iAC valve - How to test? Volvo 9454745

[scot850]

I pulled a couple of these knowing they are no NLA. Both were from NA motors. I have removed the pipes and cleaned the valves with small paint brushes and censor cleaner and now it has removed the carbon build up (just 'sooty' not varnish type build up).

Having done that, how do I test it works? I have a 0-30V DC power supply and a bunch of leads with clips. There are 3 pins on the valve, which one or ones to I have to power to make it operate? Is one pin ground?

I had hoped (and may still) get a pig-tail with the correct connector to make testing easier that working with sunken pins.

Any help and guidance appreciated!!

Thanks,

Neil.

[scot850]

OK. Found a thread on line that says the middle of the 3 pins is the load. and the outer 2 are grounds that determine which way the motor turns. I'll try that and see how it works out with the power supply and maybe try to get a connector to make wiring connecting for testing easier!

Neil.

[jreed]

Thanks for the pin out info -- that's interesting and I'm curious to hear what the results of your testing are.
For what it's worth I know that on the IAC valve that failed on my car (twice), the symptoms were low fluctuating idle/stalling during hot weather (>95F/35C). Cleaning out brown deposits in the valve body helped fix the IAC the first time, and it worked great for several years, but the second time the symptoms persisted even after cleaning and I had to install another used IAC valve harvested from the junkyard. My suspicion was that the rotating head inside the IAC was binding up when hot.

[scot850]

Thanks for the information and I will report back if I get this working with the voltage source. It might be another candidate for the heat gun?

Neil.

[scot850]

Once I figure out how to attach a video, I will try to post it here.

However, today, I broke out the voltage power supply and the croc-clips and tried to see if the info on the pins were correct.

Initially I tried the unit I cleaned yesterday as the pipes were removed making the rotating flap easier to see. I clamped it upright in my bench vice, attached the -ve lead to to one of the 2 outside leads and then touched the middle pin with a small screwdriver with the +ve lead attached.

There was a click, but then nothing. Crap, bad unit or info bad. Ok, remove the pipes from the other unit in case I had killed the cleaned unit with too much cleaner. Same process. This time though there was an audible click and clunk as the flap whizzed round to max travel, and removing the lead allowed it to return to a static position. Tried a few times and also tried using the other -ve pin to see if there was any difference but same result. So I am going to say that maybe you need both the pins connected when it is is use and does the iAC via the ECU decide how much grounding each ground has and they work against each other which controls how far the flap opens based on measured parameters? Having both -ve leads attached when doing a simple 'does it work' test makes no sense if my theory is correct on how the unit is controlled. Connecting both -ve leads may just cause it to not move!!?

So, now thinking perhaps I drowned the cleaned unit, it was worth spraying the flap with a little WD-40 and then working it with a wooden tip to see if it was just dry from the cleaning. Sure enough it started to move and after working it back and forward a few times tried the test again. Initially it was noticeably slower to respond to the other unit, but after a few clicks it too started to rotate fully with an audible clunk on full stroke.

Awesome!

So now I am cleaning the 2nd unit but I'm going to try using a variety of large and small cotton buds and sensor cleaner so as to not drown the unit and see how that works. I am amazed though at how much black sooty crud comes out of the valve.

I wonder if that is to do with the oil fumes being recycled by the system, or it gets worse when the PCV is blocking up which forces more oily residue into the intake system and it settles in the iAC?

I will try to see if a 9V battery will make the flap move so that if you want to test if you have pulled, or even before you have pulled a unit that it is working at a junkyard.

I'll update as I get around to this.

Neil.

[abscate]

Parts geek has SMP and Beck Arnley options on the IAC at about $100

[scot850]

They are possibly re-packaged parts, and who knows, may even be Bosch?

I have 2 Bosch (no Volvo labels) that it turned out the check-out person at the yard would have appeared to have forgotten to include. Does explain why my bill was smaller than I figured. That yard does not appear to have a category for the part. The PnP junkyards actually have this part categorized for $35 CDN ($40 with add on fees and taxes). That is still only $30 US but then you have to add your time and gas for your car to buy something that may or may not work. I will try the 9V battery with 2 leads and see if that is a viable portable test option!

At least if it works it gives owners the option of sourcing.

Neil.

[abscate]

Two part numbers found

[scot850]

Interesting, that first part number if you check it on FCP is not for a white block. Only listed for a red block. The ones I pulled were both from P80's, but both were NA motors. One was from a 97 850 NA the other from a 98 S70 NA.

A noticeable difference to the part number you list as the 1389618 is if you look at the inlet and outlet they are at 90 degrees to each other. The ones I pulled are opposite each other also but parallel. The version 1309618 would not work with the pipework.

https://www.fcpeuro.com/products/volvo- ... 40-1389618

This is are ones I have: 9454745

https://www.skandix.de/en/spare-parts/e ... e/1009892/

Checking their listing this only fits P80's and 960/V90/S90 RWD cars

UPDATE: I tried testing the iAC's today having cleaned both parts but using a 9V battery and 2 jumper leads. This has enough power to turn the valve. To do this you need to remove the 2 rubber pipes (inlet and outlet) so you can see the rotating valve, and then use the center pin to the +ve side of the battery and the -ve side to either of the 2 outer pins. If the valve is not stuck or really sticky, this is sufficient to move the valve to see it is not dead. This is not a 100% surefire test, but it is a reasonable way of seeing if it has any life left.

I cleaned one valve with liberal amounts of sensor clean and the small red tube on the nozzle. I then followed this up with cotton buds and cloths. I found this made this valve initially non-operating. However, a dose of WD-40 and a little encouragement to the valve with a small wooden pop-sickle stick (so as not to damage the soft aluminum), the valve soon worked well.

2nd one I tried cleaning with various sizes of cotton buds, but still had to use a spray of sensor cleaner holding the iAC with the inlet and outlet pipes facing downward over a cloth. This seemed to prevent the valve from sticking, but a little WD-40 was applied.

Hope this is of help and or interest!

Neil.

[abscate]

Correct part number added to thread title for search.

That warm feeling of information being searchable forever , ensues.