Eratic Tachometer AQ205A

[Ali cat]

I am getting some eratic readings on my tacho, they are showing an increased reading.I have cleaned all the terminals/conections and no breaks in the wires.Could this be an alternator problem as I have a small wire that connects to the alternation and it looks like it has a small resistor near the connection.Any other advise

 

[Don S]

Re: Eratic Tachometer AQ205A

The alternator has nothing to do with the tach. The tach gets it's signal from the - terminal of the coil.

Make sure the coil tower isn't cracked and arching to the small terminals.

 

[wkb2460]

Re: Eratic Tachometer AQ205A

I read somewhere that on the back of your tach is an adjustment for 4, 6 and 8 cylinder engines.
Try moving the knob between all ranges then set it back to your engine, it just might clear the problem.

 

[larson260]

Re: Eratic Tachometer AQ205A

Had the same problem on my 2006 Larson.
If you can't get it straightened out and the gague is manufactured by "Faria", go to there website and you can send it to them for diagnostic service. Faria has a so called life time guarantee and will replace it in six weeks for $50.00.

 

[Ali cat]

Re: Eratic Tachometer AQ205A

Thanks for the reply, I checked in the dark,no jumping sparks found.This is a new coil,for"without a resistor" is this correct? I replaced because I thought the old coil was faulty.I had a mate fit new connector to the wire and have the following.Negitive,1xblack to distributor &1x grey to harness.Possitive 1xpurple to choke,1xpurple to harness & 1x Dk blue/purple to distributor can you confirm this is correct please?

 

[Ali cat]

Re: Eratic Tachometer AQ205A

Thanks I tried turning the small plastic screw that I believe is the "pulse screw" back and forth and still no change.