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Discussion Starter #41
So should I go with replacing the IACV or the throttle body??? The TPS sensor is reading ok using live data key on engine off watching the graph and stepping on the throttle. It's plastic and non adjustable.
 

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I'm not looking at the pinpoint test at the moment, but generally speaking, it appears the IACV is faulty. It's also possible, unfortunately, that the throttle body is now faulty due to the use of throttle body cleaner. I would replace the IACV and see if that corrects the issue. If not, replace the throttle body if you can't find any vacuum leaks anywhere.
 

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Discussion Starter #43
Ok, thank you. Found that parts on amazon are cheaper than going to the parts store. I'll have to wait until it ships. Will update once its installed.
 

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I use straight ACETONE on the TBs and never have had a problem yet, but skills are involved there, Ford has no shop time allowance for that. Much better to charge big money for a part.

I've rebuilt the TBs as well. All the way back to Tempos.

Like said the warm idle should drop some with the IAC off, indicates a false idle due to other issues, leaks, messing with TB aircrack, etc.
 

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Discussion Starter #45
Throttle Body

Ok, so I haven't ordered anything as of yet, wanted to do another once over of the intake manifold and all the associated hoses, make sure I have everything connected up and torqued down nice and solid. When I pulled the IACV and Throttle body this time I decided to try and check them for vac leaks as well. So I did a light test on the back of the throttle body and light was coming through unevenly all the way around the edges of the valve flap. Shouldn't that be sealed up nice and tight against the body wall all the way around?? So I followed it with a water test on the IM side of the TB because of the IACV inlet couldn't do it the other way, and water dripped through. So if water dripped through then air will too, So I'm replacing that first. Secondly the IACV was shut when I pulled it and I've verified it open with KOEO. So I tried blowing into the bottom side of it and it is shut tight. Is there a possibility it could still be bad if the resistance reads good and it's opening and closing electrically with the ignition key???
 

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i realized something toying with my car did you reinstall the o-rings around IAC openings as i found one of my cars had one missing (it turned to dust) i didn't even notice anything until after when i noticed one ring smushed and the other looked ok but both were fused to the intake manifold it also looks like someone tried using a home made cardboard gasket on it on top of the orings that were stuck (orings were probably stuck to the intake prev owner never noticed then slapped a home made one on)
 

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Discussion Starter #47
Artic, When I pulled the IM for the PCV valve and hose replacement the first time, I grabbed all new gaskets for everything including the IACV and TB.
 

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Artic, When I pulled the IM for the PCV valve and hose replacement the first time, I grabbed all new gaskets for everything including the IACV and TB.
wasn't questioning if you did... again i was toying with an intake not to long ago and found that and thought i would share it as a "just in case" [cheers]
 

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Discussion Starter #49
Thanks, figured as much. I greatly appreciate everyones thoughts and ideas on trying to solve this puzzle.
 

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Thanks, figured as much. I greatly appreciate everyones thoughts and ideas on trying to solve this puzzle.
i would pull my intake to look how it is inside but currently the cars stuck and frozen on a berm at the bottom of my driveway and im not breaking my back to get it unstuck it can melt out on its own its on my driveway so its not blocking or harming anyone..

if it was stuck the other way around i would use it as a hoist/ramp as the nose is now like 2 feet in the air but aimed at the city road and i dont think i want to hang my legs into the road [hihi]

welcome to canada where most of us have 2 vehicles at all times when one gets stuck get the other out and drive it [headbang]
 

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Ok, so I haven't ordered anything as of yet, wanted to do another once over of the intake manifold and all the associated hoses, make sure I have everything connected up and torqued down nice and solid. When I pulled the IACV and Throttle body this time I decided to try and check them for vac leaks as well. So I did a light test on the back of the throttle body and light was coming through unevenly all the way around the edges of the valve flap. Shouldn't that be sealed up nice and tight against the body wall all the way around?? So I followed it with a water test on the IM side of the TB because of the IACV inlet couldn't do it the other way, and water dripped through. So if water dripped through then air will too, So I'm replacing that first. Secondly the IACV was shut when I pulled it and I've verified it open with KOEO. So I tried blowing into the bottom side of it and it is shut tight. Is there a possibility it could still be bad if the resistance reads good and it's opening and closing electrically with the ignition key???
No. The throttle plate never completely seals off the throttle body. If it did, the car wouldn't start....or run.... With the IACV disconnected, the idle should be just a tad bit above stall speed. The only way that's possible, is if air can seep past the throttle plate.
 

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The IACs can commonly come with a paper gasket instead of the OEM type rubber one. Most people miss the rubber one anyway as it sticks to the intake, if the location can't be seen like on zetec, car owner then assumes there was never one there. Regardless, it is proper to put the paper gasket over the top of the old rubber, using it as a ' groove stuffer' to take up space, then the paper gasket seals exceptionally well.

They do it for cost reasons.

The TBs are easy to warp out of flat at the base if tightened too much, one has to remember he's working with plastic there. If not too bad you can run a finetooth dead flat file over the bottom and pick the part back up as good, and a quick $80 or whatever it costs.

One thing to watch for is that the TB and intake flat for it may not necessarily be dead flat, on zetecs they can have gaps of up to .015" or more in places, the TB gasket being thick enough to make up for that. I myself will also file both the mating flats dead flat to make for more crush and a better seal but you have to be careful on the torque pull-up because the gasket portion that seals the inside of the bypass port can be molded thinner and very easy to roll that over at install time to make a leak with a brand new gasket. I try to push straight down at install and no excess moving the TB around in the mounting hole slack at all. The brass inserts in TB holes are what are set to length, the rest of the plastic flat molding will be close but can vary, the thick gasket there allows for some variance in the plastic part being molded when made and lowers the amount of reject parts greatly. Match TB and intake together with a strong light and get a surprise! It looks totally messed up.

This.................NO!

So I did a light test on the back of the throttle body and light was coming through unevenly all the way around the edges of the valve flap. Shouldn't that be sealed up nice and tight against the body wall all the way around??

That is the TB aircrack and MUST show at least a bit of edge leak light there, of course, if someone has messed with the absolute TB butterfly setting that will be off and causes big trouble depending. There is a screw that sets that but normally it is covered with a plug or glue ot whatever, it gets set to spec at factory then you don't touch it. Could be why the IAC unplugged is not dropping engine rpm like it needs to.

The IAC valve can be shut at removal time depending on how the spring is set on it, some shut completely and some don't. Doesn't matter as it powers up with key on and THEN it is supposed to be correct. You can even mess with it with fingers to be open or shut at install and it ignores that to do what it needs to at power on. All that counts.

Thinking a duratec IAC can be bolted on physically backwards and of course that won't work right.
 

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Discussion Starter #53
Ok guys. So here is the latest. Installed a new throttle body and automatically felt and heard the difference. Idling lower than 700 rpms, and no more hang time on the idle. For good measure and because I ordered it anyways, I went ahead and threw the new IACV in too, can't hurt. The P0507 code has not returned and the car is running like new. Would like to say thank you for everyone's help, and that the big ticket indicator wasn't that the TPS was moving fluidly through the graph but with the TB closed it was indicating 19% and with the new one fully closed it was indicating 15%. It could have been the TPS or the TB itself, either way new TB assembly off of amazon and it's running like a champ again.
 

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Typical TPS is around 20% which is considered zero by Ford. The number otherwise varies, mine show 21% on both and idle perfectly. Every TPS is slightly different and why the PCM has to average them out to then decide for itself what is absolute zero there.

TB issues..............
 

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my Duratec shows 21.3% my zetec shows 16.1% both idle and run fine.. threw on another throttle body on the zetec it was lower the car took some time but eventually learned it and ran fine.

those TPS's go bad easy and get dead spots easy... heres what happens when i get bored and have bad parts laying around... I gut them to learn

this TPS on closed would register .17 about an inch into travel it would suddenly jump and the car would take off like a bat out of hell if it didnt stall first xD

you can see the dead spot

 

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X2..............voltage dropouts are the classic error. They commonly do it at idle since that is where many spend most of the time, the pickup point eventually etches the carbon track picced there to make a no read spot.

They can vary % at absolute idle because the PCM uses an averaging algorithm that determines where idle is at regardless of voltage, at least until the TPS reaches around 1 volt even. Past that the PCM decides the TPS is past idle and moving up and it makes moves based on that. Why it can be helpful to look at dead idle volts.
 

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Altho there is no Adj screw on the Focus stock TB there is a proper way to set the idle

Start the engine , unhook the IACV and engine should die ( if it doesnt you have other issues as well ) Restart the engine and bend the throttle tab that hits the stop screw that Ford glued closed , On stock set the idle to about 600-650 , On after market TB with tune set idle to about 700-750 rpm

Then plug the IACV back in and our idle is properly set

Tom
 
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