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Old 06-15-2009, 11:50 PM   #1
fattie92
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Default 2.5l NA Starting Issues... Idle Surge

Vehicle: 2004 Forester XS (2.5l NA)
Miles: 57k
Owned: Almost 2yrs

My fiancee keeps complaining to me that her car is having a starting issue. She says that she will go to start it, the engine will shoot up to around 2000-3000rpm then it will drop to around 500rpm and almost die, then it will shoot back up to 2000-3000rpm, and then back down. She says Sometime the car dies, sometimes it will correct itself. If it dies, she restarts it with zero issues. She says sometimes it will do it after the car sits over night, and sometimes it will do it after the car sits for a few hours. Then again sometimes it starts right up with no problems.

NO CHECK ENGINE LIGHT

Sounds like a case of idle surge to me. I have done all of the maintenance on this thing since she got it. When she first came to me with the issue I thought right away IACV (idle air control valve).. I went to take it apart and clean it like I have heard of people doing online, but her IACV is completely different then the turbo motor's. Hers is just a simple solenoid style valve. I cleaned it all out anyways and threw it back in but she is still having the same issues. So now I am just thinking about replacing the IACV, but before I blow $250 on the part I want to hear what you all had to say. I don't know the common problems associated with these motors.
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Old 06-16-2009, 02:35 AM   #2
J-Chow
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check out the spark plug, wires, and coil ignition. I had similar problems and I found out that my coil ignition went bad.
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Old 06-16-2009, 08:08 AM   #3
loccomoffo
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maybe its a lose connector to the IACV solenoid somewhere along the way??
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Old 06-16-2009, 08:21 AM   #4
fattie92
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Plugs are newer. Have not replaced the wires or coil pack. This does not really seem like a ignition problem, the car runs great other then these bad starts. I guess anything is possible though.

The only connector for the IACV is at the IACV. Other then that its all in the wiring harness.
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Old 06-16-2009, 06:55 PM   #5
GrundleJuice
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the IACV's are fairly easy/cheap to clean and re-seal. keep that in mind if you can't find other problems. Do you have the ability to log the ECU?
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Old 06-16-2009, 09:15 PM   #6
fattie92
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Quote:
Originally Posted by RaceFaceXC View Post
the IACV's are fairly easy/cheap to clean and re-seal. keep that in mind if you can't find other problems. Do you have the ability to log the ECU?

Its not the same IACV that everyone is taking apart and cleaning. I cleaned it all out anyways, but on this one there really is nothing to clean.

I do have the ability to log it but I can never get it to happen when I try.
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Old 06-17-2009, 07:55 PM   #7
zj4041
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disregard this message
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Old 06-18-2009, 08:38 AM   #8
loccomoffo
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if you're running out of ideas it might be a faulty water temp sensor/connection??
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Old 06-18-2009, 10:01 AM   #9
snoopyone8
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Had the same issue with my wifes 01 LGT, 5MT.

I cleaned the IACV, AND replaced the gasket.

Worked perfect.

These cars should have the same engine/ecu/sensor package as far as I know. Somebody please correct me if im wrong.

-adam

p.s., I just remembered that the surge also started coming back again when her upstream O2 started going bad. Some more food for thought
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Old 06-18-2009, 11:25 PM   #10
fattie92
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Thanks for the info guys. I have no idea what I want to do yet......
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