Whole car shakes at low RPM

Hey all,

 

I just bought a 2005 Legacy 2.5i with just over 100k miles. It's in great shape, you can tell the PO really took good care of it. My only concern is at lower speeds, when the clutch is pushed in and the revs drop (to the lowest notch on the tach) the car shakes. It will usually bounce up to about 800, and the shakes go away. But if it bounces back down, car shakes again. I've never owned a boxer, so something tells me it could just be the engine geometry at low RPM. It doesn't ever die. (I should say, once I started it and it died before the RPM could bounce back)

 

My first thought was it could be a dirty air filter. I threw a new one in and it's still the same. Other thoughts could be MAF or partially clogged fuel filter. It should also be noted, the lights dim as the revs drop to the shaking zone. Any thoughts would be greatly appreciated.

 

P.S. I checked the charging system and battery, both are fine.

I forgot to mention, but it’s probably somewhat pertinent. I live in Green Bay, WI and the temps have been between 20-35.

No this isn't a mechanical issues this is a ECU problem happened and happens to many of us 2.5i owners with the 5MT. You are driving normally, you get to a stop light, press in the clutch and it drops to about 650 RPMs, shudders, then climbs back to normal idle.

 

They have a recall that is free and you take your 2.5i into the dealer and they will reprogram the ECU to correct this issue.

Excellent. Thanks for the info, I'm calling the dealer on my lunch break.

I just called my local Subie dealer and he said all the recall work has been done to my car. Is there anything else it could be?

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Fuel filter, plugs, air filter?

Perhaps the first time the reflash didn't work?

Have them reflash it again I went in TWICE matter of fact after the first time it was worse The Second time (2010) it was done correctly and there have been no issues since.

I made an appointment to take it in tomorrow morning. It's died on me twice. The first time it happened as I started her up. She started like normal then just died before the revs could bounce back up.

 

Then today, about 30 seconds after I started her up. I drove about 400 feet it first gear and put in the clutch and she stalled. It seems to only happen before she gets a chance to warm up.

 

Aside from the ECU reset, are there any other areas on our cars that this could be? Some problem area that stands out?

can this problem happen with auto 2.5i's ?

Yeah besides the ecu reset/update, what about basic tune ups. like plug wires, spark plugs, timing belt, o2 sensors, knock sensor, pcv valve, and fluids.

 

Some are spendy so some you don't have to do till you get an error code or certain amount of reccomended miles

 

I've done mostly all those on my 2000 besides the timing belt and o2 sensors which ill do the o2 sensors next week. I just replaced the pcv valve and just that little 12 buck part made it run a litttle better I noticed better idle and take offs

 

Soon it'll running like a champ :3

I made an appointment to take it in tomorrow morning. It's died on me twice. The first time it happened as I started her up. She started like normal then just died before the revs could bounce back up.

 

Then today, about 30 seconds after I started her up. I drove about 400 feet it first gear and put in the clutch and she stalled. It seems to only happen before she gets a chance to warm up.

 

Aside from the ECU reset, are there any other areas on our cars that this could be? Some problem area that stands out?

 

MAF sensor and the Idle Air Control Valve (IACV) could be at fault

MAF sensor and the Idle Air Control Valve (IACV) could be at fault

 

Yeah I always forgot about the MAF sensor aswell because mine is a MAP lol. I should check my IACV aswell

This has happened to me twice. Once in Baltimore when it was almost brand new (2-3k miles on it), and once in Florida right after the ECU recall flash in the fall when it first got into the 50's. Both times were when the engine temp was less than 60 degrees F.

I just got it back and it runs great now. The bill was bigger than I was expecting, but to have a car that runs as great as this one (my old car was a Kia Rio) is worth every penny.

 

The valve cover gaskets had to be replaced. They performed an "idle relearn procedure". Cleaned throttle body, fuel injectors.

 

She runs like a top now, can't wait for the next blizzard!

My car has 101,000 miles on it. I understand the timing belt needs to be replaced at 105,000 miles. Is there any real danger in waiting 4k miles to have it done?

omg... idle relearn aka pulled the battery and reset the ecu. sprayed carb cleaner in the throttle body. our cars are so easy to work on, hope u didn't pay more than 150 for the complete service. valve covers are very simple to do on our car.

omg... idle relearn aka pulled the battery and reset the ecu. sprayed carb cleaner in the throttle body. our cars are so easy to work on, hope u didn't pay more than 150 for the complete service. valve covers are very simple to do on our car.

 

Yeah, they soaked me pretty bad. I'm even mechanically inclined. I do all my own work on my motorcycle and every car I've ever owned. This car was bought for me wife, as I ride motorcycle 9 months out of the year. I just felt that it was better for them to do it as I've never touched a Subie, or even a boxer engine for that matter.

 

It wasn't cheap but at the same time I'm not financially ruined from it.

I just changed my oil and when I noticed my battery had some corrosion on it. I took off the red wire and brushed it clean. After that I went for a ride and my car 2005 legacy 2.5i automatic transmission stumbles at low low revs when I break at a red light or stop sign. Do you guys think this could be the same problem. I may completely disconnect the battery and try cleaning carb like you said

funny I'm having a strange stumbling issue just like this on my '11 CVT ... just made a thread too!