just pulled up an error code for throttle position sensor failure (low). where exactly do I find tps? is it on cat engine or tranny? thanks

The TPS is usually attached to the throttle or throttle linkage at the injector pump.

Look where your throttle cable attaches to the injector pump and you should see a secondary cable attached that goes to a small box, probably about the size 2"X1"X6" it will also have a cable that will have a connector attached to it, the connector should have three terminals.

If the code indicate low, it probably is NOT the TPS but the linkage has worn letting the TPS mechanism go below the required setting. The linkage may have broken but I think you would have other codes. It may require a bit of adjustment or some mechanical connectors replaced or rebuilt.

The throttle attachment point is a very weak link in this system, known for failure.

I could send you a picture of my TPS if you would like. I think they are all the same for 5 speed and 6 speed. if not they would be similar.

does this look like the tps on my cat engine? if so is it specific to cat or generic? thanks

The TPS probably is specific to Allison for those generations of "world" transmissions for that era. The Linkage would be specific to the engine or throttle system it is married to.

I will take a picture and compare later to mine

The part in the picture looks like my TPS. If the other end of the cable is attached to the throttle then it will probably be a go. My TPS also has 3 wires I believe.

thanks for info...bench tested tps for proper low and high ohm readings...when not connected to throttle linkage low reading was too low. Will hookback up with an adjustment to extend cable at idle...then will eliminate error codes and road test.

adjusted cable to give higher reading at idle. all is now working as it should. thanks