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2007 Yamaha V-Star 650 Silverado
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Discussion Starter #1
I just bought this 2007 V-Star 650, which had the carbs in the saddlebags, as the previous owner had giving up. I cleaned and rebuilt the carbs thoroughly and put back together. She started fine, I adjusted the idle screw and decided to go for a quick ride around the block. I noticed my engine light was on, and she surged and bogged down when opening the throttle. I putted back home to find out the problem. When the engine light code blinked what appeared to be 5 times slow and 7 quick blinks. I believe it might be the "Throttle Position Sensor" now here's the kicker, when I unplugged the sensor and used my voltmeter the numbers appear to be within range, (unless I'm doing it wrong..) My question is can the TPS still be bad and give me good readings? Any help would be greatly appreciated. Thanks
 

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its possible the connector is dirty or there is a broken wire between the TPS and the ECM

the bogging down is characteristic of the timing not advancing, and the ECM seems to be getting no signal at all (if its throwing the fault code)
 

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2001 VStar 650 Classic
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When you turn the key to the "On" position the check engine light (CEL) comes on for about a second or two. Then the light goes "Off", providing the TPS is adjusted correctly. Is this happening?. If the CEL stays on longer than that, the TPS needs adjustment.
 

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since the carbs were off the bike when you got it, is it possible the connectors are now plugged into the wrong places?

like the carb heater and TPS connectors got crossed, and the ECM is trying to read the throttle position from the carb heater.... ?
 

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2007 Yamaha V-Star 650 Silverado
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Discussion Starter #6
Update, first of all, thanks for your responses. Ok, when I turn the ignition on the engine light comes on momentarily, then turns off, after about 3 seconds, I hear a very slight "tic" coming from where the ECU is. mind you it's just one tic, after which the engine light flicks on for 5 slow blinks, then 7 or 8 fast blinks. it reverts back to 5 slow blinks then 7 or 8 fast blinks. keep in mind, no tic. I believe the tic only happens when I turn the ignition on and powers up the ECU. I'm not giving up on the TPS just yet. gonna use my voltmeter again to check the ranges again. I'll keep you posted.. Thanks again
 

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you can find the factory service manual for the V Star 650 online, posted as a free PDF download

the schematics are at the end of the manual

if you already checked the TPS and you think its ok, look at the schematic and see where the wires from it go to the ECM - makes sure that connector and wires are ok

also make sure the ground wires are all intact and not corroded where they connect to the frame

also make sure the TPS moves when you open the throttle - that the reading changes
 

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2007 Yamaha V-Star 650 Silverado
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Discussion Starter #9
Thanks robbyk, I checked mine and it was at 1.07 I adjusted to 0.76 and that as far as it went. The slider screws were at their end. Don't know whether to put the carb back in and try it or buy a new TPS. I am going to at least plug everything back (speedometer), to see if engine light cleared, if so, I might just put everything back. If engine light stays on, buying new TPS.. Keep you posted.
 

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Super Moderator "Loose Nut"
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Super Moderator "Loose Nut"
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Another thing to check I had happen years ago, the metal sleeve in the TPS sensor had deformed and was giving false readings. It's a metal sleeve in plastic and will elongate with time. That one took me a while to figure out, has only happened once.

94977
 
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2001 VStar 650 Classic
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Thanks robbyk, I checked mine and it was at 1.07
Yeah at 1.07 you were way out of spec.

Don't install the carb back in the bike just yet. Try this, remove the TPS sensor from the carburetor. Pull the throttle housing a couple of times. Clean the rod where the TPS sensor mounts. As per @lesblank suggestion above check to make sure the metal insert did not move and also make sure is clean. Install the sensor back in the carburetor and adjust it to spec.

Be patient, it is going to take you a couple of tries to get the TPS adjusted to spec. A trick I learned when I was working on mine is make sure the torx screws are a bit snug, but not too much otherwise you're not going to be able to move the sensor to adjust it.
 

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2007 Yamaha V-Star 650 Silverado
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Discussion Starter #14
Ok, I'll try that......get back to you guys afterwards....
 

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Discussion Starter #15
Ok, when I took off the sensor, there is no metal insert. leads me to think that someone's been messing with it.
question are we sure there is suppose to be metal insert? because when I look at the ones for sale on eBay, they're all plastic like mine.
94987
 

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The picture I posted was the OEM. I've seen them without insert. Does the shaft fit snuggly to move sensor? Reading looks right at closed throttle, do readings change as you move throttle?
 

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744Ω is good

make sure the resistance between the two outside pins reads between 4,000 and 6,000 Ω (put meter on 20kΩ range)
 

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There you go... .744 is close enough you're within spec, a bit on the high side but not over the .750

Try that, plug the black connector only, no need to connect the white for the carbs heaters. Plug the speedometer electrical connectors, you can do this without mounting the gas tank. Turn the key to the "On" position and see what the engine light does.
 

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2007 Yamaha V-Star 650 Silverado
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Discussion Starter #20
Yes, it does fit snuggly in, and yes the readings rise as I open the throttle. I installed the harness clip to the carburetor and clipped the speedometer cables back on, and turn the power. I still get 5 slow blinks , then 7 fast blinks, then 5 slow blinks, then 8 fast blinks.,and keeps the rotation 5 slow, 7 fast, 5 slow, 8 fast..... I have to get those blinking codes, can't seem to find it on that online manual..
 
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