MX MPI Horizon 6.2 throttle body clean

[scrumper]

Risking a flaming for a dumb question here but do I need to remove the throttle body on this engine to clean it?

Having some slow idle & stalling problems and on inspection it’s pretty carbonized and the IAC muffler sponge is disgusting.

So I’m wondering if throttle body cleaner is safe if it drips into the intake manifold or whether I should just not risk the shortcut and take the extra time to pull the throttle body before cleaning it.

 

[Brite Idea]

I just did the same thing. I didn't remove the throttle body but did a good cleaning with throttle body cleaner. The flame arrester was filthy and took some time to get clean. Be sure to change the IAC filter but don't spray the IAC. Mine worked out great afterwards I have a nice smooth idle again.

 

[Espos4]

Risking a flaming for a dumb question here but do I need to remove the throttle body on this engine to clean it?

Having some slow idle & stalling problems and on inspection it’s pretty carbonized and the IAC muffler sponge is disgusting.

So I’m wondering if throttle body cleaner is safe if it drips into the intake manifold or whether I should just not risk the shortcut and take the extra time to pull the throttle body before cleaning it.

If you clean it still installed, just leave the throttle wide open without the flame arrester for 30 minutes. Most of it will evaporate and it should start relatively easy. You may have to use the “clear flood” procedure if it doesn’t start.

 

[scrumper]

Thanks Espos4 and Brite Idea, that's encouraging and thanks for the advice. I get the cleaner can evaporate; what about the sludge that I'd be washing off?

EDIT: starting to really like this idea of doing it in situ, the little TB gasket is $77 each side!

 

[scrumper]

That worked a treat, thanks guys. Shitty 450rpm idle is no more. (Now it’s too fast but that’s another post! I expect the IAC cooked itself trying to compensate for all the gunk.)

 

[scoflaw]

Squirt some cleaner in the IAC opening while it's running that'll probably clear it off

 

[James Lee]

Having same issue here inspected the flame arrester and it was very dirty. Cleaned it and replaced the muffler/filter. Replaced the IAC with a non OEM part. From Amazon it was only 35 bucks. Still stalling. And still getting check engine alarm “bad sensor”. I did notice the throttle body was pretty gunky too. So just asking again. Is it ok to clean throttle body while still on and engine running ?

 

[scrumper]

You gotta use an OEM or equivalent IAC; the cheapo automotive ones don't work the same way and aren't compatible in practice even though they look the same.

Can you borrow a diagnostic tool (Rinda Diacom) to figure out exactly what sensor it thinks is bad? Have you got another thread about your issue?

I can't think of any reason to clean it while it it's running. You could; it'll run very rough and smoke horribly. But it won't do it any good or show you anything you won't learn by stopping, cleaning, and re-starting. And yes you can absolutely clean the body without removing it. But in any event, a bad sensor code most likely isn't going to clear itself just by scrubbing the throttle body.

BTW my original post in this thread was the start of a journey that ended up with finding water in the engine and having to a top-end rebuild. I learned a ton about my engines in the process but it wasn't an easy time. I hope for your sake it's not that!

 

[James Lee]

Thank you. Yea it ended up being just the IAC valve. Marina didn’t have merc brand, had to go with the sierra off brand. It works fine now. Cleaned the throttle body with throttle body cleaner. I simply sprayed on throttle body and wiped clean. Purring like a kitty now.

 

[scrumper]

Nice, glad to hear it. Sierra part works fine - it's marine application - just not rando thing from Autozone