EJ 22 97 OBS surging on start up

[Skorzen]

I just noticed yesterday that after sitting overnight when I start my car (97 OBS EJ 22 5 Speed 78K mi) the engin revs higher than normal for a cold engine, and the settles down to where it would normally be. this morning it went to 2.5K and then settled down rather than the normal 1.5 or so that I normally see when I start it cold. So I am wondering if anyone has any idea why it's doing this? It bothers me that this just started, but it also seems somewhat minor, but I would like to know why it's doing this just in case it's not minor. Oh and another note: timing belt, cam and crank seals, oil pump reseal and water pump were all down about 3000 miles ago.

 

Thanks

 

-Will

[idosubaru]

throttle body sticking open maybe? then loosening as it warms? i doubt it, but i've seen sticking TB cause high idle before. should be able to tell, when it does it just check the TB by hand and make sure it's closed all the way.

 

some (many) vehicles by design will rev high on a cold engine. once the engine reaches operating temperature the idle smooths out to nominal rpm. the engine is designed for and most efficient at a prescribed temperature so that's why they do that. that yours if variable could be an issue with the idle control valve...not sure how the EJ22 does that though as i have never had to deal with that yet. if there's a valve involved (IAC - idle air control valve) then typically just cleaning it out will alleviate the issues. they get black soot in them and they tend to stick open or not operate smoothly.

[porcupine73]

After it's been running for maybe 20 seconds, if you tap the throttle lightly a couple times does that bring the idle down at all?

[jcniest5]

Sounds like it's an IAC problem. Search on this forum for IAC threads/posts and find out where it's located on your engine. Replace it will fix this problem.

[tiredandwired]

I've attempted to search IAC, but nothing comes up. What is this? I have similar surge at start up too and recently #3 cylinder misfire code that can't be duplicated...yet.

 

Sounds like it's an IAC problem. Search on this forum for IAC threads/posts and find out where it's located on your engine. Replace it will fix this problem.

[porcupine73]

Hi tiredandwired and :welcome: ! IACV is idle air control valve. A pic of roughly where it is on my '96 is below. Vacuum leaks can also cause high idling. For cylinder misfire, what condition are the plug wires in and are the OEM? How about the spark plugs? Are they NGK or other Japanese type?

[OB99W]

I've attempted to search IAC, but nothing comes up.[...]

The search function doesn't like things that are only three characters long. Try "iac*" (without the quotes).

[tiredandwired]

Hi-

 

Thanks for the reply. I bought the car used a couple of years ago from a guy who maintained it well, though didn't save any records. The mechanic said the plugs were worn but not excessively and that they were platinum. The HG was done at 150,000, hte car has 193,000 presently. A couple of other posts I read suggested it may be the coil.

 

Should I wait until it gets worse or start doing the obvious now?

 

Any advice greatly appreciated~

 

Maggie

 

 

 

The search function doesn't like things that are only three characters long. Try "iac*" (without the quotes).

[porcupine73]

If your plug wires are not OEM or are more than a couple years old, the first thing I'd try for misfire is to replace them with new OEM wires. Maybe if plugs aren't relatively new put in new NGK plugs (not champion or autolite or anything like that).