Why does my car start/stall unless I am giving it gas after I changed my manifold?

Tiny
MUSTANG_FREEQ
  • 1997 FORD MUSTANG
  • 200,000 MILES

I have just replaced my intake manifold on my '97 Mustang & I now have the following symptoms:
Low Idle
Start/Stall
Temp Gauge now working
Overheating
A/c not working
What am I supposed to do? I read none forum that said I could have a pinched wire; but I do not see how or where this could happen. I have the free hanging plenum & no wires run through the manifold area itself. Any help would be greatly appreciated. All I wanna do is get her back on the road properly.

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Saturday, June 16th, 2012 AT 1:44 PM

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Tiny
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Check for vacuum leakages for the low idling.
As to the A/C etc not working and overheating, have you checked the fuses?
Did you miss out any ground circuit connections?

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Saturday, June 16th, 2012 AT 1:48 PM
Tiny
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I am not sure; someone told me it could be a pinched wire; but I am not sure where I coulda done that

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Saturday, June 16th, 2012 AT 1:56 PM
Tiny
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I know I hooked everything back up as it came off. Other than that I am not sure as to the grounds if they are hooked up or not; but I would suppose so. The thing is that everything worked fine before I changed the manifold. The only thing I did that wasn't by the manual was disconnect the battery.

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Saturday, June 16th, 2012 AT 2:02 PM
Tiny
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Ground circuits are bolted to some part of the engine so if any was disconnected while removing bolts, they could have been missed out.

As to the overheating and A/C not working, it could be a blown fuse so did you check as I suggested? Sometimes jumping the gun makes you go round in circles. Always start with the basic. A blown fuse would prevent the cooling fans from working and this would result in overheating and tha A/C not working. Btw recheck the wiring connectors that you disconnected. Check if any had been interchanged. Note the wire colors.

You mentioned disconnecting the battery. That can result in low idling as computer memory is erased and needs to relearn. During this time the idling would not be stable and might stall. One way of expediting it is to get the throttle body cleaned to eliminate air flow restriction due to dirt accumulating.

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Saturday, June 16th, 2012 AT 2:23 PM
Tiny
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I understand what you're saying; but I have hooked all things up & like I said the only thing I DID NOT DO was unhook the battery. But like I said before, I was told it could a pinched wire causing all these problems. I am just trying to figure out where I could've pinched a wire under or around the manifold. That's what I really need help with; because if that's not the problem than it is going to Pep Boys to get fixed.(For no less than $200.00)

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Saturday, June 16th, 2012 AT 2:52 PM
Tiny
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And it not Temp gauge now working; it is Temp Gauge not working. Daggum big fingers & bad eyesight.

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Saturday, June 16th, 2012 AT 2:53 PM
Tiny
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Lol. I read it as the battery was disconnected. For the temp gauge not working, I understood it as a typo and understand the situation.

Have you checked the fuses?

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Saturday, June 16th, 2012 AT 2:57 PM
Tiny
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Here's the thing, everything was fine until I changed the manifold; which had to be done.

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Saturday, June 16th, 2012 AT 3:30 PM
Tiny
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Let us start with the basics. Temperature gauge first. The attached schematic shows the temperature sending unit wiring. Unplug the connector and use a wire to ground the Red/White wire. Turn ignition switch on and if the gauge works, either the switch or ground circuit is bad. If gauge works, do not keep ignition switch turned on for more than 3 seconds.

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Saturday, June 16th, 2012 AT 3:31 PM
Tiny
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Why don't you want to answer my question?
If you do not want to answer, I would not be able to help you.

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Saturday, June 16th, 2012 AT 3:35 PM
Tiny
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No, I have not checked the fuses because they were fine before I changed the manifold. I have also changed the thermostat & the heating sensor & the coolant temp sensor thinking those may be the issues. You're really not answering my question either. Is there any way I could've pinched a wire in or under the manifold? I am not seeing where this could happen; but I have had two mechanics tell me that they think this is my problem

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Saturday, June 16th, 2012 AT 3:48 PM
Tiny
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I do wanna thank you for your help; but is there the possibility of a pinched wire? That was my basic question which still has not been answered.

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Saturday, June 16th, 2012 AT 3:58 PM
Tiny
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I keep asking if you have checked the fuses. If there are any pinched wires, the fuse would blow or the temp gauge would shoot to maximum.

Without knowing the problem how would you expect me to answer you. You mentioned there were no witres around so how can you have a pinched wire? You did not ask me if it is possible, You kept saying others have told you so. If you don't want to do it my way, the you would have to get somebody else to do the job.

Have a nice day.

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Saturday, June 16th, 2012 AT 4:10 PM
Tiny
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I just want to know what the deal is. As far as the temp gauge I said it is not working which is causing the car to overheat. I also have to manually idle the car. But again I say that these problems were not until after I changed the manifold. I am not a dumby. I do (for the most part) know what I am doing. So again, what could have caused all these problems at the same time?
1)Very low idle (300 - 500 rpms); when it idles
2)A/c Stopped working
3)Coolant Temp Gauge stopped working
4)Start & Stall (unless I punch the gas)

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Saturday, June 16th, 2012 AT 6:07 PM
Tiny
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A blown fuse can cause all these and you refuse to start with the basic.

Sorry to say I am not able to assist you further.

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Saturday, June 16th, 2012 AT 6:25 PM
Tiny
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All we're trying to do here is help people in need of car repairs being uncooperative will not help here, reading it all I suggest you go somewhere else and seek help-You came here for a reason-

FYI, disconnecting the battery is a bad idea-there's a way to keep the computer memory alive at all times-Do you know this?

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Saturday, June 16th, 2012 AT 6:47 PM
Tiny
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Hi Jess, welcome aboard.

Lol. Thought I was the one who read the question wrong. Seems you too read it wrong. The battery was not disconnected.

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Saturday, June 16th, 2012 AT 7:05 PM
Tiny
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What's this? The only thing I did that wasn't by the manual was disconnect the battery.

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Saturday, June 16th, 2012 AT 7:27 PM
Tiny
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Thank you; but all I was asking in the first place was if there was a way I could've pinched a wire in the process of doing this; it turned into somewhat of an argument. So, when changing the manifold lower manifold on a '97 Mustang is it possible to have pinched a wire even though I have the free hanging plenum, & I see no possible way for it to happen? If so, please explain how. The reason I ask this specifically is because IO have two mechanics tell me this is what it could be; as well as a Mustang forum.

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Saturday, June 16th, 2012 AT 7:46 PM
Tiny
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And it says the only thing I DIDN"T do by the manual was disconnect the battery

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Saturday, June 16th, 2012 AT 7:47 PM

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