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Old 01-23-2013, 09:38 AM   #7
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Join Date: May 2012
Fan#: 98657
Location: Latrobe, PA
What I Drive: 2009 Blue Focus SE

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Originally Posted by whynotthinkwhynot View Post
That sounds more to me like it's an engine running problem.

Typically the mount that causes the most problems is the front engine mount- or passenger side. That's the hydraulic mount. You have 3 mounts: the front, the transmission mount, and the torque-strut mount which is also called the lower/ dog bone mount.

I think my front mount went out very early, but I didn't replace it until much later in the car's life. I'm not upset by vibrations at stoplights. I just keep imagining myself as being in a hot rod- yeah, my 4 cyl shakes the car because of all that power! Anyway, go find your front mount, you'll see rubber surrounded by cast metal, with your finger push on the rubber part. It should feel solid. If it doesn't feel solid, then look for signs that the fluid leaked out- which if it doesn't feel solid, the fluid leaked out. That mount is toast if the rubber is not supported by fluid inside it like I described.

The lower dog bone mount is the one that you might hear go "thunk" if you floor the engine from a stop. That doesn't mean it's bad. It breaks several ways, but tends to be the most resilient of the mounts. The bracket that holds the mount to the engine can break. The rubber parts of the mount can wear out over time, and the bolts can rust in place making the eventual repair from normal use annoying. And yeah, rocks can get stuck between the mount and either of it's brackets causing vibrations.

The transmission mount is culprit #2 of vibrations. This one is solid rubber, but that solid rubber tears, and it can be manufactured out of spec so that the rubber part is too thin around the bolt. Imagine a flat piece of rubber bolted horizontally to the car body, then a bolt goes through the center of the rubber vertically, and then into the transmission to hold it in place. That's basically how that mount works. It is located underneath the battery bracket. To visually inspect that mount, the battery and it's bracket must be removed. If any cracks are spotted and verified to be cracks (not rubber left over from casting), then the mount must be replaced.

As far as what I think it probably is- engine running problems- how much do you know how to do, or want to do as far as maintenance on your vehicle? You have low mileage, but the car is old- 4 years now, and only 36k, so about 10k miles per year. That's great for keeping some things going, but it's hell on others. Mounts are one of those things that I feel should be least affected by time. I don't start looking for rubber decay on parts from age until closer to 10 years of age. However, it might be that your mounts sat on a shelf for 5 years before being used- that I don't know, and that's why I listed how to verify the mounts are good or bad for yourself.
Thank you for the very detailed explanation! The dealer told me that another guy came in with the same problem and he replaced everything from mounts to looking at the cylinders.. the whole sha-bang. The guy still have the rough idle even after all of this time and money was put into it. The dealer told me he didn't want to put me through the same thing because it is just a common problem with these cars, but causes no harm. I appreciate him telling me all of this, but seeing as the car hasn't always done this it just makes me feel like something is wrong lol.

I got my focus from a dealer that specializes in fixing damaged cars. My car had minor flood damage. The guy I bought it from said the focus is a great flood car because everything is locked up that is important. He doesn't buy flood cars that were submerged anywhere near the dash because then that causes electrical problems. Seriously, you would never be able to tell it was a flood vehicle. Everything is in excellent shape and it runs like a champ besides the idle lol.

As far as my experience goes... I don't have ... like any lol. I'm 19, but I'm learning.. My father knows this stuff for the most part so Ill def show what you said to him. Does anything that I said make any differences? Like since the car was in a flood.. that's why it is doing this lol?
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