[Bean]

2004 ZX3 2.3l pzev 85k miles

Description of general symptoms: Idle settles around 750 rpm but then it will get rough after less than a minute, progressively worsening and sometimes as if it's going to stall. I don't wait to see what will happen for fear of making it worse, so I'll either throttle a little or shut it off. When it's worst it will immediately drop into it's stuttering idle when the revs drop, instead of going to a steady idle. And at those times I sense a hesitation when I throttle like I need to give it more than necessary to maintain a higher rpm (1500-2000). Also noticeable putt-putt sound from exhaust around when it starts stuttering. Seems worst after stopping after my commute (just 15 minutes in suburb driving), but honestly tough to determine a particular environment that makes it worse. CEL would turn on occasionally but would go away (*since I had one coil replaced almost year ago, background on that below).

Fault codes: (current) P2195 (Front HO2S Signal Stuck Lean bank1 sensor1)
(pending) P0300 (random/multiple cylinder misfire)
(pending) P0316 (misfire detected at startup)
The pending codes appeared once a few days ago. Have not recurred, even after numerous drives and idling for several minutes while monitoring engine.

When I monitor the engine tests through the Torque App I see some misfires occuring on Cylinders 1, 2, and 4. Between 10-20 on average, and cylinder 3 will occasionally register a misfire as well. These tests usually do not register as FAILS, though I have linked to a test that did which occurred during one of the almost-stalling while idling moments. Also not sure what to look for regarding vacuum readings from live data. Seems to stay around 20 at idle, sometimes lower around 19, even 18. Does not seem to drop dramatically when RPMs dip as it stutters while idling.
LINK TO MY TEST DATA: https://drive.google.com/file/d/0B71DAMgsL-jTcl9XTlVOX292VU0/view?usp=sharing
This leads me to think either:
a) The three older coils are bad (which i get the impression is unlikely from reading forums) OR
b) There is another problem... research on here suggests the PCV Hose (today will take car to dad's garage to put on ramp and get under it to see if I notice any leaks.)

Does it make sense for a lean condition to cause more misfires on older coils than a new coil? If I were to replace all the coils would it mask another problem causing more issues in the future? (As well as wasted $ on new coils). I will try the newer coil in another cylinder today but I suspect it will perform the same. Just had limited time available to work on car recently (this is my one day off)
Would bad coils causing misfires also create a putt-putt effect at the exhaust?

Last week I replaced one plug BOOT (coil on plug). Originally intended to replace all of them after having one coil replaced and doing research online suggesting that the plug BOOTS could make it seem like bad coils (*see below for background). I replaced the boot on cylinder 1. That did not seem to help. Before replacing other plugs boots I got an OBDII reader and the Torque app - NOTE: I am new to this, most of my mechanical experience came from working on an '83 VW Rabbit and an '82 Honda motorcycle, and otherwise doing routine maintenance on other, newer, vehicles (oil changes, brakes).

If somebody could look through my OBD test data (link above) and see the significance of other FAIL tests that would be greatly appreciated. Or suggest other items I should look for using the tool. I did hours of research online and am afraid I am confusing what is significant and what is normal. (Reading through: http://www.motorcraftservice.com/vdirs/diagnostics/pdf/OBDSM407.pdf has been of limited help given I am a novice).

I will updated with what I learn today after poking around under car and testing new coil in a dif cylinder.
Thanks so much for any help!

Alex

*BACKGROUND on previous coil issue. Had a bad coil last January. Started car up, drove down driveway. Noticed stuttering, hesitation on acceleration, almost stalling from idle. CEL blinking. Put car back in driveway, got mechanic from shop down the street to come by with a computer. He pulled plugs on coils while car was running and was clear one coil didn't make a difference un-plugged. So that was easy and they replaced it. Another coil may have had issues but they weren't sure and I opted not to replace all of them (believe it was cylinder 1). They replaced all spark plugs too.

Edited: to clarify I was referring to plug boots not sparkplugs.

 

[Marde]

Is you car a manual trans?

COP's failing is kinda rare, but yes, it does happen. My guess says your COP's are not causing your misfires.

What type of spark plug are you using? Pull them out and check the health and "the look" of them. What are the gaps set-to on the plugs?

The Hose on the PCV-to->the back-side of the intake manifold is either; too old and cracking now -or- it will be very soon. A 2004 Duratec with the original PCV hose = gotta change it soon.

Check out this thread->
http://www.focusfanatics.com/forum/showthread.php?t=212938

Your Vac pressure measurements are the same or similar to mine. I also use Torque.

When engine is fully hot + No brake pedal applied + ATX in Park + A/C off = Vac pressure 21.1 - 21.4

When engine is fully hot + Brake pedal applied + ATX in Drive + A/C off = Vac pressure 19 - 19.6

When engine is fully hot + Brake pedal applied + ATX in Drive + A/C on = Vac pressure (gets low on my car) 15.5 to 15.8

 

[Bean]

Got misfire on cylinder 1 again on drive home P0301, other cylinders fine. So it seems that it is specific to that cylinder. Swapped new coil from cylinder 3 to cylinder 1 and got misfire on cylinder 1 still! So it is not the coil. Also didn't see any obvious intake leak, but didn't get to do much testing and was surprised by the coil result which suggests to me it's not a leak. Dad said engine/exhaust sounds like misfire and suggested changing spark plugs (they are 10 months old).

Can an intake leak create misfire primarily on just one cylinder? Will have to start researching again.

Starting with spark plugs... probably will take car to local shop where they replaced all 4 spark plugs and 1 coil in January... probably worth the convenience for me even if spark plug doesn't fix it (but if it does should be quick and free). And maybe they can easily check the other electrical connections there and the harness.

 

[Bean]

Is you car a manual trans?

What type of spark plug are you using? Pull them out and check the health and "the look" of them. What are the gaps set-to on the plugs?

The Hose on the PCV-to->the back-side of the intake manifold is either; too old and cracking now -or- it will be very soon. A 2004 Duratec with the original PCV hose = gotta change it soon.

Check out this thread->
http://www.focusfanatics.com/forum/showthread.php?t=212938

Thanks for the reply and the vacuum numbers.

Yes, it's a 5 Speed. Is that significant?

Will update with what I learn about the plugs.

I saw that PCV Hose replacement thread (bookmarked) and not looking forward to doing that but will be nicer when I have a garage available soon (weather). Guessing it's not responsible for the misfire though. Car is running well otherwise (when not misfiring that is).

 

[Bean]

Well I plan to just take it to the shop in the morning. The CEL was gone on my last drive, which is very odd as the problem is still very much there and fault codes are still readable. Will ask them to check anything obvious with the spark plugs or wiring on cylinder 1 and also for intake leaks. Knock-on-wood just a defective spark plug on that cylinder...

Any suggestions for what I should tell the shop or look out for? They are respectable, but also a large operation. Said they only schedule 1 CEL a day (I can see why).

Spent a fair amount on the car past couple years, would like to keep it at least one more. Must say it's been relatively trouble-free, especially mechanically, engine and drive-train solid, so it sorta averages out. Hopefully the recent issues and headaches will be followed by a trouble-free year.... seems like these cars and engines are desirable so might be easy to sell instead of trade-in when it's time for a new car.

Too tired to write without rambling & ranting. Sorry for that!

 

[Marde]

Yes, it's a 5 Speed. Is that significant?

Not significant to the problem, was just wondering. Some people believe Stick-Owners are genetically superior and more intelligent because they bought a stick. jk and not jk.

Any suggestions for what I should tell the shop or look out for?

Nope. T-shoot a misfire, they can handle it.

 

[Bean]

Not significant to the problem, was just wondering. Some people believe Stick-Owners are genetically superior and more intelligent because they bought a stick. jk and not jk.

Hah. That's great. I agree there is something particular, and generally good, about people that choose to drive stick these days, not sure intelligence is it though I know people that thought clutches are meant to wear out frequently... Mine still feels like new (I'm surprised about that myself).

Wish me luck tomorrow! Will try to contribute something helpful to the forums here too, in the appropriate threads of course (eg. acceleration grinding noise from CV joint).

 

[dave89iroc]

You mentioned that the plugs are 10 months old...make sure that when you have it checked by the shop that they are not Bosch plugs, specifically the platinum plus 4

 

[Bean]

You mentioned that the plugs are 10 months old...make sure that when you have it checked by the shop that they are not Bosch plugs, specifically the platinum plus 4

Dropped off this morning. Asked what plugs they use since I read it could be an issue. Tech said they use NGK, the best plugs according to them.

 

[Leora83]

Yay, another yellow hatchback still running!
Mine is a Zetec, but it hates Bosch and loves NGKs, for whatever weird reason.

 

[Bean]

Yellow was only color available as stick shift, but I totally love it. Don't know what genius came up with the "egg-yolk yellow" name though. Egg yolks should be orange IMHO

The shop called this afternoon saying they drove it around for a couple hours and didn't get a CEL or faults. I had told them to just let it run idling to see the problem... so I told them again. Called me this evening saying they found a small leak in the throttle body (think that's what they called it). They ran out of propane and will finish diagnosing tomorrow.

They also mentioned might be problem with O2 sensor, but I'm guessing that's just a side effect, not a cause (told them as much too.)

 

[Marde]

So? Maybe new spark plugs got it fixed? -and despite of the possible TB vac leak. Did they comment about the condition of the old plugs? You had misfire DTC's and maybe now you do not? Wishing you luck on your next few drives. Cheers!

Edit: wait, did they replace the plugs?

 

[Bean]

Diagnosis from the shop:
- PCV Hose collapsed. Cost to replace PCV intake/box and hose = $640
- O2 Sensor not working/reading - $336

I told them I'd probably take it home and they have already put it back together. Cost for Diagnostics - $218 (2 hours, said it should be 3). It's included in the quotes for the jobs above.

Figure it's well worth it to spend time to do PCV hose myself and not too difficult. But the other items? Don't have time at this moment to research cost/difficulty level of PCV intake/box or the 02 Sensor (if it really does need replacing).

Any input would be handy about this.

Regarding spark plugs - guessing they were fine but didn't ask. They were new, from January.

Might need to start a new thread to decide whether to fix or to sell the car, it's had a fair amount of work done on it recently. Coincidentally a customer (at my family deli) told me she's selling her '99 Subaru Forrester ~ $1200 - might talk to her mechanic as it sounded to be taken care of well too.

 

[Marde]

Est repair cost do seem a little high. but not crazy high, it's just pro garages have hourly rates that are often tuff to swallow. You can (with some help?) do these repairs yourself. One option, to make it easy, is to hire a friend, or anyone with mech skills and some tools, and do the work together.

The O2 sensor: Did they tell you which one is bad? Your Torque App allows you to monitor both O2's in graph-like form-> Have you done this? Replacing an O2 sensor is kinda easy. A special tool is needed, O2 removal socket, and can be borrowed from some car part stores, Free, but with deposit. You might need to check fuses and ring-out the wires before replacing an O2 sensor. A new Ford O2 sensor is about $60.

The PCV Hose: Go back to the link I provided earlier. The job is easier than the OP made it look. No need to lower radiator and use that super long extension method he did. You can do it. A new Ford PCV Hose is about $40. I can do this job in about 3 hours, and I am slow, and not a mech by trade. 4 or 5 hours if you include breaks and lunch.

 

[Bean]

The O2 sensor: Did they tell you which one is bad? Your Torque App allows you to monitor both O2's in graph-like form-> Have you done this? .... You might need to check fuses and ring-out the wires before replacing an O2 sensor. A new Ford O2 sensor is about $60.

The PCV Hose: Go back to the link I provided earlier. The job is easier than the OP made it look....

Upstream o2 bank 1 sensor 1. I do get a reading from the bank 1 sensors in Torques live-graph view. Not sure I'm getting results from the bank 2 sensors. Tried switching to bank2s1 and didn't see any movement, was testing briefly in driveway. The test results show incomplete right now for all the o2 sensors but I'm guessing that's because it needs to be driven or run longer. I have not found a guide to diagnosing o2 sensors with Torque, nor do I even know how many sensors the car has. Need to find me a manual, just seems like nobody is pro the Hynes or Chiltons. Will try to find the answers on here one at a time, and search for a service manual online (or pay for a subscription when I have parts in to do the work).

Car is definitely running worse, more misfires, than it was before taking to shop. But I imagined it would be as the work would make the leak worse. There are also some new fault codes, probably from their testing. . Can see them here: https://drive.google.com/file/d/0B71DAMgsL-jTMVREek5CS09td1k/view?usp=sharing

What about the PVC intake/box mentioned? Does that just refer to the valve?

Need to order some parts now, or soon as I figure out what to get. Any quick suggestions for a shopping list?
O2 sensor:
PVC parts: (Maybe this Toyota part http://www.focusfanatics.com/forum/showpost.php?p=3838006&postcount=57)
Intake Gasket? (was on the quote from the shop).

 

[Marde]

I have little time to type, but here is a quick reply. The Focus does not have Bank-2 sensors, so forget about those. PZEV cars like mine have 3 O2 sensors. Yours? -guessing is not PZEV, so yours has 2 O2 sensors.

Just peeked at your link. Ahhh!! I see. Yes, B1S1 is lean so you might want to check the wiring of that sensor AND do it before ordering a replacement O2 sensor. NOT sure if a Lean Code can be caused by a wiring problem? -guessing not. Strange, I'm guessing that most lean conditions would be a lack/low fuel pressure thing... and this makes me wonder about your fuel pressure/flow health. And typical misfires = a Rich condition. During a recent test, I removed and placed my B1S1 outside of the engine exhaust manifold and got the same Lean DTC.

No, do not get the Toyota hose. Yes, it can be mod'ed to make it work. blah. -nah.

IM gasket on most cars = ALWAYS replace it. Our car has a very durable and unique gasket that in most most cases can be reused.

I think those guys at the garage might have bumped, messed-up, disconnected one of your IMRC vacuum hoses. Don't take any action on that P2004 DTC right away. -talk later; and hopefully other FF's here may help and add additional info.

 

[Marde]

Misfires on 1 and 2: so... take the COP's & boots out of 1 and 2 and replace them with the COP's that are on 3 and 4. Clear all DTC's... And then do some test drives.

Edit: If no change after above COP swap-> suspect defective spark plugs on 1 and 2 -or- maybe bad cylinder compression on 1 and 2.

 

[Marde]

Uhmmm... I have kids so I am often distracted...

You also have a P0122: Throttle/Pedal Position Sensor/Switch A Circuit Low Input.

I'm not sure what to make of this, but you do not want to discount it. Your Torque reports suggest other make/model stuff. Check your vehicle/car profile in Torque.

Is the P0122 DTC displayed when using another scanner? Get a free scan at any/most auto part stores.

 

[Marde]

Misfires on 1 and 2: so... take the COP's & boots out of 1 and 2 and replace them with the COP's that are on 3 and 4. Clear all DTC's... And then do some test drives.

Edit: If no change after above COP swap-> suspect defective spark plugs on 1 and 2 -or- maybe bad cylinder compression on 1 and 2.

I forgot to mention the possibility of a fuel injector problem on Cyl-1 or 2. Oddly enuf, I too have a engine problem (with no DTC's) and will be digging into. removing, testing. cleaning fuel injectors soon. Good night Sally.

 

[Bean]

Thanks for the very helpful answers. I do have PZEV, so that explains the 3 o2 sensors in front.

Will order a Ford hose and gasket if available at an autoshop so I can return it if it's not needed. I think that will likely fix the misfire issue.
How about the PCV valve? Or a PVC intake/box? Think they assume those parts need replacing when really I just need the hose?

Those other two fault codes (manifold, and throttle/pedal) only appeared after the shop worked on the car yesterday and I expect them to disappear (I asked them about it after doing a scan while in their lot before driving away using Torque).

Sparkplugs and Coils should be fine as I asked about them and suspect it was one of the first things they checked. The increase in misfires on cylinder 1 and 2 after they worked on it is likely just from the intake leak worsening.

Will look into what/where the IMRC hoses are, probably will involve taking manifold off anyway though it'd be good to know if I need any additional parts for that.

Thanks so much for your help. Will try to find a garage where I can work on the car this weekend or early next week.