Adjusting the VSS signal to TCU.

Turboscort · New Member Joined: Feb 03, 2007 Posts: 15

The VSS is on speed input2 with senser refrence gound on the TCU. I did a data log and noticed that the VSS isn't reading the speed right. It's way off, like if the car is going 10mph the TCU is only seeing like 1mph. It's a basic VSS senser 2 wire hookup with a 22 tooth gear. I've been threw the manual a few times along with going threw the setup files and my eyes are glazeing over. What settings do I need to adjust to correct this? I don't want to just randumly start changing setting and make things worst.
The RPM's read correctly and I think the turbine speed is reading close to right.

Russ · PCS Employee Joined: May 12, 2004 Posts: 286

VSS is calculated from driveshaft RPM, Final drive ratio, and Tire diameter.
If your sure the sensor has 22 teeth then change the Pulses Per Rev for Drive Shaft RPM to 22. The next thing to figure out is where the VSS sensor is located. If its located after the differential, like on the output shaft housing, then set your final drive ratio to 1.0. Otherwise set your final drive ratio to what it should be and adjust your tire size until it reads correctly.

Russ

Turboscort · New Member Joined: Feb 03, 2007 Posts: 15

I had an extra VSS senor for the car in my tool box, so I just counted the teeth on it.

I'll look threw my manuals for the location of the senor. I'm pretty sure it is located after the differentialon the output shaft housing. I know it's real close to the diff, might be next to it, but it is in that area.

Turboscort · New Member Joined: Feb 03, 2007 Posts: 15

I had to set it to .4 before it started reading the speedo right. It shifts 1st 2nd and Drive. I don't think I got up to sett enough for OD to kick in.

Russ · PCS Employee Joined: May 12, 2004 Posts: 286

Make sure the shift indicator on the monitor screen shows D when your in Drive. If it shows 3rd then you only be able to go to 3rd gear.

Russ

Turboscort · New Member Joined: Feb 03, 2007 Posts: 15

My friend was maning the laptop while I was driveing and we didn't data log that run but, the shift indicator on the monitor screen was showing that the postion was OD which was what the leaver was in. When driving with it left in OD position, it would shit from first -> second -> third on the screen. I don't recall if we hit forth (OD). I don't think we did. I figured we sould have been at a low enough rpm cruise for it to hit forth. We were just makeing short trips around the block since the car hasn't been drivable for a while and it has no insurance, registration and inspection at the moment.