06 Legacy GT low idle

**AngelFelix93** · #1: 03-23-2013, 07:44 AM

Hey, I just bought a 2006 legacy GT 5spd with 70k on it. I have owned it for 4 fays now and I am noticing that my rpms are just under 1000 when the cars is running at operating temps. No smoke coming out of wxahust although I did noticed it flutters when stopped. This is my first subbie so I could use some helpful tips and guidance as to what I should do?

**wurkenman** · #2: 03-23-2013, 08:43 AM

Welcome, but no help from me.

**shadowsports** · #3: 03-23-2013, 09:40 AM

Just under 1k when warm is high. Mine sits at 750rpm. a small amount of ocassional fluttering is also normal... note ocassional.

You haven't said if the car has been modded besides exhaust. Do you know if the car is running a stock map? ... Welcome

**PeterJMC** · #4: 03-23-2013, 12:46 PM

Welcome to the site! Not sure where you might want to start with that to troubleshoot but I would assume that an off idle would likely be caused by air entering into the intake system unmetered.

You might first want to check all the vacuum lines for leaks and also check the TMIC to make sure the end tanks are not separating from the intercooler. Then you might want to check all the intake piping and make sure pipes are properly attached to each other.

**AngelFelix93** · #5: 03-24-2013, 07:19 AM

No mods stock exhaust and maps.

I am also noticing that I had oil splattering up the side of my car so I went ahead and check the motor oil and that was okay but my diff oil was bone dry i checked the underneath of the car to see if I could see any wet spot but I couldnt see anything so I went ahead and filled it with castrol 75x90 im starting to think this car wasnt really worth the buy

**shadowsports** · #6: 03-24-2013, 08:22 AM

Low diff oil shouldn't affect your idle. Before you start troubleshooting, you should probably give the car a once over. Check fluid levels, check the air filter, replace if dirty. Then start checking your plumbing as Peter suggests, end tanks for separation, etc. While your topic states low idle, your description is actually faster than normal.

Finding leaks in hoses can be tricky. Hose might look fine, but can have a small crack or split on a nipple or fitting. The issue may not be serious enough to register a CEL but may be causing the idle problem. Start by giving the car and engine bay a once over.

**scoobyscoodle** · #7: 03-25-2013, 11:59 AM

Welcome!

**Alex-->TheGreek** · #8: 03-28-2013, 12:21 PM

Welcome to the forum!

A friend's Legacy had problems with unstable idle(unusually low), couldn't find the problem for a long time, eventually though he got a CEL caused by a faulty O2 sensor. We changed the O2 sensor and now the idle is butter smooth!

Meaning of the story is, even if you've got no CEL a bad O2 sensor can mess your idle.

**311logan311** · #9: 03-28-2013, 01:25 PM

Your car's stock map has a target of 750rpm's once warmed up (158-176 degree area and above). that is normal. Clean your MAF sensor, use some lucus fuel injector cleaner and make sure your airfilter is clean. Your car should idle a bit smoother after that. Your car sounds fine.