Possible IAC problem?

[Lazzman]

I remembered when I replaced my IAC a while back I put on the Napa provided gasket. After reading Aldives above instruction post I realized that the IAC for the Explorer does not need a gasket.

I took it off tonight and found that the glue I used to secure the brass fittings- (I torqed them down way to tight, with bad information and they broke loose) did not hold tight enough. The IAC was not on solid.

I wonder how I can get these brass fittings to bond to the upper manifold again. Would love some suggestions.

Funny thing was that was not the problem. When I took off the IAC I noticed a large piece of silver foiled lodged in the first hole. Don't know where it came from but I took it out with some tweezers and re-installed. Truck idled much better but I still need to find a way to tighten it down to the manifold.

 

[aldive]

I realized that the IAC for the Explorer does not need a gasket.

Say what?

 

[spindlecone]

Brass fittings?????????????
Glue????????????????

 

[Lazzman]

There are metal fittings mounted inside the upper intake manifold that the bolts in the IAC thread into. Last time I replaced the IAC the stupid manual I had said Torque to 85lb ft. Later Al said it was supposed to be like half that, anyway when I was torquing with the wrench it snapped those metal nut type things loose. They are spinning around in the plastic and not letting the IAC screw down tight.

I mean it does not need the gasket that came with it. This IAC is used on lots of ford vehicles some with metal intakes. It was a full cardboard gasket with to holes in it.

Am I supposed to have a gasket with the IAC? The Ford dealer did not use one three years back.

Please help.

 

[aldive]

There are metal fittings mounted inside the upper intake manifold that the bolts in the IAC thread into. Last time I replaced the IAC the stupid manual I had said Torque to 85lb ft. Later Al said it was supposed to be like half that, anyway when I was torquing with the wrench it snapped those metal nut type things loose. They are spinning around in the plastic and not letting the IAC screw down tight.

Can you remove the bronze/brass incerts? You might be able to epoxy them back in place. I have never seen this happen before.

Am I supposed to have a gasket with the IAC? The Ford dealer did not use one three years back.

Yes.

 

[Lazzman]

Yes, they come right out. I did glue them once with a weak glue and it gave way. I am going to use Gorilla Glue this time. That stuff hardens like cement and stays that way forever.

I just have to be careful not to let the glue harden in the screw holes.

Al do you have a picture of description of the gasket? The one that came with mine did not look the the ones in the picture.

My intake does not have the Diamond shaped IAC ports in the above link pictures they are round O rings. I had a full gasket that covered everything even the screw holes.

 

[aldive]

Post a picture of the opening that the IAC covers.

The gasket is Ford # 97JZ9F670AA $4.30.

 

[aldive]

Lazz, what did you pay for the IAC you bought?

The Ford part, 97JZ9F715BA , is $$121.52.

 

[aldive]

I just have to be careful not to let the glue harden in the screw holes.

Put some Vaseline in the screw holes before gluing the inserts into the manifold.

 

[aldive]

Also one mechanic was certain it was the IAC because he said the idle did not kick up when the A/C was turned on at idle. I guess it is supposed to do this without fail.

?

 

[Lazzman]

Al, I paid $92 at Napa the online Ford dealer was about the same but I did not want to wait a week for it to arrive.

Great Idea about the Vaseline I will give it a shot.

A mechanic told me that when the A/C compressor is turned on the idle should jump up a few hundred RPM's.

I threw out the gasket Al so I cannot photo it.

GREAT INFO AL

 

[Derek]

.

 

[karl_burns]

Lazz, I've got the EXACT same thing. Lemme know how your initial repair turns out. I've got an aftermarket IAC in there..... About 3 years old now.....
Karl

 

[Lazzman]

Tested my IAC per the test, passed the first one but failed the IAC ohm resitance test. Could not get any reading on my meter.

Re-glued the fittings with Gorilla glue, flipped over the o ring gasket and tightened down the IAC to spec. No differencein idle, still shudders-still weak.

I am leaning toward replacing the lower intake gasket O rings.

 

[aldive]

Any updates?

 

[Lazzman]

Yes, I ordered the new IAC O ring gasket from Ford. Compared it to the old one and it was about a 1/4" or more wider, so the old one was worn down quite a bit.

I Installed it last week. The Gorilla glue held tight and I was able to mount the IAC like stock. The truck still has that bad frequent shutter at idle which sometimes stalls the engine out.

It is really weird as the engine seems to fight hard to overcome the problem but just stalls out, other times the rpm's dip down to almost zero then catch and shoot up to 1100rpm and then stabilize around 500rpm. It feels like a massive misfire, almost like the engine is seizing up when the shudder occurs.

The O ring did not help the idle but it seems to have helped a very slight bit with the acceleration, don't know how. I am thinking I may either buy a new Motorcraft IAC or get the upper and lower intake gaskets replaced. I still think there is a vacum leak somewhere.

One thing that makes me think the Napa IAC is ok is that it is able to hold a steady idle. Its a weak idle but non the less it still is able to maintain it. The shudder is an occurence that happens intermittently, one episode at a time.

 

[aldive]

You keep mentioning a vacuum leak.

Why have you not tested for one, found it ( if there is one ) and fixed it?

 

[Cleaverkid]

I'm experiencing a similar problem (though not exactly the same) and as a newbie, was wondering if you could give me a high level run through for testing for vacuum leakes. Is there actually a procedure to follow, or is it as simply as tracing each vacuum line one at a time?

Thanks!

 

[Lazzman]

Al,

I have no way to do it myself, no gauges or know how. I am going to my mechanic soon and will have him check for a vacum leak and do a compression test.

I think my intake manifold has an air leak somewhere either in the upper or lower O ring gasket or perhpas the actual manifold is warped somewhere.

Thanks

 

[spindlecone]

Get a can of berrymans, or gumout carb cleaner.
With the engine running start spraying around suspected areas, when the engine stumbles, you have found your vac leak if any.
might just be a simple fix.