Idle problems

[LeoC2]

I replaced the IACV last week, it has been working fine until today. Now when coming to a stop Moose stalls and won't idle. Could the new one have gone bad so quickly? Could they have given me the wrong one?

I retrieved the old one from the garbage and gave it a good cleaning with degreaser, it was pretty dirty in there. I'll pit it back on tomorrow and see if there is a difference.

 

[Jamesvinar]

TCC solenoid?

 

[MarkVIIIMarc]

I had to clean one once. How did it go for you?

My suspicion unfounded is the K&N filter when new needed cleaned out of the IAC's.

 

[BlackIceLSC]

Leo, try putting the trans in neutral right before you come to a stop and see if that makes a difference.

otherwise, faulty IACV, possibly a bad intake leak, but I'd think you would have a CEL on if it was something else.

 

[LeoC2]

Leo, try putting the trans in neutral right before you come to a stop and see if that makes a difference.

otherwise, faulty IACV, possibly a bad intake leak, but I'd think you would have a CEL on if it was something else.

I'm first going to put the old IACV back on in a few minutes to see what happens. If all is OK then obviously the new one is bad.

What's CEL?

 

[steve]

CEL = Check Engine Light, lay off the grappa LOL

 

[MarkVIIIMarc]

For the ease of labor I'd try a combination of BlackIce's recommendation and your own idea to clean your old IAC and see if that makes a difference.

The following may or may not help I suppose. Just my experience.

In my 98 MarkVIII any ignition caused misses I notice first when climbing hills at 1800 rpms in overdrive. My CEL has never come on for a coil pack failure but under a scan tool it did show a pending code for an individual cylinder. The car was almost unable to drive to the shop to get scanned lol. I have changed the plugs but honestly the old ones were not a problem.

Now in my 97 Aurora I can feel the misses at least as bad at idle. Different seats? Who knows lol. It loves throwing a misfire code. Funny computer programming failure there. I have seen a particular cylinder code and then a multiple cylinder code. If it is more than one they have no faith in telling you WHICH ONES. At least the coil packs are fairly reliably testable with the tools available to me unlike my 98 Mark's coil packs which I rotated about when the 2nd one went bad lol.

 

[LeoC2]

Cleaning the old IACV and reinstalling helped considerably. It still needs replacement but I'm positive the new one was faulty or simply wrong.

 

[MarkVIIIMarc]

Cleaning the old IACV and reinstalling helped considerably. It still needs replacement but I'm positive the new one was faulty or simply wrong.

Good deal. I had one I cleaned also and it replaced another which lasted about a year. With NO evidence I blamed the K&N air filter I had installed just before the 1st went bad. Over maybe 70,000 miles since I have not fooled with it. Hopefully you have similar luck.

 

[driller]

Cleaning the old IACV and reinstalling helped considerably. It still needs replacement but I'm positive the new one was faulty or simply wrong.

My money is the new one was wrong. The parts store(s) have a bad habit of cross-referencing 'wrong' parts. In this case, I think you'd been better off ordering the one from the dealer.

 

[SCTBIRD1173]

Leo, I came up with a Motorcraft CX1851 which Rockauto has for $34.79.

 

[chris2523]

My money is the new one was wrong. The parts store(s) have a bad habit of cross-referencing 'wrong' parts. In this case, I think you'd been better off ordering the one from the dealer.

and they are surprisingly sensitive.
my mach 1 iac which had worked for months no longer worked after cobra cams and longtubes.
switching back to the 96 mark viii iac was a noticeable change.

Leo, I came up with a Motorcraft CX1851 which Rockauto has for $34.79.

its the same price (for me) from amazon after rock auto shipping, plus i get prime shipping, plus i don't have to deal with rock auto.
win/win/win.
https://www.amazon.com/Motorcraft-CX1851-Idle-Control-Motor/dp/B000C5FHUG
amazon ftw.

 

[SCTBIRD1173]

its the same price (for me) from amazon after rock auto shipping, plus i get prime shipping, plus i don't have to deal with rock auto.
win/win/win.
https://www.amazon.com/Motorcraft-CX1851-Idle-Control-Motor/dp/B000C5FHUG
amazon ftw.

Who doesn't have prime these days!? LOL I still tend to buy all my Motorcraft items from Rock as they sell at or below dealer cost on all Motorcraft parts. Rock still comes in cheaper than Amazon at $37.04 with the cheapest shipping and the 5% discount code. I can't argue Amazon as a great choice too though.

 

[LeoC2]

I did buy the Motorcraft from Rock last week and have it kept in reserve. After giving the original a good cleaning it performed flawlessly and still is. I'll just leave it for now and keep the new as a spare.

 

[steve]

I did buy the Motorcraft from Rock last week and have it kept in reserve. After giving the original a good cleaning it performed flawlessly and still is. I'll just leave it for now and keep the new as a spare.

How do you know if the one you got is any good? I would do just the opposite, put the new one in and keep the old one for a spare.

 

[LeoC2]

How do you know if the one you got is any good? I would do just the opposite, put the new one in and keep the old one for a spare.

That's a good point Steve. I hadn't considered that. As soon as the snow clears I'll do just that.