tricky question that nobody in here knows

[puerkone]

I looked everywhere cant find which unit in a KA24DE engine makes RPMs reading. My RPm cluster does not work any help?

For a KA24DE what unit in the engine sends out RPM signal?

[jetroy240]

I believe the tach is receiving the rpm output signal from ecm & ecm receives the rpm input signal from crank engle sensor (distributor).

[IanS]

I believe the tach is receiving the rpm output signal from ecm & ecm receives the rpm input signal from crank engle sensor (distributor).

Actually the crank angle sensor is used for determining timing advance as well as other ECU functions. The crank angle sensor is usually mounted on the harmonic balancer, or the flywheel, where it car read the rotation of the crank. The distributor is mounted to the exhaust cam, and it reads the rotation of the cams.

The ECU receives its engine speed signal from the Cam angle sensor mounted in the distributor.

[jetroy240]

for 89-93 s13, they don't have crank angle sensor at bellhousing only the S14, that's why they put the crank angle sensor at the distributor w/c also monitors the TDC, engine speed & piston position. It's a matter of terminolgy, but that's their function.

You need a KA24DE cluster for tach to work, if u have the an 89 S13 w/ KA24DE.

Modified by jetroy240 at 9:12 AM 1/19/2009

Modified by jetroy240 at 12:14 PM 1/19/2009
Modified by jetroy240 at 9:36 PM 1/19/2009

[Vegascorbin]

Aftermarket or regular?

Regular, the above is correct.

Aftermarket you could just tap off of the coil for a "tach" signal.

[puerkone]

Kool thanks for the answer I just was confused between those. However for aftermarket, there are 4 wires

red-12 volt ignitionBlack- groundwhite- illuminationgreen- >?????<

[Vegascorbin]

In my experiance the Green wire is your signal wire or the wire you would connect to the coil.

[puerkone]

positive or negative side?

[jetroy240]

Well if you have said earlier that u are installing an aftermarket tach, I could have told that u can tap it to the negative side of the ignition coil, very simple.