She's running under full power !

[Rob]

Originally Posted by Steve C

Hi

I saw a post on another VW forum and the guy had all sorts of trouble with his car because the VSS ran off the front wheels and it didn't turn while the car was being dynoed.

Steve

Never though of that, but yeah, that *would* be a problem on the dyno.
Since the front wheels don't turn, the ECU things you are standing still, and won't rev over 3K.
Mine's hooked up to the rear axle anyways

Rob.

[Eatoniashoprat]

Originally Posted by Rob

Never though of that, but yeah, that *would* be a problem on the dyno.
Since the front wheels don't turn, the ECU things you are standing still, and won't rev over 3K.
Mine's hooked up to the rear axle anyways

Rob.

This won't help you since you already have it hooked up, but on my ej22 OBD2 bus I made a little circuit with a 555 timer IC and it spits out a square wave just like the original VSS to keep the computer happy. Basically a VSS simulator. The result is my computer thinks I'm doing a certain speed all the time but I don't get a code and no problems in 30,000 miles. The two things I found that the computer uses VSS for is 1) limits revs when you're not moving and 2) changes the idle air motor so slow the engine down if you're cruising and let the the engine idle down, otherwise rpm drops to quick and the engine dies. Thats my experience anyway.
Just another option that might help somebody

Mike

[Rob]

Originally Posted by Eatoniashoprat

This won't help you since you already have it hooked up, but on my ej22 OBD2 bus I made a little circuit with a 555 timer IC and it spits out a square wave just like the original VSS to keep the computer happy. Basically a VSS simulator. The result is my computer thinks I'm doing a certain speed all the time but I don't get a code and no problems in 30,000 miles. The two things I found that the computer uses VSS for is 1) limits revs when you're not moving and 2) changes the idle air motor so slow the engine down if you're cruising and let the the engine idle down, otherwise rpm drops to quick and the engine dies. Thats my experience anyway.
Just another option that might help somebody

Mike

Mike, that's good info. I want to 'trick' the computer in thinking that some of the other sensors are still there so I can get rid of the CE light.
Can you give me some more info on the IC you used and do you know if it could also be used for the other sensors ?

Rob.

[Eatoniashoprat]

Rob,

The IC I used is just called a 555 timer, its very common. Its a device that can be put into two modes, stable or astable. Astable mode makes it just output a pulse at a whatever speed is dictated by the resistors in the circuit. If you run into problems with your VSS or somebody else wants this info I can make a circuit diagram to upload with all the necessary components.

The only other CELs I get on mine are thing like fuel tank pressure and temperature. If these are the same ones you're getting, they're very easy to trick. Below is info for correcting the two codes I got. I didn't actually go through with this to get rid of the codes because I'm not running a CEL, I just scan it if I notice a problem.

183. The fuel temp info to ecm is wrong. It's expecting to see 4.71v or less. That should be easy to fix, just send 5v thru resistor to that ECM wire. You may have some other sensor that provides the right voltage. Just jump it to that terminal.

463. Fuel level sensor. It expects more than 10.9v with ignition on, around 3v when running. That should be easy fix. See if your current fuel sender provides 3 vdc. Then send that voltage to ecm.

Let me know if you are getting other codes and I may be able to help

Mike

[Rob]

Originally Posted by Eatoniashoprat

Rob,

The IC I used is just called a 555 timer, its very common. Its a device that can be put into two modes, stable or astable. Astable mode makes it just output a pulse at a whatever speed is dictated by the resistors in the circuit. If you run into problems with your VSS or somebody else wants this info I can make a circuit diagram to upload with all the necessary components.

The only other CELs I get on mine are thing like fuel tank pressure and temperature. If these are the same ones you're getting, they're very easy to trick. Below is info for correcting the two codes I got. I didn't actually go through with this to get rid of the codes because I'm not running a CEL, I just scan it if I notice a problem.

183. The fuel temp info to ecm is wrong. It's expecting to see 4.71v or less. That should be easy to fix, just send 5v thru resistor to that ECM wire. You may have some other sensor that provides the right voltage. Just jump it to that terminal.

463. Fuel level sensor. It expects more than 10.9v with ignition on, around 3v when running. That should be easy fix. See if your current fuel sender provides 3 vdc. Then send that voltage to ecm.

Let me know if you are getting other codes and I may be able to help

Mike

Thanks Mike, that's great info! Exactly what I am looking for !.
I'm not running a second O2 sensor, so I somehow need to trick it into thinking that one's there as well.

Rob.

[Jim]

Hey quys..

Do you think one of those might be work to solve my problem??
I have found from a local shop called "Brantz rallymeters"these two sensors

Which of them is the correct one??

Universal speedcable sensor



or this
Japanesse Gearbox




Price each is 50euros.

Thanks in advance,
Jim

[Eatoniashoprat]

Hey Jim,
Check out my previous posts, and if you want those Speed sensors to work, you just need to check the output if you want the computer to actually know the correct speed you are going. The ecu is expecting to see a square wave pulse, with four pulses per revolution of the wheel. The computer considers one pulse to be voltage decreasing to 0V (below 0.1V or something) and increasing to 5V (over 4.7V I think). So if the speed sensor you find outputs a wave you just need to supply it with a ground and 5V from one of the engine sensor power wires and you're all set.

Mike

Originally Posted by Jim

Hey quys..

Do you think one of those might be work to solve my problem??
I have found from a local shop called "Brantz rallymeters"these two sensors

Which of them is the correct one??

Universal speedcable sensor



or this
Japanesse Gearbox





Price each is 50euros.

Thanks in advance,
Jim

[Eatoniashoprat]

Originally Posted by Rob

Thanks Mike, that's great info! Exactly what I am looking for !.
I'm not running a second O2 sensor, so I somehow need to trick it into thinking that one's there as well.

Rob.

Don't worry about the 02 sensor, no tricking needed. Just run the first one. The ecu only uses the first one in closed loop operation, the second one is sort of a 'check' on the Cat Converter, but it doesn't affect how the engine runs. On my van I hooked the second one up but it just sits exposed to fresh air, haven't had a code yet.

Mike

[Steve C]

Originally Posted by Eatoniashoprat

Don't worry about the 02 sensor, no tricking needed. Just run the first one. The ecu only uses the first one in closed loop operation, the second one is sort of a 'check' on the Cat Converter, but it doesn't affect how the engine runs. On my van I hooked the second one up but it just sits exposed to fresh air, haven't had a code yet.

Mike

Hi

Im glad you told us that, I only got the one 02 sensor with my motor, just before the turbo and I was going to source one, no need now.

Steve