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Cold start issues anyone?

Old 06-27-2013, 09:58 PM
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Default Cold start issues anyone?

So as I am sure you can tell, I have some issues when starting my stang for the first time of the day. Initially the car revs to about 1400 rpms then works its way down to around 600-700 and will fluctuate. It will go up and down while trying to find its warm idle(800rpm or so) and occasionally die. Because of this I usually have to start the car and immediately start moving to keep the car alive. After the car is driven for around 15 minutes or so it will idle fine, usually wont have issues until the next day.

On a possibly related note the cars rpms will drop when turning the wheel at idle or in neutral.. Occasionally this causes the car to die which can be an issue. I think this may be related to a steering pump going bad? anyone deal with any of this before??

any info and help would be greatly appreciated
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Old 06-27-2013, 10:23 PM
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If you have a pressure sensor in the steering line(i dont remember), then you'll need that and an IAC. If not, probably just an IAC. Maybe even a thorough cleaning of it would work.
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Old 06-28-2013, 07:29 AM
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Originally Posted by mattdel View Post
If you have a pressure sensor in the steering line(i dont remember), then you'll need that and an IAC. If not, probably just an IAC. Maybe even a thorough cleaning of it would work.

I agree , pwr steering pressure switch , yes you have one on the 94/95 Im not sure about foxes , but I would assume they have one as well. This is what tells the ecm how much pressure and load is on the power steering pump so the engine can maintain a set idle. May also throw a temporary check engine light and cause erratic idle and/or stalling.

Clean the iac for sure at least. Also a failing ect sensor can cause problems with idle when cold. Ive seen ect sensors read as low as -40 degrees on a hot summer day, this would cause the ecm to run the engine pig fat rich and Id think youd notice black sooty smoke on a fresh start of the day.
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Old 06-28-2013, 08:52 AM
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Guys if the IAC is bad and or not doing it's job, it'd be smart to resolve said issue because all the powersteering switch is, is a input for the IAC to bump idle, if the output/control circuit = IAC bad, it won't matter what the input is telling the ecm because with a dead output, it can't excecute the input...........also look for vaccum leaks and carbon build up in the TB
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