The Ford Vibrator

I have a 2004 Ford Focus. 3 or 4 years ago, the battery light came on. Mostly it flickered; sometimes it was steady. Several different shops could not find the problem. Then about two years ago the check engine light came on. At the same time, the car developed a horrendous vibration at low speeds. At times, the dashboard would vibrate and all loose things in the car would rattle. Again no one, at major chain or independent shops, could find the problem. Finally, an older mechanic thought to look at the crank pulley, which was wobbly. He replaced this. The check engine and battery lights are off for the first time in years, but the vibration is WORSE. W-a-y worse. Driving around town is a bone-jarring, tooth-loosening experience. Where to go from here? Can’t buy another car at this point.

How many miles on this car? Manual or automatic?

If the original crankshaft pulley was loose on the crankshaft there may be damage to the crankshaft. If that’s true it may be impossible to correctly tighten the new pulley.

Go back the the mechanic who installed the new pulley. I can’t believe he didn’t start the car after he installed a new pulley. If he did he surely felt the vibration. If he didn’t I’d want to know why.

Driving the car this way could cause damage.

138,000 miles on this automatic
The mechanic did start and drive the car after replacing the pulley, and felt the vibration , but said no more could be done. My guess was that the wobbly pulley was a secondary sign of deeper trouble, but was told not. Or that if it was, there wasn’t much that could be done.

The “pulley” as you call it is actually a harmonic balancer. SOMETIMES it is also used as a method of PRIMARY engine balance. Four cylinder engines are naturally balanced, that comes with the design…

Occasionally, torque converters, part of the transmission, become badly unbalanced but there are usually other disturbing symptoms…

In YOUR case, the “wobbly” pulley may have buggered the nose of the crankshaft, making it impossible to correctly install a new one… Or the pulley may have nothing to do with ANY of this…

Does the car have to be moving for this to happen??

No. The vibration occurs when the engine is idling, and at low speeds. The highest I’ve felt it is at 40mph. I live in the boonies, so do a lot of traveling at 55 or so, and don’t feel it then. When I get into town and run errands, it is pretty much constant, but not always at the same intensity. When the mechanic popped the hood and had his asst. rev the engine, I could see that the pulley wobbled at low revs and was smooth at higher revs. One thing that changing the pulley did was cause the check-engine and battery lights go off for the first time in years

Changing the crankshaft pulley on a Focus was probably fairly difficult and may have required partially removing the engine to gain working room. Wiring connectors may have been opened and re-connected. This is the only explanation for the warning lights to go out…As for the vibration, that’s a mystery. The harmonic dampener or balancer, part of the crank pulley, protects the crankshaft from torsional vibration, NOT the kind of shaking you are feeling…

There’s a number of things that could be behind this considering how long this problem has existed.

An engine compression test should be performed as a first step. This will weed out any internal engine fault that may be behind a vibration caused by a poor running problem. After that plugs, wires, etc. should be considered.

I kind of agree with Caddyman about the crankshaft nose. If you’re saying that you can see the pulley wobbling at low RPMs after that pulley was replaced then it could be that the crankshaft nose is wallowed off.
After 2 years of that, I don’t see how the crank nose could be anything but garbage.
Considering the lengthy history behind this problem a mechanic should go over that crank nose with a fine tooth comb before even considering replacing the pulley.

Actually, the pulley replacement was quick (3 hours) and relatively easy. Access is direct - no need to remove any part of the engine, or disconnect any wires. I was informed of the process and shown the parts necessary to do the job. (The mechanic is an older guy in his own independent shop, and likes to take the time to teach his customers about their cars and what he is doing to them.)

I will have a compression test done asap. It hadn’t occurred to me, because the car is so lively and has such quick, solid acceleration, especially up hills.
Somehow, there’s been a misunderstanding. The pulley has already been replaced. It no longer wobbles. The vibration is still there, and much worse than before. The pulley itself and the vibration seem to be separate issues, except for the fact that the vibration is now worse. My concern at this point, is where to go from here to find out what is causing the vibration.
I believe the battery warning light went off because the pulley’s previous action was causing the serpentine belt to not articulate well with the alternator.

There Are Warnings And Special Tools Required.

Ford says some 2002-2007 vehicles equipped with a 2.3L or 2.0L Duratec engine can suffer damage if the crankshaft bolt is loosened without using special tools (crankshaft timing peg, crankshaft alignment plate, a holding fixture, and an adapter).

From a Ford Motor TSB: “The crankshaft pulley also retains the crankshaft cam drive sprocket which is NOT keyed to the crankshaft, so valve timing may shift if the pulley bolt is loosened.”

Before any loosening of the crankshaft bolt, valve timing must be locked by the special tools.

CSA

Ford Also Has TSBs Regarding Excessive Engine Vibration At Idle For 02-07 Focus.

Small stones, road debris, and ice/snow pack into the rear engine roll restrictor. You’re supposed to clean it out and install a shield, part #2M5Z-16102-AA by removing and reinstalling cross member-to-roll restrictor bolt.

CSA

The ‘special tools’ were obtained and used by my mechanic. He showed them to me and explained their purpose and use.

Super! Did You See The Thing About Dirt & Rocks In The Roll Restrictor?
CSA

Yes, and I will also have this checked out asap. Sounds like a possibility. Thank you.