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  #1  
Old 01-02-2007, 08:00 PM
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Default Idle Problem

I've got a 2000 GT and am having some problems with it. I know i need an oil sending unit, but don't know if that's my only problem. Randy told me about the oil sending unit a few weeks ago, but i was out of town and haven't changed it yet.
Got back in town yesterday and my stang starts up, but then turns off because it is idleing too low. I don't know what's causing this. Stays on when i rev it up to about 600 RPM, but i've never had to do this before.
Could the bad oil sending unit be causing this, the only symptom this showed before was the oil pressure reading zero until the car warmed up?
Any ideas would be greatly appreciated?
 
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Old 01-02-2007, 09:15 PM
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vacuum leak or bad IAC. Start by cleaning out the IAC. It's on the front of the upper plenum.
 
  #3  
Old 01-02-2007, 10:42 PM
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vaccum leak.....somewhere
 
  #4  
Old 01-03-2007, 09:55 AM
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What mods do you have? How quickly does it turn off? I mean does it shut right off?
 
  #5  
Old 01-03-2007, 10:02 AM
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The only mods i've got are a fenderwell MAC cold air intake and Steeda Tri-ax. I changed the air filter on the cold air intake out a few weeks ago. I replaced the MAC one with a K&N one. Could this be the source of the vacuum leak if that's my problem?
 
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Old 01-03-2007, 12:27 PM
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Originally Posted by r3dn3ck
vacuum leak or bad IAC. Start by cleaning out the IAC. It's on the front of the upper plenum.
I'd go with the iac (idle air contraol valve) like redneck said, is it giving any codes?
 
  #7  
Old 01-03-2007, 12:57 PM
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Got home from work and found the problem, but haven't figured out what's causing it. I took off the new K&N air filter off my fenderwell MAC cold air intake. The car started and idled just like it's suppossed to. But when i put the K&N air filter back on, the car starts to bog down again like it's not getting enough air.
What gives, the K&N air filter is exactly the same as the MAC one i replaced. Car worked fine for 5 years with the MAC filter, but doesn't now with the K&N one. Is there something special about the K&N one?
Any suggestions?
 
  #8  
Old 01-03-2007, 12:59 PM
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MAF could also be all oily from the new air filter. one of the boys should have a good aerosol method for cleaning the MAF element. Between that and the IAC. Vacuum problems would kick a code if it was severe enough for the engine to die.
 
  #9  
Old 01-03-2007, 01:14 PM
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If the MAF or IAC was the problem, wouldn't the problem still be there when i take off the air filter? The car works fine when i take the air filter off, but i can't drive around like that.
 
  #10  
Old 01-03-2007, 02:16 PM
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sounds like the K&N is choking it out, is it correctly oiled, nothing inside the filter like a rag or something. Maybe give the K&N a good cleaning.
 
  #11  
Old 01-03-2007, 02:42 PM
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Nope, nothing inside the air filter, checked that earlier. I just finished taking off the filter and let the car run for about 15 minutes while parked. Someone mentioned earlier that the air filter oil may have affected the MAF. I'm hoping let it run without the filter would dry it out.
I put the filter back on and it seems to be working, but the check engine light is still on. If i remember right, it should clear itself out when it no longer detects a problem.
I don't have a code scanner, but i'm looking up the procedure for checking it out by holding in the trip meter for a few seconds while turning the key to accessory. Maybe something will show up.
 
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Old 01-03-2007, 03:16 PM
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to clear the code disconnect the battery for 10 minutes. restart and go from there. Note that once you've done the disconnect thing the adaptive tuning will probably be in learn mode again and you might see some drivability issues for a little bit. Maybe...

hope it stays running right for you. those kinds of issues are a PITA.
 
  #13  
Old 01-03-2007, 03:18 PM
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The check engine light cleared, so i couldn't check what code caused it. The car seems to be running fine now.
Doesn't make alot of sense though. All i did was take off the air filter, let it run for about 15 minutes and put the filter back on. Drove around a little and seems fine. Weird!!!
Thanks for the help.
 
  #14  
Old 01-03-2007, 03:20 PM
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That's why I always say there's no such thing as a bolt on. It's never that simple.

Call it fixed and wait for a code. I'd pick up a Xcal-2 or something similar so you can see the codes, reset them and fix the causes when needed. It'll pay for itself if you use it twice to check/clear codes.
 
  #15  
Old 01-03-2007, 03:23 PM
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The X-Cal sounds like a good thing to add to my income tax refund wish list. Thanks.
 
  #16  
Old 01-03-2007, 03:56 PM
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as far as checking and clearing codes..... Autozone will read it for free in the parking lot..... And to clear it... just pull a fuse under the hood for a min.
 
  #17  
Old 01-04-2007, 10:44 AM
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Originally Posted by ericgutz
I've got a 2000 GT and am having some problems with it. I know i need an oil sending unit, but don't know if that's my only problem. Randy told me about the oil sending unit a few weeks ago, but i was out of town and haven't changed it yet.
Got back in town yesterday and my stang starts up, but then turns off because it is idleing too low. I don't know what's causing this. Stays on when i rev it up to about 600 RPM, but i've never had to do this before.
Could the bad oil sending unit be causing this, the only symptom this showed before was the oil pressure reading zero until the car warmed up?
Any ideas would be greatly appreciated?
I had that same problem and replaced IAC valve.. problems
 
  #18  
Old 01-04-2007, 10:58 AM
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I'd try cleaning the K&N and then taking off your IAC. Clean it with carb cleaner, and than spray some into the plenum. Also spray a little little bit into the vacuum line.

This is cheap and doesn't require replacing anything yet. chancer are this will help drastically. If not, then go for replacement parts if you can diagnose the problem.
 
  #19  
Old 01-04-2007, 01:22 PM
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Car seems to be running fine now, but cleaning out the IAC sounds like a good idea to do anyway. Where is it?
 
  #20  
Old 01-04-2007, 01:47 PM
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front of the upper intake plenum. There's a hose to it from the intake snorkel. Disconnet electronics, remove IAC, shoot cleaner through.

Other than the TB it has the only wires on the front side of the upper plenum.
 
  #21  
Old 01-05-2007, 12:49 PM
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I think i'm gonna pass on the IAC. The hose feels like i'll tear it if i pull any harder. Car seems to be running fine now after messing with the air filter. Thanks anyway.
 
  #22  
Old 01-05-2007, 04:19 PM
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How do you know your oil sending is bad? I may be having problems with mine and I am curious as to what you are seeing.
 
  #23  
Old 01-05-2007, 04:35 PM
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Originally Posted by ericgutz
I think i'm gonna pass on the IAC. The hose feels like i'll tear it if i pull any harder. Car seems to be running fine now after messing with the air filter. Thanks anyway.
Yea, it's a doozy trying to get off. It's still a good idea to try, maybe spray a little of that carb cleaner around it for some slight lubrication.
 
  #24  
Old 01-05-2007, 05:42 PM
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Originally Posted by WaterDR
How do you know your oil sending is bad? I may be having problems with mine and I am curious as to what you are seeing.
The oil pressure gauge would stay over to the left when i started the car and would jump up to normal after the car warmed up for about 5 minutes or so.
 
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