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Problem 1,976 with my Focus!

699 Views 18 Replies 7 Participants Last post by  Fockus
Here's this month problem. My idle has felt kinda rough for a couple months now. It doesn't stall, and the RPM needle doen't go up and down, it just feels rough.
To cure this, I've tried replacing the spark plugs with 4 Ford OEM double plats (gapped correctly), changing the air filter and I sparyed a little cleaner in the throttle body with no results.
But today, I noticed something that might be related to this problem and might help you help me.
When I have my foot on the brake pedal (like at a stop light), if I press down on both electric window switches next to me (to roll the windows up) at the same time and hold them down, the lights on the dash start flickering and dimming (very noticeable on the odometer) and the RPM slows down from 750 to 500 while the engine sounds struggeling. I can also feel a vibration (shaking) in my foot on the brake pedal.
When I release the switches, lights go back to normal and PRM goes to 1000 for a sec then calms back down to 750.

What is wrong with my car? I'm sure this is related somewhat to my poor idle.

BTW, it's a 2000 Focus ZTS sedan, automatic transmission with 56K miles on it.
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Take off your IAC valve, spray it out with carb clean, and put it back on. See if that fixes it.
Might want to see what your alternator is putting out. It could be on its way out.
Thanx for the replies! What's an IAC valve? What does it do and where is it?

For the alternator, what is it supposed to be putting out?
IAC is Idle Air Control Valve. The alternator should be putting out a minimum of 13.5 volts. To check, use a Voltmeter and measure the voltage at the battery (should be about 12.6), start the car and measure battery voltage again. Should be significantly higher. The IAC controls the Idle speed of the engine. It's right next to the throttle body.
If I am not mistaken, I beleive the IAC valve is on the underside of the Intake manifold runner number one. Or is this only on the 2000 manifold? Also it sounds like the ALT's voltage regulator is bad, and on our alternator it isn't repeairable. If you are running any kind of amp or high current electronics, this could be damaging and draining the battery which is causing the alt to work harder which is causing the eratic idle.
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Thanks everyone. I'll start by checking the voltage ouput this afternoon and see if there is a problem. I'm pretty sure something is wrong (maybe it's the alternator/voltage regulator, maybe it's the battery) cause beside the problem listed above, everytime I get in my car and it hasn't been driven for a couple hours, my power locks work but they sound very weak compared to when the car has been driven. Also, sometimes, when I open my drivers door (again, when the car has not been driven for a while), the chime sounds ultra-distorted and weird. These are not really problems, but might be related to my problem above.

But can someone explain to me how a bad alternator/voltage regulator would case the bad engine vibration that I can feel in the brake pedal and steering wheel when I press on both power window buttons at the same time?
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Bumping this thread cause I would like more opinions on this. I haven't had a chance to check my charging system cause I couldn't get my hands on a voltmeter this weekend. What do you guys think? Alternator on it's way out? Driving belt loose or dying? Belt tensioner dying?
It sounds like you might have two problems-battery and alternator. Also check all your grounds-from the battery to the body and the engine to the body. A bad ground could cause the erratic accessory operation you are experiencing. Look for corrosion, loose or broken wires. When you can get a voltmeter, check the battery voltage just after you turn the car off and then just before you start it the next time to see if the battery is losing charge while resting. A bad alternator bearing could cause vibration. The voltmeter is the key to troubleshooting this type of problem. 3 years is when a lot of batteries start failing.
i was thinkin alternator,,,go to autozone. they will hook up a machine to tell u if your alt. is dead/going dead/or fine. and they will tell you whats up with your battery too
Thanx guyz. Your help is greatly appreciated! I will do exactly what you suggested very soon (as soon as I get my hands on a voltmeter). The alternator/voltage regulator and/or battery problem does make sense but what I still don't understand is why the engine starts shaking (I can feel the shaking in my brake pedal and steering wheel) when I do press on both power window switches at the same time while at a stop lights (atx).
Ok so I checked my battery terminals and they are fine. And I've had the battery cable recall done last year. Also, I checked my charginsystem and the battery puts out ~12.6V before starting and ~14.6V at idle which seems fine to me. I'll see what the local Ford dealer has to say about this but before I go there, now that we know my alternator's not dying ... what could it be? How do you check if a belt tensioner and/or idler pulley are working correctly? (BTW, these are 2 different parts right?)
Just re-read your first post and had a thought-check the voltage when the car is running and it's doing what you describe in your post. If the voltage drops, then it might be the alternator after all. Have you checked all your grounds? a bad ground can work ok until you put a load on the system and then it will start to drop some serious voltage when a lot of current goes through it.
The idler pulley and tensioner are two different things. You can check them by removing the serpentine belt and spinning them by hand and looking/listening for noisy and or wobbly bearings. They should spin freely with no bearing noise at all if they are good. You will need a long 15mm closed end wrench to torque the tensioner and remove the belt. Make note of how its routed before you remove it.
Latest Updates ... maybe this will be useful to others with the same problem. The dealer replaced my alternator and the problem is maybe 50% gone. I did check my alternator myself with a voltmeter and it read 14.7V which I thought was good.

Anywayz, now, since the problem is still 50% there, the mechanic told me it is probably something related to the electric/fuel system. It might be the fuel injectors, fuel filter and/or spark plug wires.

BTW, the problem is that my engine seems to be vibrating/weird at idle speed or when I'm holding the brake pedal at a stop light (I have an automatic).

So right now, my car is at the dealer and they are changing my fuel filter. I'll go check it out at noon and if nothing improved, I'll have them clean my fuel injectors.
I think the '03 ZETEC has a different ignition module. I have had the same problem as you and I am looking to replace my Ignition Coil with and aftermarket one that I think should help.
Fuel filter changed, problem slightly improved, not 100% gone but definatly A LOT better than before I had my alternator changed and fuel filter replaced.

My car has 57.5K Miles on it so I should do the injector cleaning and spark plug wires soon anywayz. I'm guessing both those things will slighly improve my engine vibration issue and move me closer to a perfectly fine engine. I'll do those things a little bit later but for now, I'll just drive my car for a few days to really see if the improvements are there.

BTW, I hate the kind of problem I am having. I hate it when the problem "could be" multiple issues so you have to pay to have a lot of [censored] fixed with no guarantee that the problem will be fixed.
Have you had them check the motor mounts and the upper transmission mount.. sounds like one of them could be the culpret.
Also check the MAF sensor and make sure the connector is on tight....if this is undone, it will usually die at stops. Be sure to check the mounts though.
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How do I check the mounts myslef and where are they located and what do they look like? I asked the dealer to check this but he said that in order to see if a motor mount is defective or if there are small rocks lodged between the mounts (that could cause vibrations), he said he would have to take something out so it would cost me more money just to have it checked. Can I do it myself?
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