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Aubrey
06-14-2007, 04:02 PM
I have a 2005 Outback with the 5.7 EFI. When the motor is cold, it will not adjust for the cold engine temp and will not stay running when I start it. I have to put it into neutral and warm it up like a carburated engine. After it is warmed up, it starts fine the rest of the day. I do not have a dealer within 10 hours that can put a scanner on it to diagnose the problem and I have already put in a new temp sender and an IAC motor. Has anyone else had this problem ?

thanks
Marlon

Engine Nut
06-14-2007, 07:59 PM
I have a 2005 Outback with the 5.7 EFI. When the motor is cold, it will not adjust for the cold engine temp and will not stay running when I start it. I have to put it into neutral and warm it up like a carburated engine. After it is warmed up, it starts fine the rest of the day. I do not have a dealer within 10 hours that can put a scanner on it to diagnose the problem and I have already put in a new temp sender and an IAC motor. Has anyone else had this problem ?

thanks
Marlon

Your engine has two temp senders. Did you replace the one that has a two wire plug for the connector or the one with a single threaded stud connector. The two wire sensor is for the ECM and the one wire sensor is for the gauge.

Aubrey
06-14-2007, 10:14 PM
I replaced the one with the 2 wire (black & yellow). They are quite inexpensive, so I guess I might as well change the other one too. Thanks for the reply, I was not aware that there were 2.

Marlon

NH Moomba
06-15-2007, 03:56 PM
I don't think changing the one for the gauge is going to help with your starting problems.

Engine Nut
06-15-2007, 05:02 PM
I replaced the one with the 2 wire (black & yellow). They are quite inexpensive, so I guess I might as well change the other one too. Thanks for the reply, I was not aware that there were 2.

Marlon

You changed the right one. That sensor is the one that communicates with the ecm on the engine to tell it what temperature the engine is. When it is cold, the ecm holds the fuel injectors open a little longer to let the engine start better when it is cold. I would sure like to see what temperasture the ecm thinks the engine is. Unfortunately a scan tool is the only way to get that information.

Has it always done this since it was new or is it something that just started this season? When was the last time you changed the spark plugs? I know you replaced the IAC but have you verified that it is operating. Take it out od the throttle body and hold it between the pintle and body of the IAC so the pintle doesn't come out. Have somone turn the ignition switch on then off again after a couple of seconds. You should feel the pintle move (expand and contract) If it doesn't the IAC might not be getting powered properly.

Aubrey
06-15-2007, 07:12 PM
After I posted that last message about changing the guage temp sender, I felt like a bit of a dork when I read it. It has been this way since new (now have 52 hours on it. I'll try to test the iac motor like you said.

Thanks for the input

Marlon

Engine Nut
06-16-2007, 09:02 AM
After I posted that last message about changing the guage temp sender, I felt like a bit of a dork when I read it. It has been this way since new (now have 52 hours on it. I'll try to test the iac motor like you said.

Thanks for the input

Marlon

I PM'd you with some additional questions and info. Hope to hear from you soon.

Aubrey
06-17-2007, 10:47 PM
I READ YOUR MESSAGE THAT YOU PM'D ME, BUT I HAVE NOT YET RECIEVED ANYTHING.

TAYMON@MTS.NET

THANKS
MARLON