My roo has an erratic idle from time to time.

I have new plugs wires, pcv, etc.

It is fine 90% of the but occasionally idle will drop below 500 & barley run,sometime even die.

 

Any ideas?

IAC sticking. Try Seafoam down the 1" air tube, let is soak and then start it up. The only other way to clean them is to pull it off the intake.

I had a bad MAF cause some of the symptoms that you are mentioning. Any check engine lights?

is this a legacy or what?

 

idle control are notorious for issues with age/mileage/dirt, though i don't have personal experience with this in legacy's so i'm not familiar with how their idle control is set up. typically they only need cleaned.

Kinda had to assume it was a legacy since it was said to be a 91, or a misplaced Loyale or XT6.

IAC sticking. Try Seafoam down the 1" air tube, let is soak and then start it up. The only other way to clean them is to pull it off the intake.

What tube is this Larry?

is this a legacy or what?

 

idle control are notorious for issues with age/mileage/dirt, though i don't have personal experience with this in legacy's so i'm not familiar with how their idle control is set up. typically they only need cleaned.

 

Sorry forgot I don't have signature anymore.

91 Legacy LS 2.2

1" black hose comes off just after the air cleaner on the bottom of the 3" air duct. It's about 8" long and goes to the IAC on the manifold.

 

Cleaning the MAF with the MAF cleaner would also be a good idea if it has not been done.

1" black hose comes off just after the air cleaner on the bottom of the 3" air duct. It's about 8" long and goes to the IAC on the manifold.

 

Cleaning the MAF with the MAF cleaner would also be a good idea if it has not been done.

Great I will do both, is there actually a MAF cleaner?

I have done it on other cars with carb cleaner.

Anyone have a write up on cleaning the MAF?

Yes, they do sell MAF cleaner at most auto parts stores. If I could not find it, I'd use electrical contact cleaner.

 

Pull the filter box off, if you pull the air tube off you can spray the MAF from both sides. Spray it good and then let it air dry. Put it all back together.

 

Larry

If your 2.2 is hard starting, rough idle, black smoke at start (too rich), you should check the fuel pressure regulator vacuum line. It should be dry, if there is gas in it, the regulator has internal leak and can give these symptoms.