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-   -   2001 Ford Focus SE Zetec DOHC Idle Rough, Erratic, & Stumbles (http://www.focusfanatics.com/forum/showthread.php?t=290613)

ztsmith86 06-18-2012 08:42 PM

2001 Ford Focus SE Zetec DOHC Idle Rough, Erratic, & Stumbles
 
I currently own a 2001 Focus SE with a Zetec motor. The vehicle has a rough idle right now. The engine can be cold or warm the issue does not change. Withe the motor running in park the idle is a little rough. If you put the car in drive or reverse and hold the brake the issue becomes worse. Once in drive or reverse while holding the brake the engine shakes, idles becomes rougher, and stumbles, but never dies. I have watched the idle carefully and it seems to stay around 700 - 800 RPM in all these circumstances. The car runs very smooth while driving. There are no issues while driving, no shaking, no odds noises, just smooth sailing. I have no check engine lights and scan the vehicle every few days, but there are no codes or dtc being thrown. Engine temperature is normal and there are no fan issues. I also have no vacuum, oil, transmission, or coolant leaks. I have within the last month replaced all the following items:
  • Thermostat Housing, Thermostat, Thermostat Hosing, Upper Radiator Hose
    DFPE Valve, EGR Selnoid .... I checked the EGR Valve and it is working
    I have replaced PCV Valve & Hose
    I've Replaced all Vacuum Hoses, Removed/Clean Intake Manifold, Cleaned Throttle Body, Cleaned IACV, Cleaned Throttle Position Sensor, Cleaned MAF Sensor, Replaced Air Filter, Replaced PCV Filter in airbox
    I've done a Transmission Filter/Fluid Change, Oil Change, & Coolant Flush
    I've replace the Fuel Filter and checked fuel pressure after the regulator.
    I've check the spark plug wires, installed new OEM spark plugs, and installed new coil pack.
    I clean ever engine bay connecter with electrical connector fluid, blow dry with compressed air, and lubed with dielectric grease.
    I replaced the valve cover gasket, did a seam foam treatment, and fuel fuel injector cleaner in my last tank of gas.
    I've also power washed my underside of my engine to degrease it and there doesn't seem to be any leaks anywhere.
    I know this isn't and engine mount problem, so let's not go down that road.
    I removed, cleaned, and reinstalled both my O2 sensors.
    I did a compression check on all cylinders and compression is within spec on all cylinders.
    My voltage is within spec range in all RPM range.
    I sprayed either around my intake manifold to ensure I did not miss a leak and there are none.
    No fuses are burnt out and no relays or switches that I am aware of.
    The accessory belt visually looks to be in good condition and I inspected the timing belt and it visually looks to be in good condition.
    I know for sure there has never been any major engine repair done to this vehicle. My parents were the original owners.
    The struts, shocks, & tires are less than 1 year old.

    Please help me with this issue so I don't make the news for blowing this car up with a nuclear bomb ... lol sorry dark humor. The car has 179,000 miles, but is in prefect order in all other areas except this idle issue. It shifts very smooth and WOT is very good. I don't feel a lack in power either, but I did notice some small improvements all around after doing this maintenance/cleaning. The idle issue while in drive at a stop light holding the brake makes the whole engine/car shake moderately (enough to know there is an issue). Thanks for any help!

spiller 06-18-2012 09:25 PM

...Is there a difference between A/C on and off? My A/C is fouled up and not using it making it run poorly. (That's tough here in Memphis.)
I was in a similiar issue (maybe not as bad) with a bad accesory belt pulley. That thing got shredded after the bearing failed!
When was the last time the pulleys for both belts replaced?
With all else you've listed the last other thing would be faulty fuel injectors.

ztsmith86 06-18-2012 10:30 PM

If it were the injectors I think it would run bad through the whole rpm range and throw CEL. I have never changed any of the pulleys, but I don't believe that is the issue. Also it really makes no difference if the A/C is on or not.

spiller 06-19-2012 10:36 AM

You're right on the injectors, but besides the pulleys you don't leave much left...
My wife drove a couple hundred miles down into Mississippi and when see got to her destination, she said it was idling funny and had burnt rubber smell to it. I had changed the belts about 6 months prior, but also didn't change the pulleys. Well the accesory tensoner bearing had failed and eventually heated up and destroyed the plastic. Of course she was driving non-stop for a couple of hours and gave the pulley a long time to heat up like that and fail. It wasn't until she got to her destination that she smelt the rubber.
Between the age and mileage, those pulleys are still a good suspect.
My guess would need you to pull both belts and inspect all four pulleys. Most would say you should belts when ever you change the belts...

mpcv2000 06-20-2012 10:17 PM

Found this thread while trying to find answer about the exact same issue with my 01 Zetec Focus SE .
A/C no A/C is doesn't affect the issue but it is random and when it does the trouble , I get no DTC either but if I reset the battery the problem goes away for days if now week.
I don't want to change parts just for fun and the Original poster did change a bunch of things and he's having a similar issue.

In my case I'll have rough idle for a few days and after "0" idle.
I rest the battery and gone .

Any tips where to look at ?

spiller 06-21-2012 02:49 PM

Quote:

Originally Posted by mpcv2000 (Post 4224198)
Found this thread while trying to find answer about the exact same issue with my 01 Zetec Focus SE .
A/C no A/C is doesn't affect the issue but it is random and when it does the trouble , I get no DTC either but if I reset the battery the problem goes away for days if now week.
I don't want to change parts just for fun and the Original poster did change a bunch of things and he's having a similar issue.

In my case I'll have rough idle for a few days and after "0" idle.
I rest the battery and gone .

Any tips where to look at ?

Sounds like after resetting the computer it goes back to its base-line and then relearns a bad behaviour. I would clean and re"grease" your plug wires and especially any connectors to sensors that may have been replaced.
(Tom) out here might have some suggestions that would require capturing data while its running to maybe identify where the problem really is. Don't forget to check for codes that are in memory that don't light the MIL.
darn gremlins!

mpcv2000 06-21-2012 02:56 PM

I've found the problem this morning.
There is a hose behind the intake ( Vacuum ) that when engine is warm ( hose is warm too ) the hose colaps on itself and the engine start running very rough and then die.
When I reset the ECU it gives time for the hose to cool down and retake it's shape.
When the engine does it , just grab the hose behind the intake and squeez it the other way it is collapsed and the motor will run like it should.
I have put a worm gear clamp over it so it doesn't collaps until I get the hose from Ford.

I had this issue with a 00 ZX3 a while back and I kind of forgot about this "infamous" vacuum hose collapsing on itself . [cheers]

amc49 06-21-2012 05:15 PM

Vacuum leak. That hose can also bubblegum up and suck a small hole in the side to make the idle erratic as hell. One day or week it runs fine then just goes to crap out of the blue. Focus zetecs are known for it, at least the earlier ones. The PCV entry at the very bottom back of intake. I chased mine for a year before stumbled across it. The motor would run so bad at times that it would shake visibly as if it were going to jump right out of the mounts. No CEL ever registered, but finally did a realtime O2 sensor scan that showed no switching, stuck low volts at idle fuel trim limit. In short, most likely vacuum leak.

How were spark plug wires 'checked'? No more than 5K ohms per foot. Just changed out one on my '02, it had infinite resistance. Still worked 99% of the time, would just miss occasionally while calling for max power up say in passing situation. I've seen bad plug wire make OD disappear on a Contour zetec, that was wonky. It didn't even seem to run bad but changing the wires fixed it. These wires break the conductor internally real easy when pulling them for maintenance like plugs even if you're gentle.

oshoguno 06-23-2012 08:17 AM

If it is not a vacuum leak or the collapsed hose/elbow that is so common on these engines then I would do a Seafoam treatment (including the sucking up of the fluid through a vacuum line). I suffered low power, low idle and horrible mileage and did all of the usual stuff to fix, to no avail. I don't normally go for the "treatments" but I thought "what the hell" and gave it a try. What a difference! My engine has as much power now with the a/c on as I had before with the a/c off. I went from 450km per tank to 510km per tank on the next two fills. Engine runs smoother, idle is steadier and I am a lot happier.

cyfocus01 06-23-2012 10:07 PM

Yeah, sounds more like a vaccum leak/collapsed line. So are you doing work yourself, or had it done? Either way, that's a bunch of stuff done, and have it act crappy. My guess is a vaccum line broke or tore or something durring some of the work. So i'd really look into that. They say these early zetec super finiky to vaccum. Reminds me of early 80's escorts. Man, those were like finding a electric short.


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