Gary Lewis Posted March 24, 2019 Share Posted March 24, 2019 Next question. How could i test - diagnose TPS? You use a digital voltmeter and check the voltage as shown in pic below, which is from the the link above. I believe that Vref is the orange/white wire, Signal Voltage will be the dark green/light green wire, and Ground is the black/white wire. You will have to guestimate the angle, but if I'm right the TPS is going "open", meaning not providing an output or signal voltage just off idle. So I wouldn't worry about making sure that the signal voltage is spot-on at all the angles. Instead I would concentrate on what happens as you open the throttle. Does the voltage increase smoothly or does it go to zero and then come back at some point? This is Page 57 from the 1986 EVTM, and you can see the TPS at the top left. Link to comment Share on other sites More sharing options...
jarek_rugby Posted March 24, 2019 Author Share Posted March 24, 2019 You use a digital voltmeter and check the voltage as shown in pic below, which is from the the link above. I believe that Vref is the orange/white wire, Signal Voltage will be the dark green/light green wire, and Ground is the black/white wire. You will have to guestimate the angle, but if I'm right the TPS is going "open", meaning not providing an output or signal voltage just off idle. So I wouldn't worry about making sure that the signal voltage is spot-on at all the angles. Instead I would concentrate on what happens as you open the throttle. Does the voltage increase smoothly or does it go to zero and then come back at some point? This is Page 57 from the 1986 EVTM, and you can see the TPS at the top left. Gary, I checked TPS. It is OK. Now i have to check idle :) Link to comment Share on other sites More sharing options...
Gary Lewis Posted March 24, 2019 Share Posted March 24, 2019 Gary, I checked TPS. It is OK. Now i have to check idle :) Good luck. Has it been giving you problems any more? Link to comment Share on other sites More sharing options...
Steve83 Posted March 25, 2019 Share Posted March 25, 2019 Gary, I checked TPS. It is OK. Now i have to check idle :) This caption has more detail about the TPS: https://supermotors.net/getfile/173616/thumbnail/tps-graph.jpg This caption explains the idle: https://supermotors.net/getfile/231296/thumbnail/iac-cutaway.jpg Read that whole caption before attempting to diagnose or adjust anything. Note that it mentions the TPS as a cause for poor idle quality. Link to comment Share on other sites More sharing options...
jarek_rugby Posted March 25, 2019 Author Share Posted March 25, 2019 Good luck. Has it been giving you problems any more? No, just this 2 times Link to comment Share on other sites More sharing options...
Recommended Posts