Testing throttle sensor/ISC

[_lithium_]

Ok so I pulled a throttle body with the ISC and TPS still attached from the junkyard and tried using the manual and used an Ohm reader to test them and the ISC tested out a small bit above the specs of normality but my issue is that no matter which I test (I tested mine on my car awhile ago) the test is always off but my car runs fine. Is this mean I'm just doing it incorrectly? I'm looking to sell this part and not use it personally so I wanna try and vouch that it does work

[mitmaks]

ISC will have different readings depending on temperature imo.

[davmac]

ISC will have different readings depending on temperature imo.

Not just an opinion - it is fact. The ISC reading with ohm meter will change depending on temperature. The spec is usually given for cold engine where the coolant would be around 20C or 70F. The purpose of the valve is to allow air to bypass the closed TB butterfly valve to control idle speed. It adjusts for cold and warm engines by measuring coolant temperature. Pretty simple and reliable part that is likely good.

[_lithium_]

Yeah looks like my ISC is reading a good Ohm. Is there a measurement of Ohm specs for the TPS? If not, how do I test one that isn't in a vehicle right now and make sure it works?

[davmac]

You can use ohm meter to set the "closed" position which is necessary for proper idle. However to test the output voltage across the range of travel (closed to WOT) you need to have it connected to a power source. The TPS gets 5 vdc reference voltage on one wire (top one). Voltage output back to ECU is from second wire down - yellow. You should get 0.1 - 0.5 Vdc at closed position and 3.5 - 4 Vdc at WOT. If you're just selling it I wouldn't worry much.
The procedure to set closed throttle position is found in the service manual starting at this page.

[kyser182]

What about testing weather a TPS is actually working as intended
Your checking for OHMs right? Not voltage. i have the Chilton book but it clearly says ohms when testing from open to closed position to check for proper operation. im newer to DIY car repair.