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Discussion Starter #1 (Edited)
Morning all,

Saturday, I cleaned the throttle body in my 2005 4.6 GT. Immediately after re-assembly, allowing for the chemical to dry all up, the throttle wants to stay put when lifting off the gas, unless I disengage the clutch. This is while driving. Parked at idle the throttle drops back to idle quite slowly but not as slowly as while the clutch is engaged, which is almost not at all.

I've edited to add that I did search the forums for answers and found so much conjecture, diverse weirdness and drivel that I decided to come in cold.

I did try the trick where you turn on the ignition, with the door open (for beeps), engine off, wait for the beeps to stop, and then slowly depress the throttle to the floor and slowly let it back up. Honestly I got better results swinging a dead chicken around my head in a sack.

There are NO codes, No CEL, no warns at all.

A detailed description of my cleaning methodology follows with no color of my own opinions about which may have been a mistake.

The only part I took off was the main air tube, removing it from both the air box and the TB.

I left the IAC tube connected to the main tube and gently laid the MT up on the intake manifold. I left it there while cleaning the blades & bore. Now they are gorgeous.

I left the ignition OFF. I watched a couple or 9 YouTube videos with conflicting methodology, then opted for OFF.

I opened the blades slowly and propped them open with a small screwdriver handle inserted above the left blade, not painted, not rubber.

I sprayed a moderately liberal amount of TB cleaner in there, enough to get black liquid to dribble out onto my alternator pulley and snaky belt a couple of times.

Used a soft bristled baby bottle brush to gently stroke in and out a few times above & below the blades. (shut up 馃槣)

Then I brushed both sides of the blades with a soft bristled tooth brush.

Sprayed a little more cleaner up in there and wrapped the tooth brush with a clean shop rag and used that to wipe down and dry up the TB.

I left the air tube off for half an hour to allow the chemical to dry up inside the intake stuff, then re-installed it, going back to check the air tube to make sure it was on all the way around both the TB and the air box.

Then I started it up. It took about 10 cranks to get it started which is 9 more than usual.

Once it started I noted that it was idling about 250 rpm higher than the usual cold start idle, but it dropped back to < 800 in an appropriate amount of time.

This morning it is still doing the unwanted very slow rpm drop. 馃槙

Anybody been dere done dat?
 

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Discussion Starter #2
I need to add that I did not clean the MAF yet. After all, the Prime Directive says to Only Change One Thing At a Time.

PS Where is my Sig photo? The cat is ticked off.
 

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Yep.I cleaned my throttle body earlier this year and and had the high idle, unusually long slow rev down (hang) problem. I ended up disconnecting the battery over night to reset the KAM. Reconnected battery. Turned key to "on" position for one minute. Then I started the engine and let it idle til it came up to full temp (rad fan kicked on). Then I turned on the AC and let it idle for about 5 minutes. Turned AC off and went on a "normal" drive city and highway for a few miles and then turned on the AC and drove a few more city and highway miles.

Some amount of slow rev down(hang) is apparently normal.

 

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Yep.I cleaned my throttle body earlier this year and and had the high idle, unusually long slow rev down (hang) problem. I ended up disconnecting the battery over night to reset the KAM. Reconnected battery. Turned key to "on" position for one minute. Then I started the engine and let it idle til it came up to full temp (rad fan kicked on). Then I turned on the AC and let it idle for about 5 minutes. Turned AC off and went on a "normal" drive city and highway for a few miles and then turned on the AC and drove a few more city and highway miles.

Some amount of slow rev down(hang) is apparently normal.

Yep, the slow rev drop is normal because abrupt throttle closure causes a huge spike in emissions. BUT, the nearly never drop I have now is not acceptable.

It could just be a driving cycle count issue, Ford apparently has a really long count.

The normal delay ruins heel-n-toe downshifting though. The normal delay can be removed with robust enough tuning software, but it is illegal. Racer only dyno tunes are probably the only way to get rid of that.
 

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I opened the blades slowly and propped them open with a small screwdriver handle inserted above the left blade, not painted, not rubber.
I wonder if this might have screwed something up, somehow. This is the exact same way I have done it on my car, with no apparent ill affects, but I have seen a couple posts that say you should NOT push open the throttle blades by hand; rather you should take the whole thing apart????

I have been wondering if I might have caused some trouble on my car by doing this; but so far the only "issue" I have is fluctuating idle speed, so I really don't know ???

<insert "shrug" icon here . . . I couldn't find it>
 

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Discussion Starter #6
Jeremy, thanks for the reply. I am going to now try the Kill the KAM technique, in my quest to only change one thing at a time. The video is quite good, it is pretty dead nuts professional.

I have even been wondering if it is a perception problem due to slow deterioration while the sludge built up in the throttle body. Naaah, I used to get much more dynamic braking than I am now, and the tach in the video is dropping at the speed of light compared to mine.

At least I got rid of my terrible missing issue during idle with a well warmed up engine. Cleaning the TB put that to rest.

After draining the power to the KEEP ALIVE thingy, I will clean the MAF. One thing at a time. I was going to clean it all any way, now I just want a solid answer. Which step, if any fixed what?
 

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Discussion Starter #7
I wonder if this might have screwed something up, somehow. This is the exact same way I have done it on my car, with no apparent ill affects, but I have seen a couple posts that say you should NOT push open the throttle blades by hand; rather you should take the whole thing apart????

I have been wondering if I might have caused some trouble on my car by doing this; but so far the only "issue" I have is fluctuating idle speed, so I really don't know ???

<insert "shrug" icon here . . . I couldn't find it>
JBert, We do need a shrug emoji馃榿.

I have even been told to leave the key in the ON position while cleaning the thing. That has to be harmful. And others say to do it while it's running. 馃槺 No way am I going to spray highly explosive vapor at a hot motor!

Why does the thing even need to know what is going on with the butterfly valves when it is powered down?
Maybe I should have unplugged the TB connector before cleaning? I meant to but forgot.

I think it just confuses the TBM program, for the short term, with stored wild data inputs from the throttle movement while not running. You know Big Brother never sleeps. 馃憖
 

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I sure hope a KAM reset/relearn fixes this thing. I鈥榲e recently read of another person who an issue like yours and his was a totally different fix. However, since I know nothing about the specifics of your throttle body/TPS, I won鈥檛 throw un-vetted information out there.
 

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Discussion Starter #9
I sure hope a KAM reset/relearn fixes this thing. I鈥榲e recently read of another person who an issue like yours and his was a totally different fix. However, since I know nothing about the specifics of your throttle body/TPS, I won鈥檛 throw un-vetted information out there.
Very disappointing results just a bit ago.

I took the ground cable off the battery, and proceeded to clean the MAF sensor. I was quite successful with that operation. Not only did the car start easily, and run as smooth a a new car, the RPM's dropped while shifting significantly quicker than before cleaning the MAF sensor. However, upon returning to my driveway we went full circle back to the original problem, the horribly rough slow idle that caused me to clean up the TB in the first place, but I don't have the high hanging throttle any more.

Throwing in the towel for the day. I am going to have one or two Lagunitas Maximus. Maybe I should dip the MAF sensor in the ash pile in the bottom of my BBQ grill. I preferred the hanging throttle to the barely running random missing idle.
 

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Sorry to hear that. I鈥檓 half expecting you to replace the MAF sensor.
 

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@Jeremy Weigel recommended exactly what I was thinking. That said how long did you leave the bat disconnected? Disconnect both terminals and leave for at least 1hr. To drain any leftover power press the brakes for a good couple seconds. I have used this reset methods for a couple things and never lets me down. I think I have even done it for the reason or one similar to what you are saying in one of my old 2006's after a intake install and some other stuff. Worked like a charm every time I have done it.
 

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Discussion Starter #12
Sorry to hear that. I鈥檓 half expecting you to replace the MAF sensor.
I may, but after trying a longer reset period without anything else changing.
 

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@Jeremy Weigel recommended exactly what I was thinking. That said how long did you leave the bat disconnected? Disconnect both terminals and leave for at least 1hr. To drain any leftover power press the brakes for a good couple seconds. I have used this reset methods for a couple things and never lets me down. I think I have even done it for the reason or one similar to what you are saying in one of my old 2006's after a intake install and some other stuff. Worked like a charm every time I have done it.
I left the battery disconnected for maybe an hour. Maybe it was not enough. I read what Jeremy posted and meant to adhere to it but didn't.

Honestly some of the reset procedures I've seen sound like a bit of ceremony but at this point, I'm willing to swing a skunk around my head while chanting hip hop lyrics and shaking a tambourine if it works.馃ぃ

I do still have the original 15 year old plugs, but only 72k miles. Maybe I should change them just to eliminate another variable. When it is running above 750 rpm it runs like a brand new car.

AND my key fobs only work at random. They seem to be sync'ed not working with the rough idle. That may just be me or it is really static interference from the missing ignition (but it would have to be running for that to be the case). I have not done a double blind study on it yet. 馃槈 Starting to ramble there. I'm at work now so have to worry about it later.

Yes, I do sound frustrated but trying to retain a sense of humor.

My regular mechanic is also mystified by the condition. No codes so he doesn't want to throw parts at it yet.
 

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I left the battery disconnected for maybe an hour. Maybe it was not enough. I read what Jeremy posted and meant to adhere to it but didn't.

Honestly some of the reset procedures I've seen sound like a bit of ceremony but at this point, I'm willing to swing a skunk around my head while chanting hip hop lyrics and shaking a tambourine if it works.馃ぃ

I do still have the original 15 year old plugs, but only 72k miles. Maybe I should change them just to eliminate another variable. When it is running above 750 rpm it runs like a brand new car.

AND my key fobs only work at random. They seem to be sync'ed not working with the rough idle. That may just be me or it is really static interference from the missing ignition (but it would have to be running for that to be the case). I have not done a double blind study on it yet. 馃槈 Starting to ramble there. I'm at work now so have to worry about it later.

Yes, I do sound frustrated but trying to retain a sense of humor.

My regular mechanic is also mystified by the condition. No codes so he doesn't want to throw parts at it yet.
If you swing a skunk around your head while chanting hip hop lyrics and shaking a tambourine please and I say please video it and post for all of us here to see.

Hate you are having these issues. I hate odd issues that don't have a straightforward fix. Yeah 1hr should have been enough to reset it if I remember correctly 45-1hr is enough.
 
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"I sprayed a moderately liberal amount of TB cleaner in there, enough to get black liquid to dribble out onto my alternator pulley and snaky belt a couple of times"

Unfortunitely, without seeing the car in person, IMHO, that is the issue... back in the 80's that is what every mechanic was instructed to do and then in about the mid 90's every mfg (foriegn & domestic) changed their procedure.... flooding or drowning until it runs out the TB is NOT recommended because of damage to the e-components. The SOP is to spray just lightly, enough to dissolve carbon/dirt related buildup... nothing more, nothing less.
 

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Discussion Starter #16
"I sprayed a moderately liberal amount of TB cleaner in there, enough to get black liquid to dribble out onto my alternator pulley and snaky belt a couple of times"

Unfortunitely, without seeing the car in person, IMHO, that is the issue... back in the 80's that is what every mechanic was instructed to do and then in about the mid 90's every mfg (foriegn & domestic) changed their procedure.... flooding or drowning until it runs out the TB is NOT recommended because of damage to the e-components. The SOP is to spray just lightly, enough to dissolve carbon/dirt related buildup... nothing more, nothing less.
Actually didn't "flood" the thing. Just enough to wet the blades when closed. That's when it dribbled out. After that I held the blades open with the screwdriver handle and sprayed a little more then brushed & dried. I didn't want it to follow the shaft into the electronics widgets on the sides. At any rate the hanging throttle went away and reverted back to my original issue of very low idle & severe missing at idle.

I am beginning to think my missing at idle issue may be related somehow to large inertial changes like going over large bumps, and/or quick slow to stop even though both the TB and the MAF were quite dirty.

The reason I think there could be a correlation is that my work parking lot entrance is not paved and hugely bumpy. My home driveway has a typical Florida curb drain which is actually a culvert. 99% of the time the car goes into the missing at idle crap after pulling into the work or home driveway areas. I wonder if I have a swinging ground short somewhere.
 

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Actually didn't "flood" the thing. That's when it dribbled out. .
Ahhh.............now I understand!!!!!! 馃槑 yup...sounds like an e-type issue..loose wire/bad/corroded connection or even a component going bad (starting)
 

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Dirty little throttle body!!
Look at you! You finally cleaned it after all these years and now you and your car don't know how to act,
Yes, by all means, change your dirty outdated plugs and your fuel filter, because changing your filter has resolved countless issues for so many people.
Also, make sure your brake light fluid is topped off and your ball joints are intact. Don't forget to sacrifice a small mammal at midnight tomorrow and click your heels three times and repeat, "There's no place like home..........there's no place like home."
No need to thank me Dana, glad to help.
Charlie.馃槑
 

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Discussion Starter #19
Dirty little throttle body!!
Look at you! You finally cleaned it after all these years and now you and your car don't know how to act,
Yes, by all means, change your dirty outdated plugs and your fuel filter, because changing your filter has resolved countless issues for so many people.
Also, make sure your brake light fluid is topped off and your ball joints are intact. Don't forget to sacrifice a small mammal at midnight tomorrow and click your heels three times and repeat, "There's no place like home..........there's no place like home."
No need to thank me Dana, glad to help.
Charlie.馃槑
I am glad you don't need it because I don't know how to express my heartfelt gratitude. Your willingness to help will someday be memorialized in stone. :ROFLMAO::ROFLMAO::ROFLMAO:馃ぃ馃ぃ Those things are all on my list. I am going to pay special attention to my brake light fluid. It's pretty shocking that I never had that occur to me before. Not sure if it is Tesla 3 or Edison 5.2 though.
 
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Discussion Starter #20
馃槅I think there may be some corona virus shut down stir crazy Stockholm Syndrome happening here. 馃槣馃お
 
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