Hi all, I apologise for any misuse of terms and such for I am not familiar....but here goes.

I have an automatic 05 Legacy/Outback. I noticed super slow idling when stopped, or coming to or starting from stop. Of course it is worse when a/c is on but I'm sure thats a given. I took it to the dealership and they read the computer, no codes and cleaned the trottle, seemed to work slightly for a day or so, now the problem is back. Then took to a smaller sube specialty shop and they said my car has a california issued computer/system and there computer cannot read those coded. Took back to the Subaru dealership and they said if it was California issued they would of know when they plugged in the computer, I pointed out the sticker on the hood to them that said it was, then they changed there story to, well our computer can read any subarus computer no matter where it is from. So, no one knows what the problem is, my question is is this normal, cause I'm afraid its just gonna stall out on me one day, and does it have to do anything with the CA issued system? Maybe they idle slower? Who knows, any suggestions anyone? Thanks!!

Hi mountngrl80, welcome aboard.

 

I think you're getting a massive runaround! Somebody correct me if I'm wrong, but any OBD2 scanner should read your codes--the "CA system" comments don't make any sense.

 

I'm not familiar with '05 models or automatics so hopefully someone else will jump in here. Could it be a speed sensor (VSS)?

 

Only other thing I can think of is to try the "search" function (up above) and see if you can find any discussions of similar problems.

 

Good luck and keep asking questions.

Ooops, sorry--I should have asked for more basic informnation!

 

How many miles on the car? When/how did the slow idle start, was it gradual or sudden? Have you had a tuneup recently? How about preventive maintenance, filters/fluids?

Well, it has about 70,000miles, I just purchases the car about 3 weeks ago and started noticing the problem about week after having it. It seems to be happening gradually. The Subaru dealership did one of those so many point inspections and came up with nothing and I haven't tried and preventive mainenance or tune ups..would probably be a good idea though...I tried the search function and haven't came up with anything similar yet. Thank, and you're right, I feel I'm getting the run-around also.

I have an automatic 05 Legacy/Outback. I noticed super slow idling when stopped, or coming to or starting from stop.

Just how slow is ''super slow''? They normally idle around 700 RPM. The first mark above zero on the tachometer is at 500 rpm, with each small increment being 100 RPM, so 700 RPM would be 2 increments above the one for 500.

 

 

Of course it is worse when a/c is on but I'm sure thats a given.

Actually, that's not a given. The engine management system should detect the additional load of the A/C and compensate for it.

 

I have some ideas, but knowing the idle RPM and answers to the following questions would help direct a diagnosis.

Is the idle smooth or rough?

If you're in a mountainous area, what's the elevation?

Well, it is idling about 1/3 up from the zero and 2/3 below the 1..so I would guess 600 RPM (mine doesn't have lines between the numbers so it's hard to tell). It is still a smooth idle though, so quiet I think it has quit on me sometimes. And the area I live in is mountainous in about the 2600ft. area. Thanks, any advice is greatly appreciated.

Edited August 25, 200916 yr by mountngrl80

Here's a link to a picture of one style of Subaru tach: http://www.lovehorsepower.com/images/Subaru/tach.jpg.

It doesn't have the smaller increments, but like those that do, the first mark after that for the zero would indicate 500 RPM -- the remaining increments are of 250 RPM. Therefore the next (not as heavy) mark would be 750 RPM, and the ''1'' would of course be 1000. While 600 RPM is slightly lower than typical for idle, it isn't too far off. However, if what you're describing is close to the 500 mark (about 1/3 of the way to the ''1''), that would be somewhat lower than expected.

 

Being a half-mile high will affect operation to some degree. Simple things like a dirty air filter should be checked for if not already done. Taking an intake vacuum reading could help to determine what's happening.

dirty IAC?

 

in my impreza I had a small vacuum leak and with the AC on it could cause it to stall at the right moment (Auto) but the funnest thing happened one day in the park the AC kicked in and the idle jumped down to 500 then back up it did almost stall.

Thanks for the pic, I would say at start up it idles around 650, but after sitting a minute, or if put in D or R it slows down to about 550...The a/c had to be recharged at the dealership before I bought it and it still doesn't seem to be super cold at times...don't know if that goes along with the vacuum reading or dirty IAC (by the way..what does that stand for)? Not sure if the air filter has been checked or not, I will check it out and get back to ya...thanks!!

IF the idle is smooth and it hasn't stalled I wouldn't worry. The idle spec is 700 +/- 100......so you are right on the edge of normal.

 

If it actually stalls.....or has a surging up and down to the idle then there is an issue.

 

Otherwise I wouldn't suggest anything except maybe change the plugs, wires, and fuel filter.

 

Don't buy the plugs from the dealer....you'll get hosed.....you can buy the same NGK or DENSO plugs from an auto parts store for a 1/4 of the price. Make sure to get NGK or DENSO. Get NGK wires for it as well.

Is your check engine light on? I would also say any code reader would be able to read the codes regardless of Cal vehicle or not.

 

+1 on tune up. filters, plugs, plug wires.

 

If the check engine light is on go to your autoparts store and see if they'll read the codes for you.

 

Good luck.

 

Daniel

The IAC or IACV is the Idle Air Control Valve--it meters the amount of air to keep the engine idling when the throttle is closed. I'm a big proponent of removing and cleaning them, especially when an engine is pushing 80 or 90k miles. But, as was pointed out, if your idle is smooth and you're not stalling out it's probably not necessary yet.

 

If you don't know much about the car's history it would be good to do the basics--plugs/wires, air & fuel filters, new PCV valve, etc.

 

Some parts should be genuine OEM Subaru--these can often be bought online at better prices than dealerships. Some parts are fine from auto supply stores. Keep asking questions here and we'll try to steer you in the right direction.

 

Good luck!

No, the check ingine light isn't on...Thanks all for the input, I will go ahead replace the parts suggested and will be back if anything else good or bad happens.

Ok all...I checked the spark plugs..wires, fuel filter and air filter and they are all new. Ive noticed that the idling does jump down when the fan kickes on and jumps back up when it turns off like it's draining the power..could it be a bad alternator?