Scion xB Clacking Noise and rough idle

Hey there, oh wise and knowledgeable Car Talk Community. I have a couple of questions about my trusty 2005 Scion xB. First, a little bit about my car and how I use it. I have a 2005 Scion xB which I bought used about 2 years ago and has not given me trouble except for the dreaded power coil on the NUMBER 2 PISTON that niceLeighdone suffered a while ago. I do part time driving for one of those online car services in Baltimore that the cabbies loathe and the potholes in that town are going to be death of my beautiful car.

I am fanatical about maintenance with my car keeping track of the needed changes with an app on my smartphone

Issue #1, I notice that at low speed on rough roads, there is a clacking noise coming from the forward right hand wheel. It seems to match the rotation of the wheel. It only happens when I drive on uneven (aka BALTIMORE) roads at low speeds. I want to nip it on the bud before it becomes a mechanic’s boat payment!

Issue #2. I changed the power coil on the Number 2 Piston and it’s running well, but as I’m driving much more than usual the car runs a little rough when I’m idling on drive, like on a street light or stop sign. Now this is not that big a problem, but as I’m doing this car service, I’d like a smoother idling for the benefit of my passengers.

I love my Scion and would love at least a year or two more on it as it is a good, fuel efficient, quirky car!


How many miles are on it?

Take the car into a shop now so that your worries about a mechanic’s boat payment don’t become worries about insurance claims when your front wheel comes off on one of those Baltimore streets. The clacking can be anything - from completely benign to a failing wheel bearing or ball joint. There is no way to diagnose without laying hands on the car, but you do need to make sure it isn’t a critical item that is failing.

As for the rough running - that also comes with too many possibilities. How old are the spark plugs? You’ll want to check it for vacuum leaks. Clean the throttle body and idle air control valve (if it has one - might be an electronic throttle)… Addressing a little bit of a rough idle often just comes from doing simple maintenance things. I have no idea what is telling your phone app what to tell you, but I’ll bet it doesn’t tell you everything I would be doing with the car.

I have a similar problem with my 99 Camry when I go over washboar roads at slower speeds. It rattles and its the top of the strut. There is a bearing causing it and a service bulletin on mine.

The sparks are new. I added them about 3 weeks ago, when I replaced the faulty igniton coil on the Number 2 piston with a new one

My car has about 182,000 miles

I’ll have the car checked this weekend. TO THE MECHANIC’S FILES!!! My previous mechanics were taken out of business by Uncle Sam for engaging in a real-life Breaking Bad series!

The rap sheet was a mile long. Thanks cigroller for the advice. One of the mechanics on the Mechanics File is around the corner from when I live. Down side they don’t open Saturdays, but I’ll have it checked Friday morning at 8:30.

Sorry. Double post