Throttle body cleaning and molybdenum

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A few questions about cleaning the throttle body of my Lancer, one regarding molybdenum.

I can find 2 versions of the workshop manual. The first does not mention molybdenum at all, and the other one mentions it and warns against removing it:
  1. http://faq.lancer-club.ru/download/...009-2012/2009/13/html/M113100100137900ENG.HTM
  2. http://faq.lancer-club.ru/download/...009-2012/2012/13/html/M113100100241300ENG.HTM
I'm attaching two photos of the throttle body.

Here are my questions:
  1. Is moving the plate by hand safe? I don't see the manual's instructions warn against doing it, but at the same time I see posts in different forums mentioning that manually moving the plate will result in loss of calibration.
  2. Does my throttle have molybdenum? (From what I can see and understand the answer is yes.) If yes, which areas should I avoid cleaning? Should I avoid cleaning the edge, the perimeter of the plate? What about the plate's axle? I see it's black too. Is it covered with molybdenum?
  3. Is resetting the learned value necessary or is it possible to omit it with the ECU adapting without the reset?

img_20241110_152720_32c7dd13271bd28308f084dd0b74579146d90ca8.jpg


img_20241110_152925_b6bad88715996e3877b8408ebb6f10efca373b46.jpg
 
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I just cleaned my throttle body today. However, I didn't refer to a service manual. I simply removed the throttle body, cleaned it thoroughly with carb cleaner spray and a brush and re-installed it. I pushed the plate open (slowly) and held it while I was doing the cleaning. Then I only let is close slowly. Now that I'm finished the car is running great and the idle seems a lot smoother.
 
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don't force the throttle open when the ignition is on, that's how these get broken.

I don't see and have never seen molybdenum on these. it's a 2 minute job to clean them once the intake plumbing is off.
 
@daniel327

I have some issues with the idle, only when the A/C turns on. I will definitely clean the throttle, but I want to clarify those questions I asked first.

@Jetronic

Well, on different Lancer forums you can see that people had issues when the accidentally removed the molybdenum. For example: https://www.evolutionm.net/forums/e...in/681228-molybdenumnmn-disulfide-grease.html

There are a few similar topics mentioning problems when removing the coating.

I'm not 100% sure if my throttle has it too, but from what I saw I think it does.

The workshop manual has 2 different versions. One mentions molybdenum and the other not. I'm not sure if the Lancer comes with 2 different version of its throttle, without molybdenum and with it from some point and on or if the manual got an updated version because the forgot to mention it on the older version.
 
@daniel327

I have some issues with the idle, only when the A/C turns on. I will definitely clean the throttle, but I want to clarify those questions I asked first.

@Jetronic

Well, on different Lancer forums you can see that people had issues when the accidentally removed the molybdenum. For example: https://www.evolutionm.net/forums/e...in/681228-molybdenumnmn-disulfide-grease.html

There are a few similar topics mentioning problems when removing the coating.

I'm not 100% sure if my throttle has it too, but from what I saw I think it does.

The workshop manual has 2 different versions. One mentions molybdenum and the other not. I'm not sure if the Lancer comes with 2 different version of its throttle, without molybdenum and with it from some point and on or if the manual got an updated version because the forgot to mention it on the older version.
There's one way to clean it without worrying about moly. You can use CRC's MAF sensor cleaner. It will not take coatings off and it will clean the throttle plate. I've used it before on my 2az-fe engine, since behind it is a plastic/composite intake manifold that I didn't want any chance of melting using regular throttle body cleaner that has acetone in it.

And about the throttle body's calibrations, I was concerned I'd bother the computer settings by moving it. What I have done is have someone turn the car to the on position, not started/running, and have them push the gas pedal.. then you can get to both sides of the plate.. haven't had a problem yet.
 
Forgot to add-- I never spray the throttle plate directly, I have these foam tipped swabs I've used for electronics. I spray the foam, then use that to clean the throat and throttle plate.
 
I dunno, presumably this is why I was always taught to use cleaner that specifically says TB and not just carb cleaner?

I'm still confused on the black ring Toyota applies around some throttle plates. It comes off with TB cleaner and if it's gone it doesn't cause the world to end.
 
@researcher

So you clean the throttle without removing it. I was planning to remove it, but I may try cleaning it without uninstalling it and I will see the results.
Mitsubishi's manual instructs to remove the throttle. It also says to avoid spraying it directly with any cleaner. It does not restrict the use of specific cleaners, it just says to spray a cloth and use that to wipe the dirt of the throttle body.

@D60

The black think is probably molybdenum. On a few Lancer forums I read stories of people having idle issues when removing it.
 
the black is exactly in the region that the throttl gets dirty. I was a mitsubishi mech, cleaned these often with just a rag, no products at all. See how dirty the body is beyond the throttle, that's where it comes from.
 
the black is exactly in the region that the throttl gets dirty. I was a mitsubishi mech, cleaned these often with just a rag, no products at all. See how dirty the body is beyond the throttle, that's where it comes from.

What do you mean beyond the throttle? Do you mean the intake?
 
@researcher

So you clean the throttle without removing it. I was planning to remove it, but I may try cleaning it without uninstalling it and I will see the results.
Mitsubishi's manual instructs to remove the throttle. It also says to avoid spraying it directly with any cleaner. It does not restrict the use of specific cleaners, it just says to spray a cloth and use that to wipe the dirt of the throttle body.

@D60

The black think is probably molybdenum. On a few Lancer forums I read stories of people having idle issues when removing it.
yes I haven't removed my throttle body, only cleaned the front and back with a helper turning the car on, pushing the gas pedal down to open the throttle plate. I know you probably can get more cleaned by removing it, but I always liked the path of least resistance, or maybe I'm just lazy.. lol

and yes I'd advise against spraying into the intake manifold, many now are a composite plastic that can "melt" with a throttle body cleaner, most contain acetone. but mitsu is correct in saying that.. I liked the foam tipped swabs better than a cloth, just allowed me to get more leverage to "scrub" anything off the surface.

EDIT: Also as I said before, I have used CRC's MAF sensor cleaner on my throttle body, had the same clean result as the acetone-contraining tb cleaner.. less worry with a plastic safe cleaner like MAF cleaner.
 
the last picture you posted

Oh, I guess you mean on the walls of the throttle, behind the valve.

yes I haven't removed my throttle body, only cleaned the front and back with a helper turning the car on, pushing the gas pedal down to open the throttle plate. I know you probably can get more cleaned by removing it, but I always liked the path of least resistance, or maybe I'm just lazy.. lol

and yes I'd advise against spraying into the intake manifold, many now are a composite plastic that can "melt" with a throttle body cleaner, most contain acetone. but mitsu is correct in saying that.. I liked the foam tipped swabs better than a cloth, just allowed me to get more leverage to "scrub" anything off the surface.

EDIT: Also as I said before, I have used CRC's MAF sensor cleaner on my throttle body, had the same clean result as the acetone-contraining tb cleaner.. less worry with a plastic safe cleaner like MAF cleaner.

Is a hydrocarbons and alcohol based cleaner safe for the a plastic intake manifold?
 
For whatever reason I cannot read the links that you have posted. However, no throttle body cleaner is going to remove the metal molybdenum nor would I expect to find any in such a mechanism. As noted already it must be some sort of lubricant such as molybdenum disulfide. Considering that, you could re-lubricate the mechanism if desired. Plenty of molybdenum based solid lubricants on the market.
 
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What year/engine is this Lancer?
I'm assuming a 2010 with the 2.0 4B11, I doubt the 2.4 4B12 is much different
And yes, it seems you'll need a half decent scan tool to perform an idle air relearn
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For whatever reason I cannot read the links that you have posted. However, no throttle body cleaner is going to remove the metal molybdenum nor would I expect to find any in such a mechanism. As noted already it must be some sort of lubricant such as molybdenum disulfide. Considering that, you could re-lubricate the mechanism if desired. Plenty of molybdenum based solid lubricants on the market.
I was very much wondering this, too. Can "molybdenum" be applied as a paint-like coating, or is it a grease?

Despite any Mitsu links here, I'm struggling to understand how any sort of grease/paste would be expected to seal the throttle plate at its circumference. Sure, it can work very briefly but you're talking about a plate that swings constantly and there's still dusty air passing over that "paste" no matter how good your air filter.

I'm not an expert, just struggling to reason through it with my lizard brain
 
@michaelluscher

It's a 2010 Lancer with the 1.5L 4A91 engine. If you have access please check if it indeed has molybdenum. As for the relearn is the scan toll absolutely necessary or will the ECU adapt to new reality? That's what a Mitsubishi electrician had told me in the past that letting the car idle for a while will make it relearn whatever is needed for the throttle to operate as designed.
 
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