Contour Enthusiasts Group Archives Forums General Troubleshooting Wierd idle

Hi. I have a little problem with my wifes contour.
It is a 97 2.0 zetec with a 95 mystique engine. I had to change the head gasket, because it was overheated. So while everything was opened up, i decided to change the water pump and timing belt at the same time. I managed to put everything back together and now it idles funny.

When the car starts, it runs good for about a minute, then the idle jumps up and then almost stalls out. It does this a couple of times until it finally does stall. The car runs fine if you drive, but when you stop and put it in N or P, then it does the funky idle. I am completly lost. There are no codes popping up and I don't know what it could be. Thanks for any help you guys might have.


Mazdaman

In my experience, my car did this when it had a small vacuum leak in a "come loose" coupling on my intake. Just take a quick check again for any loose-fitting hoses, sometimes they can be real easy to look over. Happens to me once and a while.

Just thought I'd try to help a bit.

Welcome. . In addition, you may also want to try cleaning the IAC valve.

IAC cleaning
from Ray's UIM/LIM how to in Duratec Maintenance how to.

"Replacing the IAC gasket:
(From IAC faq)
Over time, the IAC (Idle Air Control) valve becomes sticky due to buildup from the EGR and PCV systems. It can stick partially open such that idle quality is adversely affected, and engine RPM's will not drop below 1500. For a while, blipping the throttle will restore normal idle, but this only works for so long.

The fix is to remove the IAC valve by unbolting the two 8mm bolts that hold it on and disconnected the wiring plug. If you are careful enough, replacement of the gasket will not be necessary. The gasket costs less than US $1.00, so it is no tragedy if you destroy it. Once the valve is off, spray it out with some carb/intake cleaner and make sure any gunky residue is gone. Reattach, and you are done. It is a lot cheaper than a new IAC, which runs around US $70. Note: Ford claims the IAC cannot be cleaned, but this is not true in my experience." Ray.

Location of the IAC.

"It's on the back side of the intake plenum under the throttle body area." DESIGN.

I looked at the Haynes manual and the Zetec IAC valve is located next to the starter. Below are the steps from the 1996 Ford CD to remove it (assuming it is the same as a 1998).


Idle Air Control (IAC) Valve


Removal

1. Disconnect battery ground cable

2. Remove the air cleaner outlet tube and resonator assembly.
3. Disconnect the main chassis vacuum line.

4. Disconnect the ignition coil and radio interference capacitor wiring.

5. Remove the fuel line bracket retaining bolt.

6. On 2.0L engine equipped vehicles, raise vehicle on hoist.
7.
7. Disconnect the engine control sensor wiring or fuel charging wiring (depending upon application) from the idle air control valve (IAC valve) at the idle air control valve connector.

8. On 2.5L engine equipped vehicles, remove retainer for engine control sensor wiring from the upper retaining stud bolt.

9. Remove the two idle air control valve retaining bolts or stud bolt (depending upon application).

10. Remove the idle air control valve and idle air control valve gasket.


Installation

1. Note: If scraping is necessary, be careful not to damage idle air control valve or intake manifold idle air control valve gasket surfaces or drop material into intake manifold.

Clean idle air control valve gasket mating surfaces.

2. To install idle air control valve, reverse Removal procedure. Tighten the fuel line bracket bolt to 8-12 N-m (71-106 lb-in).

3. On 2.5L engine equipped vehicles, tighten the retaining bolt and stud bolt to 8-12

4. On 2.0L engine equipped vehicles, tighten the idle air control valve retaining bolts to 8-11 N-m (71-97 lb-in).

Thenks for the help. I will try to clean the IAC. It wasn't doing this before I took the engine apart. How could it be messed up now, when it was fine before. If there is anything else, please let me know.

Thanks, Mazdaman

I am at a loss for what could be wrong. I sprayed throttle body cleaner around all hoses and anyhting to do with air. Nothing changes.
I forgot to mention that one of the camshafts snapped in half while putting everything back together. I put another one from a parts engine as a replacement. That one has 62,000 more mile on it.
In the haynes manual it says a worn camshaft could cause a loping or eratic idle. Can anyone confirm that before I burn the car.

Thanks,
Mazdaman

OK, I manged to get my IAC valve out. I ran 12V through it and it clicked, and it opened. How far is it suppose to open. It opened about a 1/4 inch or so. I will try cleaning it, and if that doesn't work, I don't know what else it could be. Will post back in the next day or 2 to let you know what happened.

Mazdaman

Well I cleaned the IAC and put it back in, now the car won't idle at all. Someone please let me know where I went wrong, or you can buy the car for $5.

Mazdaman

Reset the computer (pull fuses 4 and 11 for a few minutes) and then drive it for a while before judgement. Maybe the IAC valve was shot to begin with. Good luck.

when i took out the IAC I tested it and it worked. I also took out the fuses and disconected the battery. Now it won't stay running long enough for me to go for a ride.

Anything else you can think of, I am all ears. I have had enough with this car already. It is the worst car I have ever owned. Nothing but problems..........

Mazdaman