2002 Subaru Outback Rattling

PLEASE HELP!!! Yesterday, I noticed a rattling sound coming from the entire car a 2002 subaru outback 2.5l 4 cylander (it seems a bit louder on the passenger side but it literally can be heard throughout the car). I was on the expressway and got off and stopped at a red light when the check engine light came on and started to flash and the rpm’s dropped rapidly and the needle began to bounce up and down. I pulled into a gas station to check it out more and popped the hood to find that when the car is rattling it is also shaking and rocking the engine of the car from side to side slightly. When I’m idling the rpm’s drop and the car feels like it is going to stall out. Then, as I accelerate, the rpm’s barely go above 2000 and jump up quickly between 3000 & 4000. It sounds like a metal on metal rattle with a very slight high pitched whistle and you can hear a fan kick on and the engine try to keep the rpm’s up every couple of seconds when the car is stopped. I had the timing belts replaced 2 years ago and it sounds very similar to how it did when they needed to be changed, however, the engine never felt like it was going to stall until yesterday. When idling the noise gets louder and when accelerating it can still be heard but barely. Also, the rattling has caused the entire car to vibrate all of the time. I noticed yesterday that the oil was low and topped it off, but I don’t think that would cause such a hige issue so quickly. When I go uphill, i have a good amount of power but every 30 second or so the car shifts and the rpm’s jump lurching the car forward because of the surge of power. Also, when I hit the brakes, my rpm’s jump slightly to about halfway above the 1 but the engine does not accelerate. Can someone please help me diagnose this problem and possibly give suggestions on fixing it? THANK YOU!

A flashing check engine light means you should stop the engine ASAP, according to every owners manual I have read in recent decades.

Sounds - literally - like a problem that needs a capable mechanic right there.

Above is correct, flashing check engine light means pull over immediately and have the car towed. You may have caused very expensive damage.

What they said.


The OP seems to be concerned about the rattling noise, when the flashing CEL is what she should REALLY be concerned about.

The flashing CEL means that the engine is misfiring, and continuing to drive it like that will likely lead to the very expensive catalytic converter getting burned-out. In other words, continuing to drive the car in this condition will lead to even more expensive repairs than are already necessary in order to cure the misfire condition.

The OP should cut her losses, call for a flat-bed car transporter (the car can’t be towed, due to the AWD), and have it examined by a competent mechanic. That means NOT bringing it to a chain-run operation like Midas, Meineke, Monro, Sears, Pep Boys, or <> AAMCO.

A competent mechanic will be able to figure out why the engine is misfiring (likely as a result of maintenance that was skipped) and as soon as that is resolved, the rattling should also go away.

Do NOT continue to drive the car in this condition!

Other than agreeing with others about not driving the car and having it properly diagnosed I might ask the following questions along with posing a statement.

You state the oil was low and you topped it off. How much oil was required to top it off and how many miles since the last oil change?

You refer to the timing belt making noise and “how it sounds very similar to how it did when they needed to be changed”.

Timing belts make no noise unless there’s a looming problem with a tensioner or idler pulley. Has this car broken a timing belt in the past?

Have you been driving this car with noise issues up to the point when the CEL illuminated and the current issues began?

Ok4450- i used 2 quarts of oil to top it off and I am also due for an oil change it has been about 3500 miles since my last one. The car has broken a timing belt in the past as well. I had been driving the car for about a month up until yesterday when the light came on and started flashing. About a month ago, a very slight rattling/vibration sound began and I figured that my muffler was a bit loose and admittedly let it go until yesterday when the even louder noise began. Two weeks ago, the check engine light came on and an even louder noise began. I was unable to make it into my mechanic because of work since then and am scheduled to meet with him tomorrow. I stopped driving the car yesterday when I stopped at the light after getting off of the expressway and the check engine light began flashing and my car felt like it was about to stall. Do these details possibly help? I just want to be informed on what the problem MAY be before I meet with the mechanic tomorrow so that I can narrow down the issue and also not pay for something unnecessary. Anything you can tell me is helpful. Thank you.

Good posts above for advice. Hard to say what’s causing this. Might be something simple, might not. I’ll offer some speculations, might help as you discuss this problem with your shop. Basically the first goal is to determine whether this is a spark, fuel, compression, mixture, or exhaust problem. Best of luck.

  • Plugged catalytic converter.
  • Misfires caused by problem with ignition system, i.e. spark problem.
  • Water or other contaminant in gas.
  • Belt-driven accessory is locking up, like the AC compressor.
  • Valve timing or compression problem, timing belt or belt pathway failure
  • Fuel filter clogged, faulty fuel pump, problematic fuel pressure, or balky injectors
  • EGR malfunction
  • Major vacuum leak, like the brake booster has failed
  • Serious internal engine damage, most likely this would be caused by a cooling system or oil problem.

@LucyLu222 I’m afraid I may not be of much help here. With the CEL illuminated and flashing the diagnostic code, or codes, need to be pulled first. Guessing a bit, I could say there’s a severe misfire based on the symptoms. The cause of that misfire could be any one of a number of things.

As to oil level, being 2 quarts down will keep an engine going but it’s not good for the health of the engine. Low oil means the remaining oil is overheating which then leads to oil coking; meaning the oil is burnt. This is not good on engine internals and especially so on variable valve timing mechanisms and turbochargers.

A gut feeling led me to ask about a timing belt snapping in the past. When this happens on a Subaru engine damage usually occurs due to cylinder head valve contact. The damage can range from minor to major with luck playing a part.

When this prior incident with a broken belt happened, was any engine work done or was the engine simply fitted with a new timing belt kit and sent on its way?
If the latter, I’m wondering if some minor damage has now surfaced as major due to not taking care of the problem at the time.