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Discussion Starter #1
i dont know what i'm doing wrong.i set my ohm meter to ohms 20 k. and connect the negative probe to the black wire on the sensor side of the tps connector block and the positive probe to the blue wire and i get 1.27 i'm supposed to get 4.0 to 6.0.. then i connect the positive lead to the yellow wire and get.75 then when i twist the throttle it goes up to 1.02. its supposed to be .54 to .84 then twist the throttle and its supposed to go to 3.01 to 4.51k ohms. i did this five years ago and i was just within the range now nowhere close. i bought a new tps and these are the readings i get.what am i doing wrong?
 

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Are you sure you are getting a good connection. Here not to long ago I was testing a knock sensor and it kept testing bad. Turned out I wasn't pushing probe into wire enough. Is there any corrosion in the wire that you can see? I know what I'm suggesting is basic for you but sometimes I need to slow down sonetimes.
 

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Completely off subject but Lumberg needs you to come in on Saturday to do those TPS reports....Yeh that would be great...

Sorry it's been that kind of day! Now back the subject at hand....sorry for the detour!
 

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Some DVMs have a little battery icon that comes on when the battery is going dead

will throw all the measurements way off

also if you are touching the leads (holding them) while taking a resistance measurement it will also read the resistance of your body in parallel, and give you a lower reading. Try it sometime, squeeze the leads in your fingers, the harder you squeeze, the lower the resistance it reads.
 

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You are rotating the sensor, correct? You need to rotate the sensor on the sloted screw openings to adjust the resistance. What is the reading with sensor fully slide to one side and then the totally opposite way. The readings will change. Stop when you get between the 4 and 6. A very small movement of sensor can make a big change on reading. Loosen the screws only slightly so friction will hold sensor in place when twisting throttle. Post back your results.
 

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I didn't see in your reply if you have moved sensor full swing on adjustment slots. If you did, what were the difference in the reading?

 

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From wiki:

I had to REMOVE the small round metal washers off the TPS to get the TPS to move a little more for the correct adjustment, follow me on this? I am calling them washers, but there about 1/8" thick and they fit under the screws on the TPS. If you remove them then the TPS will rotate a little more for better ohm setting.

From manual :

 

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The only conclusion I can make is the TPS sensors are bad. Seems like you are doing everything right. With low resistance it would reduce the amount of timing thus reducing horsepower a bit.
 

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Do you access to another meter for a double check?
 

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Were you doing this as a maintenance item of were you having issues? Saw where you posted on the Vstar facebook page. Hopefully Tim or Mick will chime in.
 

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if the meter only goes down to 20K ohms for the lowest range, then 1 k ohm is 5% of full scale

if the meter is really accurate, say 1%, then your error band is+/- 200 ohms

the 10 ohm resistor is .05% of full scale, the meter would never be that accurate - that is down in the noise floor.

To check the meter you will need a 1% 10k or 5k ohm resistor.

a meter with a 2K ohm range would be better suited
 

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Discussion Starter #18
i thought i was getting a clunk on shutdown and maybe the horsepower a little low....mick &tim have not responded, maybe the readings don't make sense to them. i'm going to get another meter, i paid $30.00 for this one at lowes...kcw its a 5% resister and at 2k i get .221.at set at 200 i get 100.2
 
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