1. Home
  2. Subaru Cars Forum
  3. Losing power on Outback

Losing power on Outback

A problem has developed with our 1996 Legacy Outback, and I'm hoping you folks can help me narrow down the problem before I take it in for service again. The symptoms are that in the morning, when the car is still relatively cold, it will lose power during acceleration (like when getting on the freeway). Sometimes it will be so bad as to stall out, and I'll need to pull over and wait for a couple minutes before starting the engine again. After that, it seems to be ok. Oftentimes, the "check engine" light will come on for a few minutes or hours, then go off again.

This problem started last fall. It happened a few times before the check engine light came on. The first time that happened, I took it to a local repair shop. They put it on the computer and read the code -- misfire on #3 and 4 cylinders. The mechanic did a maintenance tune-up (which included replacing the plug wire set, plugs, fuel filter, oil and filter, fluids, top radiator hose, antifreeze, carb cleaner).

The problem might have gone away for a couple weeks, but it came back. It was time for the 90K mile service anyway, so I took it back to the mechanic a few months later. He read the codes from the check engine light again, and found the same thing -- misfire on #3 and 4 cylinders. He did the 90K servicing, but didn't find anything new about the problem.

The problem continued for awhile, then went away for a couple months. It's been a bit warmer lately, so that may have had something to do with it. This week was a little colder and rainy, and the problem hit again yesterday. It lost power and stalled out, but this time it was while I was decelerating, coming up to a stop light. Otherwise the same symptoms, and the check engine light is on again.

I need to get this fixed! I don't know much about car engines, but I've got the Chilton's manual and I'm fairly handy. I'm hoping someone can either suggest some things I can try on my own to isolate or repair the problem, or else give me some ideas to bring to the repair shop so that I'm not hit with a high troubleshooting bill. Any help is appreciated. Thanks!

Reply to
Dave N
Loading thread data ...

I found an old message

formatting link
*subar u*&rnum=3&hl=en#4172b9107100e7a9) that indicates it might be the alternator going bad. Does that make sense? Is there a way to test the alternator?

Dave N wrote in news:Xns967E6B08CAC8Adavenmailinatorcom@216.196.97.142:

Reply to
Dave N

The only thing I can suggest is looking under the hood at night in the dark while the engine is running. Look for arcing around the coil pack. The car should also be cold when you do this.

I'm guessing that cold and condensation is causing the coil pack to short out until it gets warm.

Just a guess though...

Reply to
Jim Stewart

Thanks, Jim. I'm thinking it's a good guess. I've done a bunch of Google searches in the last couple hours, and apparently this is a common problem. It's always tripping the misfire codes for both #3 and

4 cylinders, and one of the things they have in common is the coil pack (according to a few posts I've found).

So I'd like to try your suggestions. Erm... what is the coil pack, and how can I find it?

Jim Stewart wrote in news: snipped-for-privacy@omsoft.com:

Reply to
Dave N

Hold on, is the coil pack the same thing as the ignition coil? I found that in my manual. Looks like I need to check primary and secondary resistance, and maybe replace it. This could be a cheap and easy fix! Let me know if I'm on the wrong track...

Dave N wrote in news:Xns967E7A3CCFEDBdavenmailinatorcom@216.196.97.142:

Reply to
Dave N

Reply to
Edward Hayes

Here's a picture of my car. The coil pack has the 4 red wires coming out of it. It's called a coil pack because there are 2 coils and each coil is double- ended, with each end going to a plug.

formatting link
As the the resistance check, you can do it, but it may test good and still be bad. Given that your problem goes away when the car is warm, I suspect that it only fails when it is cold and under load.

Still just all speculation, but that's about all you can do at this point.

Reply to
Jim Stewart

Thanks, Jim, I really appreciate your help. Both of these trips to the repair shop cost me $400, and it looks like the coil pack is about $85. That seems like a good suspect, so I'll check and probably replace it. If it might save me the cost of another repair shop bill, it's worth a try. (Of course, now that summer's here, I may not know if that fixed the problem until fall.)

Jim Stewart wrote in news:eJGdnVvHB snipped-for-privacy@omsoft.com:

Reply to
Dave N

Thanks, Edward. I'll follow your suggestions in addition to the coil pack test.

"Edward Hayes" wrote in news:CCEue.1013374 $ snipped-for-privacy@bgtnsc05-news.ops.worldnet.att.net:

Reply to
Dave N

Reply to
Edward Hayes

Or spray it with circuit cooler. The cold and condensation might let you reproduce the failure.

Reply to
Jim Stewart

Dave;

Your problem is rather generic, and I wouldn't put too much faith in the misfire codes. What you really need is a diagnostic check while it's failing. The diagnostic codes may not reflect the actual problem since the ECU is rather simple-minded and only checks for a limited number of faults. The check for high-voltage discharges is quick and easy, but the problem could also be in the ECU or the wiring harness; reseating the connectors on the ECU, coil pack, and any intervening connectors may fix the problem. If it fails again, limp to a dealer if possible and have them check it before it starts to work again.

I had a similar problem with a Toyota that turned out to be the throttle position sensor. The problem was intermittent (stranding me 3 times) and there was nothing to be found after it sat for a while. I took it to a dealer while the problem was happening and they immediately found the bad sensor. I had similar problems with a VW Rabbit years ago, and it turned out to be worn contacts in the ignition switch - fortunately, the switch was much easier to replace than it is on modern cars.

On Thu, 23 Jun 2005 12:31:26 -0500, Dave N wrote: ......

......

Reply to
Alan Ronemus

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.