I have my sled tore down and decided it was a good time to try to figure out this TPS situation.
I feel I've had a bit of a; I'd call it rich/fat bottom end. Slow/Low RPM thru the trees requires a lot of throttle chopping to keep it responsive. Otherwise its pretty fat feeling.
I see many say even with oiler turned up and oil in tank that they don't feel this..so I felt I needed to look into the TPS.
Anyway, the numbers:
I used a 12.05 volt source power supply; this is unloaded/not plugged into a circuit.
Once plugged into ECM+ (orange) and ECM- (brown?), I heard the fuel pump burp for a fraction (tenth) of a sec. Loaded voltage was 12.00 v.
Before even adjusting my throttle bodies and backing off the throttle cable tension I tested the 5v source from the clear plug above the head (that has nothing connected to it) using the red/white wire. I read 5.03-5.04 v.
I then checked the TPS voltage by back-probing the light blue wire (#7) on the bottom ECM connector. I spent a lot of time tracking down the right connector/wire. Its the wire on the outside edge (closer to MAG) of the connector, about in the middle, right next to a yellow/red [yellow wire w/ red trace]. Voltage here (again, prior to adjusting throttle bodies or cable) was .954 v.
I backed off the throttle bodies; on the MAG side there is a allen screw and lock nut (its pretty obvious). Loosened the lock nut, and backed off the allen screw until I saw a gap between screw and throttle body plate. I also backed off the throttle cable adjuster to create slack in the cable. Voltage reading was .755 v.
I proceeded to adjust the TPS (accessible from the PTO side, just underneath the clutch guard, look for 2 phillips screw heads) by loosening the 2 screws and very slowly rotating until I found .700 v. After snugging the screws back up voltage reading was at .701 v.
Then I adjusted the throttle body allen screw back to .940 v. After snapping throttle a few times to verify, I tightened the lock nut. Voltage was reading .939-.941 v.
I readjusted my throttle cable slack, verifying I wasn't increasing voltage at all from the previous .940 v setting.
Just out of curiousity I checked WOT voltage and was seeing 4.18 v.
I also did a TPS sweep, slowly increment throttle through its range, and I didn't see any dead spots. Numbers looked to increase and not stop or drop at any point.
So, my question to the people who know, was my TPS 'way off'? Enough to cause running issues? .954 v at idle setting. .755 v at default setting.
Oh, and what are others seeing for WOT voltages? Anyone else curious?
For reference, this is a 2011 Pro RMK 800 155 with ~3000 miles.
I feel I've had a bit of a; I'd call it rich/fat bottom end. Slow/Low RPM thru the trees requires a lot of throttle chopping to keep it responsive. Otherwise its pretty fat feeling.
I see many say even with oiler turned up and oil in tank that they don't feel this..so I felt I needed to look into the TPS.
Anyway, the numbers:
I used a 12.05 volt source power supply; this is unloaded/not plugged into a circuit.
Once plugged into ECM+ (orange) and ECM- (brown?), I heard the fuel pump burp for a fraction (tenth) of a sec. Loaded voltage was 12.00 v.
Before even adjusting my throttle bodies and backing off the throttle cable tension I tested the 5v source from the clear plug above the head (that has nothing connected to it) using the red/white wire. I read 5.03-5.04 v.
I then checked the TPS voltage by back-probing the light blue wire (#7) on the bottom ECM connector. I spent a lot of time tracking down the right connector/wire. Its the wire on the outside edge (closer to MAG) of the connector, about in the middle, right next to a yellow/red [yellow wire w/ red trace]. Voltage here (again, prior to adjusting throttle bodies or cable) was .954 v.
I backed off the throttle bodies; on the MAG side there is a allen screw and lock nut (its pretty obvious). Loosened the lock nut, and backed off the allen screw until I saw a gap between screw and throttle body plate. I also backed off the throttle cable adjuster to create slack in the cable. Voltage reading was .755 v.
I proceeded to adjust the TPS (accessible from the PTO side, just underneath the clutch guard, look for 2 phillips screw heads) by loosening the 2 screws and very slowly rotating until I found .700 v. After snugging the screws back up voltage reading was at .701 v.
Then I adjusted the throttle body allen screw back to .940 v. After snapping throttle a few times to verify, I tightened the lock nut. Voltage was reading .939-.941 v.
I readjusted my throttle cable slack, verifying I wasn't increasing voltage at all from the previous .940 v setting.
Just out of curiousity I checked WOT voltage and was seeing 4.18 v.
I also did a TPS sweep, slowly increment throttle through its range, and I didn't see any dead spots. Numbers looked to increase and not stop or drop at any point.
So, my question to the people who know, was my TPS 'way off'? Enough to cause running issues? .954 v at idle setting. .755 v at default setting.
Oh, and what are others seeing for WOT voltages? Anyone else curious?
For reference, this is a 2011 Pro RMK 800 155 with ~3000 miles.
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