John Deere 445 Stalling, Hesitating, Bogging, Fixed - Finally

[BBO]

I just read all the posts here and am going ahead with the new MAP sensor and air temp sensor. My 445 runs for a few minutes fine after startup hen starts the missing and carrying on which it used to stop but now does not. Its only got 200 hours but 14 years old bought new. Anyone have the part # for the air temp sensor?
Will, thank you for your efforts and thorough explanations. I do not trust the Deere Dealer enough to take it in as they will begin with a complete service for $500 then call me a week later and tell me it still has a miss and what do I want to do?
I've been over everything a dozen times on this mower, I'm very technically oriented and after all that I concluded it most likely is electronic in nature and started surfing. Noticing one gentleman posted he just went ahead and replaced both sensors, I'm going that route as it is apparent that the MAP is queen bee of the hive so to speak.
Awesome

Here you go. This is all the numbers you will need.:drink:
View attachment 445_30-31_Parts.pdf

 

[buickanddeere]

Depending on the MAP. A common digital multimeter can monitor the sensor output to troubleshoot.

 

[claw218]

I was having very similar / same problem with my 445. It turned out to be the wire from map sensor rubbing against the throttle cable. Wear spot almost too small to see. No need to replace the map sensor just fix the wire. Not sure if this bad routing was original or changed sometime later. Re-routed the wire ove the throttle cable and put some plastic tube over the throttle cable as wires are still very close.

 

[beenthere]

claw218
:welcome to TBN

Thanks for adding your info and fix to the thread. Will look at son's 445 for that potential problem.

 

[smithrc]

As you can see, the John Deere 445 Kawasaki FD620D engine runs great until a part fails and then, "Good luck". I have worked on a couple of these that have the spark plugs carbon up, or just one carbon up. In my opinion, the 445 is an open loop system instead of a "closed loop system that has an oxygen sensor which can report the combustion burn through the computer and make adjustments. On the larger Briggs motors, oxygen sensor is now present. Anyway, multiple issues can cause the engine to run rough, carbon up, etc. I even noticed that JD has changed recommendations on which spark plug to use. One plug is further away from the valves (shorter) and the other is longer. Before anyone starts replacing parts put a continuity tester on each wire in the wiring harness and make sure you have continuity. Also check for any bare spots on wires and patch them accordingly. I would add that JD pulled some of these wires so tight with nylon zip ties that it caused unnecessary stretching of the wires. Finally, adjust valves to .10" with cylinder at combustion position. Once you looked at these possible causes, you can start thinking of parts replacement.

 

[RLWoodlief58]

I know this is an old thread but I'm having the exact same issues with my 2000 445. I've already replaced the MAP sensor to no avail. I've also replaced both coil packs and the air temp sensor. I have a new fuel pump to install next BUT I'm seriously thinks of taking it in to JD for a diagnostic before proceeding. I had to pull out my JD push mower. It sat for 6 years under the shelter, filled it fresh gas and the darn started on the first pull.