Signs of bad IAC?

[urban96]

well since the search is disabled i thought i would make a new thread

Sometimes my car starts right up first try, sometimes itll crank and crank and i have to press the gas pedal to get it to fire.

Would this be caused by the IAC ( idle air controller )?

Or is it just my larger injectors needing less cranking fuel. Only running 24lbers so i dont really think thats the cause



:SNSign:

 

[Blackened302]

don't know about the starting issue, but if you want to check your iac, simply unplug it w/ the car idling. if it starts to sputter/run like crap, it's probably working. (plug it back in and it should idle fine)

 

[HGFireHazard]

You know that's interesting, because I have a very similar issue. The majority of the time the car starts up without a hitch, but there are these few times where I can let it crank and crank but it won't start unless I floor it.

I know doing that turns off the injector pulse, but I wonder if there is some common link to this?

 

[HISSIN50]

Is there any rhyme or reason (i.e. it happens when the engine is hot vs cold)? The cranking fuel theory would come into play on a hot motor (and I agree with you that this is probably not likely based solely on 24's).

An ECT out of calibration can cause a similar issue. Remember it's a thermistor if you decide to test it's voltage and/or resistance.

You could see if the bleed screw is run all the way in for some reason. Otherwise, I'd go ahead and clean the IAC anyhow.

I dont like folks to open cans of dog poop but if you ever find the need to hose with the idle, I might set it like I do: I set the hot, no load idle with a zero IAC DC. Ergo I don't need the IAC for the car to idle hot and without a load. This is my preferred method.

Good luck bud.

 

[urban96]

starts up great after it sits overnight or has been sitting for a while. also when its cooler out it starts easier.

now that i think about it these problems started occuring last spring after i replaced my ECT. maybe ill try putting the stocker back in.

 

[urban96]

Is there any rhyme or reason (i.e. it happens when the engine is hot vs cold)? The cranking fuel theory would come into play on a hot motor (and I agree with you that this is probably not likely based solely on 24's).

An ECT out of calibration can cause a similar issue. Remember it's a thermistor if you decide to test it's voltage and/or resistance.

You could see if the bleed screw is run all the way in for some reason. Otherwise, I'd go ahead and clean the IAC anyhow.

I dont like folks to open cans of dog poop but if you ever find the need to hose with the idle, I might set it like I do: I set the hot, no load idle with a zero IAC DC. Ergo I don't need the IAC for the car to idle hot and without a load. This is my preferred method.

Good luck bud.

you hit the nail on the head!!!


i went to ford today and bought a new ford ECT (couldnt find the stock one i replaced with the junk one from autozone) and no more hard starting issues!!!

$40 well spent. starts so much easier and runs so much smoother now


DONT USE CHEAP PARTS STORE ECT SENSORS PEOPLE!!!

 

[stangman94]

to clean your iac dont you have to buy a new gasket?
or can u take it off

 

[HISSIN50]

Urban, nicely done. And thanks for the feedback. It will not only help future searchers but I keep a mental track of the crap I post and what works and what doesn't. I modify my dippy advice as people provide more feedback as to what worked.

 

[urban96]

cheap parts store on the left and OEM on the right

the parts store one was all plastic where as the ford piece was brass with only plastic for the connector

 

[JJ95GTID]

Wow, that's weird.
The one I got from Autozone is exactly like the one on the right with the brass metal.
I guess not all Autozones are alike.

 

[1994Vib.RedGT]

wait.

where does that ECT sensor plug into?

 

[urban96]

the hardlines for the heater. passenger side of the lower intake

 

[Stanger007]

You know that's interesting, because I have a very similar issue. The majority of the time the car starts up without a hitch, but there are these few times where I can let it crank and crank but it won't start unless I floor it.

I know doing that turns off the injector pulse, but I wonder if there is some common link to this?

There's a setting in the EEC for the cranking pulsewidth - with 42s it needs to be dialed back a bit. The cranking and cranking is symptomatic of this setting being untouched or out of calibration - the injectors dump too much fuel in, resulting in a flooded engine.

Could be worth looking into.

Wes