tacho (yes i know there is an ultimate thread)

[WhiteLightning]

Before i say anything id like to make it clear that i am fully aware of the prescence of the ultimate tacho thread...and no it hasnt helped me in my quest to get a working tacho in my car...

Right...i have a VP and i have a tacho (el cheap n nasty from autobarn)...it is not like any monster tacho with shift light...more fitted to a speedboat...but n e way...cant get it to work..

is there sumthing im not getting in relation to the wire near the strut tower. it has a voltage, between 1.5 and 3 DC and 3 ish AC...the tach states clearly will work on all ignition systems...and says to connect to a negative of a coil...

maybe if i go get another better brand one...if so what brand and where??

Thanks, Ben

[Tasmaniak]

it sounds like you have the wrong wire. The tach wire sends a 12V pulse everytime the coil (coilpack) fires a spark plug. This wire is best tested for by using an LED test light. It will look like it's flickering when you have the wire but then as engine speed increases it will almost become solid because of the rate it's flashing at.

Then again, if you are using digital multimeter it may not be able to read the wire properly because the moment it's starts read a higher voltage then line returns to 0V.

So in short, you may or may not have the correct wire. I doubt it is the tacho. Although it is cheap they at least still work LOL

[WhiteLightning]

it sounds like you have the wrong wire. The tach wire sends a 12V pulse everytime the coil (coilpack) fires a spark plug. This wire is best tested for by using an LED test light. It will look like it's flickering when you have the wire but then as engine speed increases it will almost become solid because of the rate it's flashing at.

Then again, if you are using digital multimeter it may not be able to read the wire properly because the moment it's starts read a higher voltage then line returns to 0V.

So in short, you may or may not have the correct wire. I doubt it is the tacho. Although it is cheap they at least still work LOL

yeah...quick question...would just anormal bulb test lite have the same effect as the LED one...and yeah i see ur point on the digi multimeter thing...it only really reads sine waves...not a true rms meter...so i will purchase a test lamp today and see how i go

[Tasmaniak]

no, a standard bulb test light MAY show it. By simply getting brighter as the revs increase.

[WhiteLightning]

no, a standard bulb test light MAY show it. By simply getting brighter as the revs increase.

yeah...i bught one just now...right before reading ur post...but see i have the right wire...(cant go wrong...brown wire...white clip...near strut tower...) its just im not getting the desired effect...i would pop the bonnet and test it all again but i need a helping hand to open it...so it will wait til this afternoon...see the instructions say negative of the coil...is this brown wire a negative of the coil...and if not where can i find one...others say alternator wires somewhere...otherwise i pull the cluster out and look there...but i daresay they are the same wire (brown-red/brown)...so now im unsure of whats to do