I could not for the life of me remember. I have an image in my head of a seal but don't remember what it's from (Ford, Chevy, GM, other). 
Fox 1993 FOX High Idle
- Thread starter TheJay806
- Start date
- Mar 2, 2015
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The egr usually wisps a little smoke at that orange seal duri g a smoke test. Not saying it isn't bad. The most common area for a vacuum leak is the hose that runs under the intake behind the distributor. That hose is hard to see and to get to. ( should be seen in a smoke test.
I seem to remember an o ring type seal under the factory tps. Its been a very lo g timesince I've seen one though. I know my aftermarket one doesn't have one on it...and hasn't for many years. A very small amount of snoke is acceptible from the throttle shaft wnen smoke testing.
I seem to remember an o ring type seal under the factory tps. Its been a very lo g timesince I've seen one though. I know my aftermarket one doesn't have one on it...and hasn't for many years. A very small amount of snoke is acceptible from the throttle shaft wnen smoke testing.
Replaced the EGR valve and boom, idle immediately dropped down to normal. Problem solved. Thanks everyone. I did a smoke test one more time to double check and no leaks.
Any idea what size this hole is? Could i put a lock screw and bolt in here or is it to dangerous?But stock TBs have the hole present, so hard to say if he’s looking at someone’s band-aid fix, or just a stock TB blade with a hole present.
Stoxk hole here
Can I block or lock nut and bolt this hole? Or is it to risky and better off getting a new throttle body?But stock TBs have the hole present, so hard to say if he’s looking at someone’s band-aid fix, or just a stock TB blade with a hole present.
Stoxk hole here
There is nothing you need to do with that hole IMO. It's there from the Factree. 
The hole is not the issue. It’s supposed to be there. Blocking it may actually cause the throttle to stick slightly.
If you want to test it to see if it’s the cause of your issue, stick a nice peice of duct tape firmly across it. If the idle is still high your problem is still elsewhere
If you want to test it to see if it’s the cause of your issue, stick a nice peice of duct tape firmly across it. If the idle is still high your problem is still elsewhere
I followed these instructions for resetting the idle etc. it worked like a charm. On start up it now idles at 750. After driving for a bit it moves back to 1000rpm. If I shut it off and start up a little later, back to 1000rpm. Is this normal? Or would this be a faulty IAC? I have a new IAC I can throw on and do the procedure again if need be?
"
Clear the computer's idle memory by disconnecting the battery for 20+ minutes.
-Disconnect the Idle Air Bypass solenoid (IAC)
-Reconnect battery
-Start engine and set idle speed to desired RPM with idle screw on throttle body
-Turn off engine and reconnect the air bypass solenoid
-Set TPS voltage between 0.90 - 0.95 volts with a digital volt meter
-Start engine and let it idle for 2 minutes with no accessories on.
-Turn off engine for two minutes
-Start engine again and run for 2 minutes with every accessory turned on.
-Turn engine off again.
"
"
Clear the computer's idle memory by disconnecting the battery for 20+ minutes.
-Disconnect the Idle Air Bypass solenoid (IAC)
-Reconnect battery
-Start engine and set idle speed to desired RPM with idle screw on throttle body
-Turn off engine and reconnect the air bypass solenoid
-Set TPS voltage between 0.90 - 0.95 volts with a digital volt meter
-Start engine and let it idle for 2 minutes with no accessories on.
-Turn off engine for two minutes
-Start engine again and run for 2 minutes with every accessory turned on.
-Turn engine off again.
"
The steps you did were pretty good, but you missed a key one near the beginning.
When you disconnect the IAC, you need to disconnect the SPOUT connector on the distributor as well. If you don't, the PCM will keep adjusting the timing to improve idle while you are making adjustments and you will be chasing your tail trying to get it lower.
Also, when you set the idle, set it as low as it will still keep running - it will not likely run smooth but it just needs to keep running. I have gotten the idle down in the 550 - 650 rpm range on this step. The lower you can get it, the more range the IAC has to work with to maintain idle when you are done with the process.
The rest of the steps you did looks good.
When you disconnect the IAC, you need to disconnect the SPOUT connector on the distributor as well. If you don't, the PCM will keep adjusting the timing to improve idle while you are making adjustments and you will be chasing your tail trying to get it lower.
Also, when you set the idle, set it as low as it will still keep running - it will not likely run smooth but it just needs to keep running. I have gotten the idle down in the 550 - 650 rpm range on this step. The lower you can get it, the more range the IAC has to work with to maintain idle when you are done with the process.
The rest of the steps you did looks good.
So the only way I could get it to work is by starting the car with the IAC already disconnected, can I do the same with the spout?
I'll try again tonight, but typically before, If I unplugged the IAC while the engine was running it did nothing. No change. That was before actually getting the idle lower though. I've smoke tested and no vac leaks, EGR was leaking previously, I replaced it. EGR is installed and connected but hoses are capped off.
But, if i let it sit for while, and go back and restart it, it'll idle perfect again. It just seems like once I start driving, on the hwy especially, then the idles stays at 1000
can you provide additional info on the car? There are a few other things that would cause this depending on a few things.
What year is this car? Original mass air car? Have you dumped codes? Do you know if your VSS is hooked up? Is this an AOD-to-T5 swap car?
There are some electrical gremlins with swap cars with mismatched ECUs and stuff that can also cause idle hang.
What year is this car? Original mass air car? Have you dumped codes? Do you know if your VSS is hooked up? Is this an AOD-to-T5 swap car?
There are some electrical gremlins with swap cars with mismatched ECUs and stuff that can also cause idle hang.
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