John Deere 445 stumbles on cold start

[olgreyhair]

That's a good idea. Another theory I need to pursue is that of a leaky injector. If the injector was to leak fuel into the manifold would it not act like it was flooding on cold startup? If it starts and stumbles, it act like excess fuel. And when it fails to start and floods, I clean the plugs and crank the engine to clear the excess fuel and then it runs fine. What if the injector is leaking and I'm starting with excess fuel in the manifold before I even hit the key? That would explain why it's only at cold startup. The rest of the day there's no excess fuel in the manifold. How do I test a for a leaky injector? G.

 

[BBO]

How do I test a for a leaky injector? G.

Maybe someone else knows, but I was never able to determine if raw gas was inside the throttle body after sitting or after the pump ran for those 2 seconds.
You can check the ohms on the injector. I can't remember but seems like mine was like 12 ohms.
Someplace I read where you can put 12vdc on the injector to see if it clicks.

You can also check the voltage getting to the injector to be sure it's the full battery voltage.

There is a ton of items here involved. Expensive sensors, loose grounds, wiring harness connections, the injector module etc.
Hopefully you will not need to get into all this.
Remove the seat and 6 bolts that hold the rear fender deck on. Take the tail light bulbs out and the seat switch if you have one still.
Unscrew the fuel pump cover and be careful with the large o-ring underneath. You may need a new one..
Then pull the fuel pump up to check that $2 section of hose.

 

[olgreyhair]

If you get into the injector body they sell a throttle body kit. Orings and stuff in case anything is loose...

I took mine all apart and cleaned everything. If you do this you will learn how it works.
The injector has 2 o-rings and the inside is smaller/fat .
IF this beefy o-ring leaks, it could let raw gas into the throttle during that 2-second pressurization.
I ordered & replaced both of those small o-rings on mine.
It can also let gas seep into the throttle after the engine is shut off. (It would be like a leaky injector)
Also I would suggest you replace all of the small hoses & clamps before you start buying expensive sensors.

You can check the resistance in the MAP sensor if you have a good multimeter.
View attachment 388233

Thanks BBO. I'm starting to think you may be on to something. It does act like a leaky injector. What is the throttle body kit that you speak of? I see I can order the orings, but what else is in the kit?

 

[BBO]

Thanks BBO. I'm starting to think you may be on to something. It does act like a leaky injector. What is the throttle body kit that you speak of? I see I can order the orings, but what else is in the kit?

JD # AM118232 Kit. It was about $32 in 2010


But... This does not include the o-rings for the fuel injector. The kit has a few o-rings mainly related to air flow vs. fuel.
It does have the main throttle gasket and gaskets for the water temp sensor and that grommet that the air temp sensor pops into.
What did the hose above the fuel pump look like?

 

[olgreyhair]

Prolog.
I have found my problem. After all that and then some I noticed the engine bubbles thru the coolant overflow tank. Head gasket time. I was always working form the left side of the tractor I guess and never noticed the bubbles in the tank. Didn't have time to tackle that one so I brought to the local JD dealer.
Thanks for all the help and suggestions everyone. G