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Discussion Starter #1
I have a 2000 model year 445 that runs really good but the throttle has about three inches of travel before anything happens from idle. I took the filter off to watch the throttle body valve and it went from closed to fully open but still no increase in rpm. Then as the throttle is moved even further the rpm will climb to normal but in the last one inch of travel. There is no lost motion in the linkage and the cable is tight. Any ideas? Could one of the sensors cause this? That's one of the things I hate about fuel injection is the troubleshooting. A carb may be finicky but you can handle it visually. With FI you have to be an electronics genius.
 

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After looking at the parts breakdown I'd say your map(Manifold Air Pressure M117803) sensor is getting lazy. Its possible that the hose leading to it is cracked and aged allowing leakage so the sensor isn't getting a true reading. I'd look at the hose before buying a new sensor. There really isn't much to the system on the 445 but some of the pieces to buy new are spendy.
 

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Discussion Starter #3
Thanks for that tip. I looked at the diagram and saw so many sensors that I didn't know which one would have that effect on the tractor. I had to replace several short hoses and the long return hose to the tank so you may be right about a crack in a hose. Thanks again.
 

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I fired up my 445 a few minutes ago just to look at throttle positions. It's running smoothly through all positions. From the full down position, the control lever moves about 1/2 inch upward before any rpm change happens. However, it's a very smooth transition. I haven't checked the rpm at wot, but it sounds correct. Is this your situation also?
 

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Discussion Starter #5
I know it's a pain but can you take a look into the MAP and see what the throttle valve is doing during your throttle movement? My valve is moving, after all, it's mechanical, from full closed to opening proportionally with the throttle movement but there is no rpm increase until the last one inch of travel.
 

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I know it's a pain but can you take a look into the MAP and see what the throttle valve is doing during your throttle movement? My valve is moving, after all, it's mechanical, from full closed to opening proportionally with the throttle movement but there is no rpm increase until the last one inch of travel.
My choke valve begins to move after an inch of travel.
 

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I know it's a pain but can you take a look into the MAP and see what the throttle valve is doing during your throttle movement? My valve is moving, after all, it's mechanical, from full closed to opening proportionally with the throttle movement but there is no rpm increase until the last one inch of travel.
Is that last "one inch" a smooth operation from idle to wot???? I sure found a LOT of dirt below my air filter housing!!
 

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Discussion Starter #8
Thanks Mow. My valve does the same but there is no increase in power until about two more inches of travel. My valve is wide open but still at idle. Then it goes from idle to WOT in about one inch of throttle movement. I'm going to check all the hoses and wires going to the MAP and see if that helps. Thanks for getting your hands dirty!
 

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Thanks Mow. My valve does the same but there is no increase in power until about two more inches of travel. My valve is wide open but still at idle. Then it goes from idle to WOT in about one inch of throttle movement. I'm going to check all the hoses and wires going to the MAP and see if that helps. Thanks for getting your hands dirty!
After one season of mowing, I needed to do that! My thought for you is that if you have a full range of rpm's available, touchy as it might be, I guess I'd just go with it. Otherwise, you might end up with a fix it 'til it's broke situation. I know that I've been there many times. Sometimes I end up spending hour after hour trying to make something do as I think it should and end up back in the same place anyway!! Good luck and best wishes for you and your analyzations.
 

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I also have a 2000 (2001?) 445, and while with the throttle all the way back, it idles just fine, I have to push the throttle thru about half it's travel before the engine actually starts speeding up. I never really worried about it. It idles good, and gets to WOT without trouble, so, I am happy. :)
 

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I also have a 2000 (2001?) 445, and while with the throttle all the way back, it idles just fine, I have to push the throttle thru about half it's travel before the engine actually starts speeding up. I never really worried about it. It idles good, and gets to WOT without trouble, so, I am happy. :)
It may just be a characteristic of the machine.
I know that before I purchased my 445, I was mowing with the Cub Cadet GT2550. That machine was shaft-driven to the drive train but had belt drive to the deck (50"). The 445 has the same HP rating @ 22 (Kawasaki) as the Cub Cadet with the Kohler Command. If I was not familiar with the ratings of the two mowers, I'd have guessed the 445 to be more powerful.
 

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It may just be a characteristic of the machine.
I know that before I purchased my 445, I was mowing with the Cub Cadet GT2550. That machine was shaft-driven to the drive train but had belt drive to the deck (50"). The 445 has the same HP rating @ 22 (Kawasaki) as the Cub Cadet with the Kohler Command. If I was not familiar with the ratings of the two mowers, I'd have guessed the 445 to be more powerful. My 445 has a 60" deck.
 

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Discussion Starter #13
I am about to agree that if it ain't broke don't fix it. It idles well and runs at WOT fine too so I can live with that. I have never had a tractor with this issue so I am glad to hear that it isn't that uncommon to the 445. Thank you all for your comments.
 

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I've had my 445 a little over a year and I noticed the 1/2 inch "dead zone" right away but I also took notice that I had full range within that 1/2 from bottom to full top. I'm assuming others also have smooth transitions once it is moved beyond that zone.
 

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Then it goes from idle to WOT in about one inch of throttle movement.
The question I've had all along, that you haven't really answered is this: In that one inch of travel that the throttle is actively changing RPM, are you able to achieve 1/4 throttle, 1/2 throttle, and 3/4 throttle? Or any other speeds other than idle or WOT? If you've got all speeds available, you're in business!
 
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