89Fleetside
Newbie
What is the proper testing procedure for the TPS? Should the three prong plug be disconnected and tested for voltage and voltage increase? Or do you need to test it on the TPS? Or pull the TPS off and test it?
Proper TPS testing procedure
- Thread starter 89Fleetside
- Start date
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Connect scan tool. Turn ignition on. Look at scan tool for TPS voltage. Cycle pedal from idle to WFO slowly. Verify that voltage increases in proportion to pedal movement, with no dropouts or sudden/unexpected voltage changes. Return pedal to idle slowly from WFO. Again, look for a smooth decrease in TPS voltage.
Works best if your scan tool can graph the voltage, so you have a visual reference to the smooth increase in voltage to WFO, and then a smooth decrease back to idle.
You can do all this with a voltmeter/multimeter, but it takes three times as long, and doesn't test the wire harness or the computer's ability to interpret the data. Additional effort for a less-useful test.
As long as the scan tool is connected, you could verify all the other sensors, in about half-an-hour. Or spend all day doing it with a voltmeter, and still not know if the signal is getting back to the computer properly.
Works best if your scan tool can graph the voltage, so you have a visual reference to the smooth increase in voltage to WFO, and then a smooth decrease back to idle.
You can do all this with a voltmeter/multimeter, but it takes three times as long, and doesn't test the wire harness or the computer's ability to interpret the data. Additional effort for a less-useful test.
As long as the scan tool is connected, you could verify all the other sensors, in about half-an-hour. Or spend all day doing it with a voltmeter, and still not know if the signal is getting back to the computer properly.
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89Fleetside
Newbie
The only scan tool I have is the GM OBD I reader that uses the engine light for the diagnostic display. Is there a good one with the right capabilities that isn't an exorbitant price you can recommend.
Got a laptop? TunerPro RT (free or a suggested contribution) and an ALDL cable (~$60)
www.tunerpro.net/downloadApp.htm
www.aldlcable.com/
Some reading/research and the correct .adx file, you're all set
www.gearhead-efi.com/Fuel-Injection/forumdisplay.php?20-GM-ECM-Bins-TunerPro-Definition-Files-Wiring-Diagrams-Tuner-Info
grampadirt
On MEDICARE Officially Old
I totally agree with the Desert Old Guy 
,I was having problems with my TPS and after connecting my lappy and using Tuner Pro Rt and while watching the graph about half way up there was a big 'ole dropout.replaced the TPS and all was well.Delphi of course,no aftermarket crap here.
,I was having problems with my TPS and after connecting my lappy and using Tuner Pro Rt and while watching the graph about half way up there was a big 'ole dropout.replaced the TPS and all was well.Delphi of course,no aftermarket crap here.
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