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Someone PLEASE help me...I'm running out of ideas!

Car: 1995 Ford Contour Engine: 2.5L Duratec Miles: 102,000

This car is driving me to drink!!!!

You start the car, it revs to 2500, tries to come down to regular RPMs(below 1000), and then dies. If you play with the gas pedal, you CAN get it to stay idling, but it's VERY shaky and does not sound good at all.

At first, I thought it was an EGR problem because I had one before with similar symptoms. But I tested the valve with a Vacuum Pump and it worked perfectly.

Then, I noticed that the car would not stall and die if I disconnected the IAC's air supply hose that comes off of the main air intake system. Of course it would idle at about 1300, probably beacuse of the New vacuum leak, but it would not die in Park or Drive. I also found that as SOON as I hooked that IAC air supply hose back-up, the engine immediately would stall. And I MEAN immediately!!

So, knowing this, I assumed it was the IAC valve not responding to allow more air into the engine. I went and got a New one, installed it, and it made NO difference at all!! This really got me mad!!

Then I decided to keep starting the car and REALLY listen closely to hear what was going on.

I first noticed that every 20 seconds or so, I could hear this wierd "popping" sound. It was pretty startling. Maybe a really bad lean mis-fire. I then got in close to where the plug wires connect to the coil and I could hear a pretty loud "ticking" sound. With the engine running(barely), I disconnected one of the plug wires from the coil, and to my surprise, it made NO difference at all!! I also noticed that the spark itself was not the light blue color that I am used to with my 3.1L Cutlass Supreme...it was more of an orange color, which may indicate a weaker or less hot spark...which may just be normal for this engine/car??

Anyways, right now I have all the plugs and wires removed because I'm going to replace them all anyways...they pretty much look like the originals!!!(this is my sisters car)

I've measured the resistance of the ignition coil, and I'm getting 1.8 ohms, which is 3 times higher than the specified 0.45-0.55 ohms. I'm not sure how much of a difference this will really make though?

One other thing that I'm weary of is the IAC's supply voltage. Ford states that the VPWR should be 3.5-11.0 volts at 3000 RPMs. Well, when I test it with my Multi-Meter, the voltage is ALWAYS 14.5, or whatever battery voltage is at the time of measurement. I assumed that the voltage would be variable based on what the PCM wants the idle to be at??

Anyone?

Reply to
bigbossfan80
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This may sound silly, but one day you woke up and started the car and you suddenly had this problem? Did you do any work to the car just prior to the problem starting to happen? If so, then you will need to go back to the work you did and check it to make sure it is right.

Fwed

Reply to
fweddybear

Hi, Any manifold vacuum leak(s)? Checked PCV? In cold weather engine needs warm air not frosty cold air. Tony

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Reply to
Tony Hwang

I once had a car do screwy things like that idle thing and having to play with the throttle to keep it running. My problem was MAP sensor. No check engine light but the meter showed it bad. Replaced sensor and all was back to normal.

Dan

Reply to
Lewis11561

Until you started talking about popping sounds and orange sparks, this sounded like a possible TPS problem. I have had two separate TPS problems on two separate cars. One of them was the TPS completely died, the other is that the vacuum hose connecting the TPS to the engine air outtake system was wripped in half.

On the car where the TPS died: As the TPS was dying, the car became progressively worse ... to the point where I could not start it anymore.

On the car where the vacuum hose broke: it always ran, but not smoothly on acceleration and when I pressed the gas, the car hesitated and, sometimes, died.

Could it be that when you remove a vacuum hose, the TPS voltage output is simply ignored by the computer, but when you reconnect, the TPS voltage output is erratic and causes the car to respond and die? Or something along these lines? Perhaps it could be two problems ... the orange spark problem I do not know, but the hitting the gas and getting hesitation problem really sounds like the TPS ... exactly my symptoms both times.

Reply to
Kevin Stern

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