The Subaru SVX World Network

The Subaru SVX World Network (https://www.subaru-svx.net/forum/index.php)

- Technical Q & A (https://www.subaru-svx.net/forum/forumdisplay.php?f=5)

- - Idle Issue (https://www.subaru-svx.net/forum/showthread.php?t=63201)

Just the other day the idle started to act strange. It seems to idle ok in Park but put it in drive with your foot on the brake or reverse and the idle starts to get uneven dropping low and bouncing back up to normal, when it dips, it dips low enough that I am concerned about stalling. Revving in this state seems to make the engine run a bit rough. When you do start driving it seems ok, maybe slightly rough when you starting out.

I did have some 87 octane gas in it the day before, but have since filled the tank with 93. There are no CEL codes. Ideas?

Both my 92 SVX's have had funny idle, near or actual stall problems with one doing it intermittently and the other finally not starting at all after a stall. Both my problems were fixed with a good MAF swap. I tried the resolder fix on one and didn't help in my case 100% albeit made the stall problem pretty infrequent in comparision to before. Some suggest cleaning...mine were always already clean from regular upkeep with MAF spray cleaner so didn't help. With over 3,000 posts you seen this discussed.

No CEL if MAF the only problem. Get a known good MAF and swap her in...I have yet to not see this fix the problem. In my case, one SVX had the MAF fail at 60K and again at 92K, the other one failed at 90K.

I'm sure some listers here have a decent used one..that's where I got my last one. eBay of course has them but probably a bit more iffy as to quality. A new one can be found on RockAuto for less than the Dealers but still pricey.

http://www.ebay.com/itm/SUBARU-92-97...8e48ea&vxp=mtr

http://www.ebay.com/itm/92-97-Subaru...fff6f7&vxp=mtr

My current maf was resoldered about 3 years ago but maybe it is starting to fail again. I have another one that I can swap in, I'll try it today. I also have a set of coils I can put in but since it druves ok, im not sure it would be them.

Not the MAF, same issue after after replacing it. After driving it a bit more I see that it doesn't matter if it is in park or drive. It still has the too low bouncy idle. Could be time to do the vacuum lines or IAC valve?

Is it worthwhile to swap the coils?:confused:

Here is a video.
http://i644.photobucket.com/albums/u...psm9zi480s.mp4

It was a bad coil. I did the injector unplugging test and found the right front was not firing.

I am very happy that I decided to pick up a spare set off a forum member a while back and was able to fix it right away. I don't remember who it was that sold them, but thank you. :)

Glad to hear the fix...will tuck your problem and solution away for possible good use in the future...

Forgot to ask...any thoughts on why a "misfire" from the bad coil didn't pop a CEL ?

Quote:

Originally Posted by fasteract7 (Post 737827)

Forgot to ask...any thoughts on why a "misfire" from the bad coil didn't pop a CEL ?

I am not sure last time I had a bad coil it was more pronounced and it was throwing codes. When I unplugged the injector there was a very slight change in how the engine was running, where as the other banks made a large change when unplugged. I suspect that maybe it was still functioning in a reduced capacity but I really can't say for sure.

The other unusual thing is that it turned out to be the same coil that I replaced a few years ago, but that replacement coil was used so probably doesn't mean much.

My mechanic calls it a Lazy Coil. I experienced this twice. It's weak enough to notice but not weak enough to throw a code.

Most coil failures I see are from incorrect spark plug application or fouled plugs. Something to check to make sure you don't keep burning up coils.

Good to know, I'll check it out.