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Old Phart
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Looks like an interesting option over using a normal OBD code reader/scan tool, IF you've got the spare Win 7 laptop to use with it. The other less satisfactory method is an ELM clone used with a smart phone.

NO you can't use something like that for Ford direct linkup, that's a paid service NOT avail. to just anyone for free. The better/more expensive IDS tool setups often include a short term license to that service according to their advertising.
 

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Correct, flashing PCM is a web service now and you need a subscription for that. Although it will have some of the older calibration files that probably don't apply to your model year. In any case I don't recommend flashing with this knock off device as PCMs are expensive to replace.
It will only work on Windows XP and for that you will create a virtual machine. It should come with all the instructions, poorly translated at times. If you do end up getting it and need tech help, let me know.

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Discussion Starter #25
Thanks again for all the help. After going through this whole process, only thing I can find is the parameters for the throttle body are off, and will not stay constant. I will be replacing the throttle body later next week, and then full reset to see how she will react. Fingers crossed!
 

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If it happens when your AC is on and you're low on refrigerant, and it's constantly cycling the clutch on and off on the compressor it can cause some idling issues.
I actually had a idling issue on my car recharged my AC system that was low haven't had a problem since.
Not saying you are low on refrigerant but a constantly cycling on and off compressor clutch can make a unpleasant idle situation.

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The refrigerant pressures are correct / in range. The idle fluctuation is not in rhythm with the engagement / disengagement of the AC clutch. That is if the AC is constantly engaged, the idle is fluctuating from 500 to 1000 RPM.
 

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All maintenance is up to date. I have also replaced the TB and MAF with no help. I have removed the battery for a couple hours to try a reset. I am not sure how to check the TPS?
 

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A vacuum leak will make the TB chase it all around as it tries to correct for it similar to what the older IACs do. Just got finished with a Nissan with the same problem, found the leak and problem quit. In that case the TB was locked against the off stop as it was trying to go lower than the stop would let it go in an attempt to lower the idle speed.
 

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If it were a vacuum leak it would roam at any idle load or not. My issue only happens with load like AC or quick turn of steering. Without load, it idles fine.
 

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'If it were a vacuum leak it would roam at any idle load or not.'

You'd think that, but then you would likely be wrong. There are so many ways they can present it is not funny. BTDT.

There is not a lot of idle trim fuel range on these. When the engine lowers rpm more the IAC has to open more trying to correct it and the PCM has to add more fuel to cover that, it can then hit the idle fuel trim limit and motor goes whacky because there is no more fuel. At normal idle speed the IAC has to add much less air, it may even have to take away air because of the leak and the fuel trim then covers it.

Some of that depends on where the TB aircrack is as well, that physical location is closely linked with IAC ranging, whether it has to go high or low to control idle speed.

You can have a vacuum leak, and as long as it is within fuel trim range the PCM will accept the fast speed and simply drop it back to normal using the IAC. Once you pass the fuel limit is when the leak begins to mess the idle quality up in roughness. You get closer to that the more the IAC has to open, or the bigger the vacuum leak gets.
 

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You get closer to that the more the IAC has to open, or the bigger the vacuum leak gets.
As stated, there's no IAC on 08-11 cars.

Check your alternator/battery health. Roaming idle is constantly coming up as a common 'issue' on these cars though I have never ever seen it on my 11 SES with over 100k miles.

My "educated guess" would be that there's some electrical issue stemming from the battery/charging system that causes issues with idle.

Battery and alternators are free to check at most auto part stores everywhere.
 

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See, I'm having an issue with mine dropping way to low and my car stalling while in park or at idle and then park and idle when my rad fan kicks on it's like my engine takes a fat hit of crack and losses its shit until the fan shuts off
 

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I will say do not use an aftermarket throttle body. I made that mistake ( an expensive one at that) my car would get stuck at 1500 rpms when ever I'd rev the engine and ultimately never fixed my idle hunt either
 

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There is no difference in IAC type engine idle control or TB only, the electronic TB has to move the butterfly in the same way the IAC moves a pintle.

Just fixed a Nissan electronic TB with no IAC using the same ideas.
 
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