FIX for long time VSS issues

[somedude_001]

Whiteguy93 bought my turbo SHO a while back and at that point I still had not figured out why the VSS would only read over 40mph but drop signal under that speed. He swapped the trans in his car and it worked perfect then about a year later he called me to bounce come ideas off my head for trouble shooting the same problem that was now occurring on his car. the 1 foot long section of wiring that goes from the VSS to the connector by the rear O2 connector had melted on both of our cars. apparently the heat shields the factory put there are actually needed go figure.

I felt like a bit of a jack ass when he told me that because I replaced the PCM, the sensor, the wiring from the ECU to the connector by the O2 but for whatever reason did not replace the short section that runs between the exhaust and the transmission. Learn from our mistakes and DO NOT remove that heat shield protecting the wiring there.

You can thank Whiteguy93 for finding this.

 

[kevinspann]

And St Louis SHO for pointing him the the right direction in his thread.

 

[whiteguy3]

Thanks Alex. I know it's frustrating to find out, but I know it's better to find out now then never.

With the help of a couple suggestions on here, Alex and some real digging into both cars in my driveway the issue was resolved. I knew it was not an internal trans issue, but was just so surprised it was actually a VSS issue. The suggestions on here just helped to confirm what I was already hating to admit.

I have a VSS heat shield on it's way and am probably going to modify it to keep temperatures down. I have the room to do so since I have a relatively small motor mount back there. I am also going to get some heat protective wire loom for that wiring section from the VSS. Then the exhaust manifolds will get heat wrapped when the turbo goes in. There should not be any issue at all when that all gets finished.

Alex did a good job of keeping temperatures down on his turbo ATX. I intend on using some of his ideas on my project. If anybody is interested the turbo up-pipe will be run underneath the subframe after it is notched. A semi-circle will be cut from the subframe and replaced with a 4" semi-circle piece of piping and welded in place. That allows the piping to be easily accessible and it is one of the only ways it can be run with the GEN 3 subframe.

The trans cooler is directly behind the Ford emblem and has a fan mounted to it to pull cool air through it. The fan is on a switch mounted inside the car. Just some info for those that might be interested.