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How to Test and Clean your Idle Air Controller (IAC)

A frequent problem with older Broncos is a hunting idle. This is where the engine idle fluctuates up and down and doesn't settle into a stable rpm. As we know, the Ford EEC controls engine idle with the help of the IAC (Idle Air Controller), also known as the IAB (Idle Air Bypass), BPA (Bypass Air Valve) or the ISC (Idle Speed Controller). The IAC is an electro-mechanical device that allows air to be bypassed around the Throttle Plate through a bypass channel. EEC controlled idle rpm can be variable depending on whether in neutral or drive gear and there are modifiers for Engine Temperature, Air Conditioning, Power Steering, Alternator Load, etc.

Regarding engine idle, the EEC is programmed as to how much air is able to pass by the closed OEM Throttle Body Plate. Your factory Throttle Body has a Throttle Plate Set Screw that is locked in place with thread locker. This is to prevent you from adjusting your Throttle Body Set Screw which will throw off this programmed airflow scaler value. If you look, your Ford VECI Label specifically states that your idle is not adjustable and is controlled by the EEC.




In addition to the known closed Throttle Body airflow, the EEC commands an additional amount of air through the IAC in order to maintain a given idle rpm. The IAC bypasses air around the Throttle Body Plate by way of a bypass channel. It does this by responding to an EEC pulsed signal opening an internal spring-loaded pintle and valve seat, hence the IAC is limited by it's operational duty cycle. The EEC then monitors the rpm and if the target is not achieved, it will attempt to make additional IAC airflow adjustments up and down looking for the desired idle rpm. The IAC has limitations and may not be able to compensate for modifications such as over/under adjusted throttle plates, aftermarket throttle bodies, camshafts, displacement and so on. These modifications require that the IAC and/or the TB Scaler be reprogrammed in the EEC or a hunting or poor idle condition may exist.

A poor idle can also be caused by excessively rich idle fuelling from an incorrect MAF Sensor calibration, poorly located Oxygen Sensor, out of range ECT Sensor or vacuum leak. With that being said, a frequent cause of poor idle is a dirty or damaged IAC. Cleaning and testing the IAC is a simple process if done correctly. We take for granted that everyone knows how to properly test and clean the IAC but if not done correctly, it can result in even worse idle issues.



The IAC is located on the side of the EFI Throttle Body.






You may or may not want to remove the Air Intake Tube and Throttle Body Cover for better visual and physical access.








Additionally, you may want to remove the entire Throttle Body Assembly to clean it at the same time. If not, the IAC may easily be removed separately for servicing. I can go either way, depending on whether my goal is maintenance or troubleshooting a poor idle.








Here is the IAC Mounted on the side of the Throttle Body. Unplug the harness connector making sure to not break the locking tab.








Before removing the IAC, use a test meter to verify you are getting battery voltage of at least 10.5v. The IAC is a solenoid/valve that runs on battery voltage, not a sensor using 5v reference voltage. Turn the key on/engine off, place your meter on DC Volts and back probe the harness connector wires. To make this easier, I used my wire cutters to quickly fashion terminals out of extra spade connectors. I inserted the modified flat spade ends into the harness connector and then touched the meter probes to the opposite ends.








Using the appropriate size socket, remove the two bolts attaching the IAC to the Throttle Body. Be very careful that you do not drop them as they will be difficult to locate! Be advised there are gaskets and there may be a Idle Air Bypass Spacer between the IAC and the Throttle Body.








Idle Air Adjust Spacer

Allow me to elaborate on the Idle Air Spacer for a moment. Coking on Ford EFI Throttle Blades has been a problem for many years. If the PCV or vent filter clogs, oil tends to back up and accumulate in the Throttle Bore and plate. This is also caused by blow-by from worn piston rings in older engines. The oil becomes a sludgy residue which eventually hardens reducing the expected amount of air that can pass by the closed Throttle Plate. As less air passes by the closed Throttle Plate, the EEC commands the IAC to increase air flow around the Throttle Plate to maintain a good idle. Eventually, the IAC will approach edge of it's operating range. This is the point where the symptoms of poor idle are experienced and Throttle Body/IAC cleaning are indicated.

To alleviate this problem, Ford developed the Idle Air By-pass Service Kit (F2PZ-9F939-A) for EFI Broncos prior to MY1991. The kit includes an Idle Air Adjust Spacer that corrects sludge contamination concerns on the Throttle Blades to the point that Ford no longer covered Throttle Body Cleaning under the 5/50 Emissions Warranty. A secondary benefit is the ability to fine tune closed throttle plate idle air flow without altering the TPS, which has been very popular with Mustang performance builders having idle problems. The Idle Air Bypass Kit was installed by Ford Dealerships under warranty per TSB 91-25-07 and is still available from Ford as well as aftermarket versions from Tomco and eBay.

Beginning in 1991, Ford began using a Sludge Tolerant Throttle Body design which includes a special slick Teflon coating inside the throttle bore. This coating minimizes deposit formation and does not require cleaning or the service kit. The issue is harsh cleaning can remove the sensitive Teflon coating eliminating the protective qualities. These Throttle Bodies can be identified by a black/yellow sticker on the Throttle Body warning against cleaning or adjusting. Please note that this Sludge Tolerant Design does not include the IAC which may still require servicing or replacement.











After removal, lay the IAC on a work surface. Here you can see the valve body, solenoid and connector locations. Also note that on the under side there are two bypass passages that direct air around the Throttle Body Plate.








Next, we will test the IAC Solenoid. We could have done this earlier on the vehicle, but since we will be cleaning the valve it is easier to do now. Place your electrical meter on "Ohms" and touch the two spades on the IAC connector. Resistance should test in either direction. You should have between 7 and 13 ohms. If you are outside of this range, replace the IAC.








Then test the IAC Solenoid for a internal electrical short. With the electrical meter still on "Ohms", test between either spade on the IAC connector and the IAC body. You should see greater than 10,000 ohms or "OL" (Open Loop). If you have continuity, replace the IAC.






If all tests well, we can dissasemble the IAC for cleaning. Many do not (or cannot due to their particular IAC design) and risk damaging the electrical solenoid with cleaning spray. Remove the screws on both sides of the IAC. They will probably be tight to start so be carefull not to strip the heads.








After the screws are removed, pull the solenoid apart from the valve body. Be sure to remember the orientation of the electrical connector.








Be careful as there is an "O"-ring that may be resting on the valve body. It is normally mounted on the solenoid pintle guide and will pull off. Inspect the O-ring for hardening or deterioration and replace if necessary.






Now lay all of the parts out. You should have a valve body, a solenoid, two screws and an o-ring.






Look inside the valve body and you will see the pintle and port seat. This is the target of our cleaning. Push down on the exposed pintle end to see if it moves against the return spring opening and closing the seat and sealing the internal bypass port. This IAC is fairly clean but odds are yours will be full of carbon.








Now, on to the actual cleaning. This is a critical part as the proper cleaner must be used. Never use brake cleaner which can damage internal seals. Only use Throttle Body or Carburator Cleaner.






Spray Throttle Body Cleaner directly into the bypass channel removing any carbon build-up. Keep alternately spraying and draining liquid cleaner until the majority of carbon is removed. Move the pintle end to raise the seat and spray through the internal passageway. Ford recommends that you limit soaking for no longer than 3 minutes. Be careful not to place anything into the passage ways that may nick or scratch the pintle which may create binding. Shake out any remaining cleaner and use compressed air to dry. When you are satisfied, push on the end of the pintle shaft to test for smooth movement and return.








After cleaning is complete, reassemble the IAC. First coat the o-ring with a light coat of motor oil and replace over the solenoid shaft. Then be sure that you have aligned the connector on the solenoid correctly. Reinstall the two screws securely, but do not overtighten or strip the heads.








Now that your IAC has been tested and cleaned, it is time to reinstall it. Although many reuse their IAC gasket, I recommend that you purchase and install a new one as they are inexpensive. Prep the mounting bolt threads by applying anti-seize paste making them easy to remove in the future. To start the IAC mounting bolts, place a single strip of electrical tape between the bolt and socket and press together. This will hold the bolt in the socket giving you an opportunity to start it in the threads. Otherwise, it will likely drop down onto your engine never to be found again. Tighten the bolts to 71-102 inch lbs. being careful not to over torque.

If you have removed and cleaned your Throttle Body, mount the IAC before installing and also use a new Throttle Body gasket. Don't forget to plug in the IAC harness connector!









***All looks great at this point, but we are definitely not done. Whenever an IAC component is replaced or cleaned or a service affecting idle is performed, it is recommended that the KAM (Keep Alive Memory) be cleared. This provides an Idle Relearn which is crucial to achieving a smooth idle because it permits the IAC solenoid to be brought back within its normal operating range. Disconnect your battery for at least 5 minutes to clear previously learned Idle Air Trim values. Then with all accessories off, start your engine and allow it to idle for at least 15 minutes to relearn the idle strategy. You will slowly hear your idle improve so do not be overly concerned at the beginning. That is, unless you did not test and reinstalled a bad IAC...



One final note, some IACs may be of a vented type having a vent and filter used to equalize pressure within the valve. This type of IAC has a solenoid and valve body which are permanently attached and cannot be separated. These are generally found on OEM Sludge Resistant Throttle Body Assemblies on 1991+ Broncos. It is said that this type cannot be safely cleaned without damaging the solenoid, though many continue to carefully clean them when necessary. Hold the IAC vertically with the Solenoid toward the top to minimize spray cleaner intrusion into the electrical housing. Also ensure the vent port is clear by removing the vent cap and directing spray cleaner through the vent port. Otherwise, this type of IAC should electrically test the same as the non-vented type.



The original vented IAC below from my 1994 F250 tested good and was cleaned. I reinstalled it and it still would not control idle. I again removed the IAC and noted that the pintle was very difficult to move. After replacement with a new Motorcraft IAC, I cleared the KAM and subsequently found a perfectly controlled idle. The point being sometimes an old IAC simply needs to replaced due to mechanical wear, even though it electrically tests good.







Now you are done and it's time for a beer! Not so hard, was it? :beer
 

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As always Seattle, excellent write up. Couple of things:

I noticed you kept the IAC spacer even though you're using a modern BBK TB. I'd expect the newer TB to be sludge tolerant. Guess you're just taking extra precaution.

The throttle body I have on my rig is from a '90. It was cleaned up and slapped on my rig when I rebuilt the engine. No spacer, but I'm assuming it's the non-sludge tolerant variety, I am however using a newer style IAC. Anyway, I noticed that I do have a slight idle hunting until the engine gets warmed up. Wondering how quickly it takes for the TB to sludge up without it and whether or not I'd benefit from one.
 
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As always Seattle, excellent write up. Couple of things:

I noticed you kept the IAC spacer even though you're using a modern BBK TB. I'd expect the newer TB to be sludge tolerant. Guess you're just taking extra precaution.

The throttle body I have on my rig is from a '90. It was cleaned up and slapped on my rig when I rebuilt the engine. No spacer, but I'm assuming it's the non-sludge tolerant variety, I am however using a newer style IAC. Anyway, I noticed that I do have a slight idle hunting until the engine gets warmed up. Wondering how quickly it takes for the TB to sludge up without it and whether or not I'd benefit from one.
jermil01,

I have not seen nor heard of any reference indicating that the BBK Throttle Body is sludge tolerant. In fact, I have a BBK 61mm sitting next to me with no sign of teflon coating in the bore. It appears to be all aluminum. UPDATE: I just received a response from BBK stating that their Throttle Bodies are not tested for sludge tolerance. They state that there should not be an issue with cleaning as long as you do not scratch the Throttle Bore or Throttle Plate. Additionally, they only test for HP gains and not cfm due to the many variables involved.

Many newer ford TBs have a Throttle Plate Orifice (hole) through the throttle plate, supposedly to prevent vacuum lock. I think what it really does is maintain minimum air flow regardless of sludging, kind of like the Ford Air Idle Adjust Spacer. If the orifice is causing too much air causing a high idle, the holes can be plugged with Ford Service Kit (FOPZ-9F652-A). BBK states that they do not require a Throttle Plate Orifice as their larger throttle plate circumference can more easily compensate for vacuum lock. This larger air flow is why an aftermarket Throttle Body should be reflected in your tune. Remember that there is a delicate balance between the EEC Programmed Idle RPM, Closed Throttle Body Minimum Air Flow, TPS Closed Throttle (Ratch) Voltage and the IAC Duty Cycle.

Regarding your idle issue, the first thing I would do is ensure you have a good gasket. Then pop off the vent cap in the IAC. Under the cap is a button filter. Remove them and be sure that the vent port is not clogged. Many have found this to be helpful. BTW, you are using an old TB and you have a new MAF PCM - I wonder if there is a different idle air flow scaler for the expected sludge tolerent IAC??? At any rate, your issue seems to be in the Open Loop Cold Warm-up Strategy.

As you have an older Throttle Body, maybe the Ford Idle Air Adjust Spacer would help. The cool thing about the Spacer is if the TPS is set correctly, you can use the air adjust set screws to make small adjustments to the minimum air flow without disturbing the TPS or IAC. This keeps the PCM informed of proper fueling and allows the IAC to remain centered within it's operating range. The bottom line is some performance builds especially with lumpy aftermarket cams require increased air flow to maintain a smooth idle. This is when you would properly adjust the Throttle Plate Idle Air Set Screw.
 

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While we're on the subject, I wanted to clarify something. In another thread you refer to the "garage" method of TB adjustment. As it relates to the IAC, if you unplug it and your vehicle stops running, I take it that means the TB is out of adjustment. Is that correct?

"I would recommend to you that you try the "Garage" method of TB adjustment by disconnecting the IAC and adjusting the set screw so the engine just maintains an idle. Then try manually adjusting the TPS so you are just below 1v. In my case with the peformance stroker it was .981v, but remember that the increased air flow of my BBK Throttle Body is accounted for in the tune and possibly so is the TPS voltage. I would then do a EEC reset, idle for 15 minutes and see what happens."
Yes. A good running engine which stalls with the IAC unplugged may indicate the need for a minimum air rate adjustment. At normal operating temperature, the engine should maintain an idle with the IAC unplugged. This should be below your EEC programmed idle placing it within the duty cycle of the IAC. The minimum air flow idle (IAC unplugged) will vary with engine type and condition. It should be somewhere around ≤600 rpm and the IAC adjusted rpm should be somewhere between 650-800 rpm.

On another note, I have read that there are there are several types of IACs; Stepper Type, Duty Cycle Type (Ford) and DC Motor Type (Cadillac). Simply unplugging your IAC may leave it in a partially open position, especially if dirty. One should remove the IAC and block the ports with tape or a solid gasket before adjusting the Minimum Air Flow at the Throttle Plate to confirm that you are accurately adjusting only minimum air flow rate. My issue with this is that a Ford IAC is a Duty Cycle Type that responds to pulses from the EEC and then returns to a closed position by way of a return spring in absence of a signal. In other words, I do not think it should matter as long as the IAC is working, clean, and unplugged. Yet confirmation is always good, especially if you are having idle adjustment problems.

I have read that for MAP systems, the IAC bypassed air increases the measured MAP. MAP systems do not measure air flow as it is inferred through this process. The EEC thusly sees increased MAP and increases fueling accordingly. For the MAF system, the bypassed air increases the MAF signal. This is shown as increased measured air. With MAF, the EEC more accurately sees increased air flow and increases fueling accordingly.

Alternately, at idle there is a known minimum air flow scaler. The EEC has a target rpm and simply adds IAC air flow (which could include additions for load) to the known minimum TB air flow to determine air/fuel ratio. This is where problems occur - when the known minimum air flow is not what is expected. The EEC sees the subsequent incorrect idle rpm and attempts to adjust it further with the IAC. If it is above or below the IAC duty cycle (0-100%) it struggles to achieve target idle. Remember that the IAC rapidly pulses and can adjust upward (maybe 600 rpm at 100% duty cycle) but downward only until fully closed.

Significant engine modifications that affect air flow, (such as Heads, Cam, larger MAF Sensor, BBK Throttle Body, K&N Intake, etc.) can also create air/fuel ratio and idle problems. Along with minimum air flow adjustment, these changes should be reflected in the tune, or EEC programming. I believe these air flow changes are largely reflected in the MAP or MAF function. As an example, my MAF Transfer Function is accurately reflected in the tune where others are less accurately reflected in the sensor calibration.
 

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I am working on my 1988 Bronco with a 5.0 and these symptoms seem to fit. However, when I look for the battery voltage with the key on and engine off I have nothing. The wires looked to have been taped up so I thought maybe someone had worked on it and so I stripped all of the tape back and found some really bad looking splices and a diode. That's as far as I have gotten. Any advice on how to proceed?
 

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Discussion Starter #6
Repair the splices and retest for 10.5v-12.0v. If still no voltage at the connector, trace the ISC (-) terminal to EEC Pin #21, and VPWR (+) terminal to the EEC Relay.

------------------------------------------------

As a side note on the IAC Diode:

The 1985-1988 EFI 5.0L Bronco used a different IAC with no internal diode. The diode was externally placed between the red and white wires to the IAC connector (see photo below). In 1989+, Ford placed the diode within the internal IAC circuitry.

The Bronco IAC diode acts as a freewheeling, (or flyback), diode that helps quickly turn off the IAC solenoid. Since the solenoid cannot stop current instantly, the flyback diode provides an alternate path for excess current when the coil is switched off. In other words, the diode takes the energy stored in the solenoid's coil when you switch the current off. Without the diode, the energy has no place to go and will cause a significant voltage spike that will damage the EEC. Rapid switching is important to the IAC as it has only two modes (on/off) which constantly fluctuates as commanded by the EEC.

Note the external 1986 IAC diode diagram below that that shows the anode to the red power wire and cathode to the EEC. I believe that this is an incorrect diagram as this is opposite of the 1986 and 1990 Ford EVTM which shows a reversed flyback configuration which is common in many switching coils. Regardless, I have read of 1986 mustang owners installing a newer IAC which also has an internal diode and then having idle problems due to the IAC no longer working. As correct voltage polarity is required on the 1989+ IACs, switching the wires on the IAC Connector to obtain the correct polarity fixes the non-functioning IAC idle problem.

TSB 89-240-4 covers this as follows:

ISSUE: A rough idle created when the air bypass valve (idle air control) is replaced may be caused by a revision made to the valve's wiring harness. Vehicles built before the 1989 model year had a diode in the air bypass valve's wiring harness. The new replacement valves have a "D" marking on the plastic portion of the solenoid, above the connector cap, Figure 1. They have a diode in the air bypass valve. On the air bypass valve used on vehicles built before the 1989 model year, the positive and negative leads are not important to the valve's operation. However, the polarity on the new replacement air bypass valve is important because, if the wiring harness is reversed, the valve will not work.

ACTION: Reverse the wires in the air bypass valve connector and retest the valve. Refer to the EFI Engine Application Chart for engines using these air bypass valves.


1986 Mustang 5.0L External Diode



1986 Bronco 5.0L (incorrect diagram/diode direction)



1986 Bronco 5.0L (note the external flyback diode)



1990 Bronco 5.8L (note the internal flyback diode)



Note the reversed flyback diode (Anode on top, Cathode on bottom)
 

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I have a question regarding the vented or non vented IAC. I see that you said at 1991 they went to the vented part. Do you know if this was on all '91s or only ones with the teflon coated throttle body?
The one I have on my Bronco is the vented type but it is not original. The O'Reilly parts listing shows both available for the '91. Any reason to get one over the other?
 

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I have a question regarding the vented or non vented IAC. I see that you said at 1991 they went to the vented part. Do you know if this was on all '91s or only ones with the teflon coated throttle body?
The one I have on my Bronco is the vented type but it is not original. The O'Reilly parts listing shows both available for the '91. Any reason to get one over the other?
I believe the Hitachi vented IAC is part of the sludge resistant design of the 1991+ throttle bodies. This type of IAC is aided by a vacuum diaphragm. Under certain conditions it has to vent (the vent simply equalizes pressure) to allow the shaft to move. It also has a sealed non-serviceable solenoid and is not designed to be "cleaned" with solvents. When cleaning these type of IACs, any improvement are likely to be short lived.





If you have an original pre-sludge resistant throttle body, I recommend that you use the Hitachi non-vented IAC, such as the Motorcraft CX-1828 (E9TZ-9F715-BA, F0TE-9F715-B1A). This type allows you to separate the solenoid from the valve body for cleaning. There may be mechanical differences which affect the duty cycle, such as spring pressure and vacuum influences, due to having a diaphragm or not. And the Hitachi vented type IAC may be specific to the sludge tolerant throttle body design. Hence, I would use the correct IAC for your throttle body.





See this link: All Throttle Bodies Created Equal? Gettin' Myself in Deeper.
 

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This might be a silly question, but is the IAC open or closed when disconnected?
The Hitachi IAC that Ford uses should be in the closed position when unplugged.

The Ford IAC is a Duty Cycle Type that responds to pulses from the EEC and then returns to a closed position by way of a return spring in absence of a signal. The IAC rapidly pulses and can adjust engine rpm upward (maybe 600 rpm at 100% duty cycle) but downward only until fully closed. With the absence of an EEC electrical pulse (unplugged), the solenoid does not operate and the return spring mechanically closes the pintle shaft. In other words, the IAC has only two positions - open or closed.

This should be mechanically true with the Ford Duty Cycle Type IAC unless you have a weak return spring, damaged IAC Valve Seat or dirty residue preventing the IAC from completely closing.


 

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code 121. 2 years ago when I first got this truck, I was driving it one morning. All at once, it wouldn't take throttle, and when I pulled off to the side of the road it idle real low and died. When I started it back up, the idle would not pick up, and while I was checking things out, I noticed that if I held the throttle up off the bottom, it would throttle back up. So, not knowing anything about these engines, I adjusted the throttle screw. So now, it sets off this trouble code. Come to find out my TPS was bad. I replaced it, and then I started a thread about how to adjust the idle screw on the throttle body (this is still 2 years ago). Someone explained to me, how to adjust it. So I adjusted it, put on the new TPS, and it drove and idled fine, as it is idling fine now. Another thing I did that was a no no, was, put it in a can of chem dip. The sticker was gone off of the throttle body, that is why I didn't know about the idle screw and the chemicals to the inside of the throttle body. I also threw my IAC into the chem dip. Everything got left soaking over night. The IAC doesn't seem to be effected. I did the resistance test on it yesterday and it tested fine. So, now I guess I need to replace the throttle body. My research last night, showed that a throttle body from 94-96 will work. When I install the new used throttle body, is it as simple as, clearing the codes by disconnecting the battery, for the computer to accept and correct the throttle position?
 

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Excellent walk threw here! very much appreciated!
My 1989 Econoline 150 van has the 5.0L in it and it has developed a very high RPM at idol.
I removed and cleaned the idol air control valve. It is working freely and no carbon build up now.
I checked the idol air control valve to be in spec or not... it is in spec..
I removed the EGR position sensor and checked it to be in spec or not, it is in spec.
EGR freely moves up and down.
So I still have this very high idol issue...like 3000 RPM idol!
What do I check now that could be the source of the problem?
Thank you I await your reply.
 

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a update on my issue

I was just outside looking for vacuum leaks. Found none.
Engine starts right away. every time.
If i disconnect the wiring harness from the solenoid of the idol air control, the engine dies immediately.
and I am following the school of thought that.... once you disconnect the IAC, the idle immediately drops to the minimum idle speed set by the"non- adjustable screw adjustment." Once you plug the IAC back in, the idle typically jumps back up to the idle speed the computer wants to idle it at. .... is this correct?

So what would cause the solenoid on the idol air control valve to fully open the by pass air valve and hold it open? ,
and not allow it to close down some in order to slow the idol of the engine? but instead, keep it fully open??
I discovered that, Opening the egr valve manually does nothing to slow the engine rpm.
I discovered that having removed the egr position sensor and manually depressing and releasing and again depressing the plunger on the egr sensor, has no effect on engine RPM. ...wondering if this is normal?
..as i was under the theory of thought that adding exhaust gas to the intake mixture would lower the rpm some?

So, when I disconnect the wiring harness from the solenoid of the idol air control, and the engine dies immediately, .... I have the impression that the solenoid is working. But could it be fully "on" and not operating as a variable movement solenoid, like I think it is designed to be?
if I am correct, then, what would cause the solenoid on the idol air control valve to fully open the by pass air valve and hold it open?

What do the letters: KAM stand for in this thread?

so While I wait for all your replies, I removed the IAC solenoid and applied 12 volts temporarily to the terminals of it, ( on and off again and repeat) expecting to see the plunger inside move. I saw no movement, i heard no clicking. if the solenoid is good, I'm thinking i should have seen back and forth movement of the plunger, am i correct to think this?..would no movement indicate a bad plunger...even though earlier test with the VOM indicated the solenoid to be with in specs?
 

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Great write-up.

Can the Duty Cycle be measured properly during operation, to determine the position of the plunger ?
 
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What do the letters: KAM stand for in this thread?
Keep Alive Memory

Memory Chip in the computer that stores the Adaptive variations of sensors and stored codes.
KAM is deleted when Battery power is removed.
 

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