Tach signal for data logger

[pokeyl]

I did a search and could not find an answer. Were do I connect to pull a Tach signal for my data logger, other than the ODB II connection.

[SouthArk370Z]

Originally Posted by pokeyl

I did a search and could not find an answer. Were do I connect to pull a Tach signal for my data logger, other than the ODB II connection.

FWIW, the ECM determines RPM from the POS (crankshaft position sensor) and then sends the data to the tach via CAN (ref pg MWI-12 of 2009 FSM).

What kind of signal is your datalogger looking for? 0-5V? Pulse? 4-20mA? If it's looking for a pulse, you may be able to use an inductive pickup on one of the spark plugs or tie into one of the coil primary leads.

[pokeyl]

Zt-2 Wideband Air/Fuel Ratio Meter and Datalogging System : Model 2010

RPM input, tach, low side ignition coil, crank, cam sensor.
0-5V, 0-12V, square wave, 0 -18000 RPM

[SouthArk370Z]

Originally Posted by pokeyl

Zt-2 Wideband Air/Fuel Ratio Meter and Datalogging System : Model 2010

RPM input, tach, low side ignition coil, crank, cam sensor.
0-5V, 0-12V, square wave, 0 -18000 RPM

"Low side ignition coil" (primary side of coil) will probably be your best option. You can also tap into the crank or cam sensor, but that may load the circuit.

See the FSM (link in my sig) for wiring diagrams, wire colors, and physical locations. The EC (Engine Control system) section will be a good place to start. If you use Adobe Reader, the Advanced Search will allow you to search all sections of the FSM at once.

Edit: You may have to set the proper range on the datalogger. Signal levels for the sensors will be in the FSM.