speed sensors used for EJ conversions?

steptoe · Post by **steptoe** » Sun Jul 01, 2007 6:46 pm

In my slow learning curve of what is needed to 'shove an EJ in' an MY or L, the speed sensor has reared its ugly head.

In L series MPFI it is in the speedo part of the instrument cluster so I guess it is used in these models. MY speedo heads do not have a speed sensor in them, so this might explain why some have fitted Impreza instrument pods in MY dash, including Daniel fitting SVX gauges in his EG33 Brumby. Noted that someone has suggested a cruise control magnet and coil on a drive/tailshaft. I have found that http://www.tcag.com.au (who make the AP series cruise controls)have a bit that fits in between gearbox and speedo cable for most cars? that produces a signal.

What have all you EJ converters done out there for this ?

Is the signal supposed to be any sort/ produce a certain number of signals ?

stamp_licker · Post by **stamp_licker** » Sun Jul 01, 2007 8:14 pm

I used the dash one in the L for mine, it also controls the ej auto fine .

Chris_Rogers · Post by **Chris_Rogers** » Sun Jul 01, 2007 9:14 pm

OE one is the dash is what I am using.

MY_STI · Post by **MY_STI** » Sun Jul 01, 2007 10:15 pm

Afaik the speed sensor is used for leaning off a little extra during light cruising and engine braking (and speed cut for JDM ecu's).

So expect slightly better highway economy and less/no backfiring when decelerating with it hooked up.

Recall reading somewhere that the input for early libs is 4 pulses per rotation of the speedo output/cable. Waveform would be a basic squarewave, which would be fairly 'dirty' if a magnet/reedswitch was used. But I don't think it would matter a great deal, the ecu would most likely 'debounce' the signal, and would be triggered off the rising or falling edge of the pulse.

Using the factory speed sensor in the L turbo cluster in my L conversion, seems to be working fine. Haven't yet checked the accuracy but its not throwing an error code, which is a start.

Not using one at all in the MY conversion. 'Pops n crackles' lots on decel.
Still gets less than 10l/100km on the highway, despite the incredibly unaerodynamic configuration and my driving.

subarursliberty · Post by **subarursliberty** » Sun Jul 01, 2007 11:02 pm

What about something from here?

http://www.dakotadigital.com/index.cfm/ ... prd109.htm

stamp_licker · Post by **stamp_licker** » Mon Jul 02, 2007 8:09 pm

yeah the wave shape is different from lib to l.had a oscilloscope on the ej one on the box and then on the L dash one it looked different but still managed to do the same job.I don't understand the wave stuff was just observing what mine was doing.

steptoe · Post by **steptoe** » Mon Jul 02, 2007 10:10 pm

I don't understand just what a speed sensor is meant to do, just yet.

Chris, nice to see you back

Chris_Rogers · Post by **Chris_Rogers** » Mon Jul 02, 2007 10:15 pm

keep reading. it tells the computer how fast you are going.

(been busy as always.)

SuBaRiNo · Post by **SuBaRiNo** » Tue Jul 03, 2007 2:32 pm

I have hooked my speed sensor wire to my aftermarket cruise control reed switch on my MY conversion. Didn't seam to make any differenece but it no longer spits the speed sensor code.

Dave

Bratgeebah · Post by **Bratgeebah** » Thu Jul 05, 2007 5:55 am

I'm looking at getting one from the speedo shop in Ringwood, Melbourne. They told me they can get it in the ball park for pulses/kilometre. They will 'splice' it into my speedo cable. Unfortunately I think it's around $240 fitted to cable. It also needs a stright bit of cable to be fitted so in an MY I'll need to make the cable longer, which could cause the speedo needle to 'whip'. Has anyone else used something like this?
Gee

steptoe · Post by **steptoe** » Thu Jul 05, 2007 9:31 am

SuBaRiNo s idea must do something and the change to the number of magnets changes the number of pulses. The TCAG guys may know how many pulses one two or three magnets will read out and you may be able to buy spares' like the coil pick up and magnets and bands to hold in place.