Need help 2003 ford 4.6 idles high?

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drifter
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Need help 2003 ford 4.6 idles high?

Post by drifter »

I have a 2003 explorer with a 4.6 engine it has 150,000 kilometers we have had it 2 yrs or so and I always thought it idled a bit high.this is what its doing now when you are slowing down the trans mission downshifts into first hard just before you come to a stop which i'm sure is from the high idle ok and just yesterday when we got home it was 1500rpm in park never did that before today I put a new IAC no change then a new tps nothing with my little scan tool at idle it says Absulute TPS % 18 so I took the 2 tps screws out and turned it back and it was ready 14% at idle and then the engine idles perfect approx. 620rpm the so for now I sloted the tps holes and the scanner says absolute tps 14% at idle and it seems fine I took it for a ride the trans might be shifting a little early now or it was just shifter slower before but it seemed great Now I know this is not a correct way to fix this problem so my question is what the heck is the problem?
there is no vac leaks in the pcv boot or any leaks that I can find but I will tell you the muffler has a big hole or is split and getting louder lately
drifter
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Re: Need help 2003 ford 4.6 idles high?

Post by drifter »

Just took it out for a 45 min drive the trans seems normal the way it shifts to me now might have been just me.But it idles perfect no engine lights on so I don't know why lowering the tps value solved the problem
drifter
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Re: Need help 2003 ford 4.6 idles high?

Post by drifter »

Of coarse the wife takes it out today and calls and says its stalling now
jake197000
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Re: Need help 2003 ford 4.6 idles high?

Post by jake197000 »

disc. iac it should idle way down if not you got a leak or the throttle is open too far.clean the throttle body also.ck the tps voltage it should be about .8 to.9 volts.much above that and computor considers it off idle.that percent load at idle is bs.use voltage.hope it helps.
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Re: Need help 2003 ford 4.6 idles high?

Post by PHANTASM »

CHECK YOUR PCV VALVE just had one of these and the pcv valve spring was weak and allowing a vac leak to happen.
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Re: Need help 2003 ford 4.6 idles high?

Post by EthylCat »

How carboned up is the throttle?

If the tps was that high I would have guessed that the blade was stuck partially open.

You adjusted the tps and now the blade has settled back. (stalling)

Anything above about 1.1v from the tps is considered "part throttle" and the pcm commands the iac open to catch the engine and bring it to idle when the throttle is closed.
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Re: Need help 2003 ford 4.6 idles high?

Post by justahoby »

I have seen the idle air solenoid on a 1999 company vehicle I drove act up.. It was a 4.6l in a f250 (7lug wheel) weirdo heavy half like pos....idle high one day... Second day stall every ther time it stopped... I think we switch out the solenoid or throttle body.. Cant remember was a long time ago... And I sunk the POS in a river in 2003.. Boss almost fired me :lol:
As I'm approaching 40,I still think I'm 20. What the hell is wrong with me?
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