speed sensor problem
 

hey guys, i have a problem which i have been suffering with for a long time...
here goes..

i drive a 94 2jzge non turbo i love my car as it is my first car :P got it cheap but there is a minor problem which is majorly getting on my nerves...

As i am driving, the revs will play around a bit.. when i start the car it will be on normal revs or higher (if the engine's cold) but then as i am driving and i stop at the lights for example, the idle will drop down to maybe '500' or even lower.. Sometimes it will even bounce of '0' or sometimes it just hits '0' and stalls altogether (while i am on neutral!!!). Also as i am maintaining a steady speed the CHECK and ENGINE light turn on and stay on for a long time... When this first happened i got scared but then as i have had many mechanics look at it they told me that the warning was harmless and had something to do with the idle problem.....

I AM IN DESPERATE NEED OF HELP AS I HAVE SPENT A LOT OF MONEY TO MECHANICS FOR THEM TO TRACE THE PROBLEM....

i have had mechanics delete the error code (which seems to be a speed sensor code) but it keeps coming back up... When i tell people it's a speed sensor fault, they ask me if my speedo works.. YES!! it works perfectly fine.. Recently i took it down to a mechanic who my friends say knows a lot about import cars.. now he said "the problem might be in the odometer" he took it out and had a look at it it seems okay but he says that the fault must be in that... He thinks that supra's most probably communicate the speed and such from the gearbox speed sensor and then instead of running to the SPEEDO, he thinks it might go to the ODOMETER instead. He reckons that if i replace the ODOMETER reading thing then the problem should be fixed..

Note: As i am driving down steep hills the idle seems to drop faster.

PLEASE PLEASE IF ANYONE KNOWS ANYTHING ABOUT THIS PROBLEM ALL FEEDBACK IS VERY VERY MUCH APPRECIATED....

THANK YOU....

speed sense
 

mate i know that this is a litlle late but if you want to still know what the excact problem is let me know iam a auto sparky from oz

are you still out there
 

i would love to know the problem. i have a diagnosed speed sensor fault that only occurs under load. today i had a new speed sensor installed and my gear oil changed as the mechanic/sparky said he was 95% sure that would fix the problem...has cost me now $500 all up. The lights are still coming on!!!!!!!!!!!! i have a 95 manual na soop. the lights are the only problem, no reving or spedo issues, just the recurrent engine warning lights that goes away when the car is restarted..

i have had enough of this problem. the dealer said to just have the lights diconected and the warranty insurance will not cover the repair.

speed sensor fault
 

be very carfull people that when mechanics not auto sparkys like myself work on your japanese alien space ship that you dont always listen to them when they say iam shure that its the fault when they really have no clue unless tested with the proper gear ,the main problem with the supra is it shits the second speed sender /sensor which is the odometer which yes sends another speed signal to all the other lovely ecus as it cleans the signal up from the source sig which is from the first sensor on the gearbox and if your odo is still counting it can still be stuffed and people who install speed cut defenders and butcher the wires are in for a treat aswell.its the pink wire from the odo that the signal is traveled apon and it will even cause your supra to run like shit at idle and you will never find the damn fault,if any more info needed just pm me but iam in oz so cant look at vehicals,

Yers I'm having the exact same problem, does anybody have a fix ?

Speed Sensor Error Code
 

Hello fellow Supra Lovers,

The Answer is Replace the Odometer Module!! Please read on.

A couple of years ago I had this same dreaded problem with my pride and joy (93 2JZGTE 6Speed).
Symptoms were the same; Cruizing along all ok and suddenly the car felt like it was surging Master Caution Light (The Big Red Exclamation Mark) comes on and the check engine light comes on. Pulling up the car idle drops below it's ideal 600RPM to 300 and running lumpy and then stopping. Re-starting it still lumpy and then it suddenyl all goes away and seems fine.
I took my car to 3 maybe 4 supposed experts (Big Name Tuning Houses) as well as an electrician, no offence to the sparky who replied previously and they came up with 0!
After many nights studying the electrical system and talking to other Supra owners around the world it came down to Three things.
1. Change the speed sensor, 2. Change the ECU or 3. Replace the Odometer Module. Which is the Odometer and Trip meter panel.
Behind all of that lies an interrogator which receives inputs from the Transmission Speed Sensor and Interrogates it and then Translates/Refines this signal to the ECU so the Computer knows what to do! If you read the reccomendations in the Supra Manual for the error code which I think was Code42 it suggests everything except for replacing the Odometer Module and yet the module is the cheapest thing to replace at about 100 buck or less to fix this mysterious problem.
Hope this helps guys..........

the odometer module might just be the problem.

Im not sure the easiness of installing it your self.

I think if they sell the part then you might just be able to do it your self.

um take a visit to this website they have awesome low prices, great customer service, and easy to find parts.
http://toyotapartszone.com

hope this helps!

Odometer Module Replacement
 

2jzmaestro,

The odometer module is very easy to replace and should only take you about 10-15 minutes.
First you have to Unscrew the 3 or 4 Screws that hold the Bottom of the Glare Shield on. Both the odometer Module and the ABS and Water and whatever else warning lights are mounted on this lower panel.
Once you duck down and have unscrewed all the screws very carefully pull the panel out just enough to expose the three plugs attached to the Odometer Module, Hazard Light Relay and the Warning Lights on the Right hand Side of the panel. Unplug them and then you will see that the odometer module is held in place on this panel by a further 4 or 5 screws.
Unscrew them and your're half way there.
With your fresh module repeat the steps making sure that when you plug everything back in nothing gets caught as you push the lower glareshield panel back into place.
Oh and by the way your car will now have 0 Kms on the clock.
Thanks for the web link to the parts.

Cheers mate!

haha I great DIY write up, i especially liked the O kms and the Cheers mate! parts :)

Yah i just bought a new dizzy cap from them yesterday. Hoping to get it today it not monday :( great site though