[Kyo]

Greetings!

I have a 2005 ST, and for the last few months I've been having a bit of difficulty with it.

It began with a misfire on a cold and damp morning while going to work. The check engine light kept blinking the whole time, and when the cylinder came back the CEL went off.

A couple of days later, same thing: cylinder missing, CEl blinks but that time it stayed on after. So I went to the dealer, and had them take the code out of the computer (and a hundred bucks from my wallet). It had two codes: P0301 and P0304. So they swapped tha #1 and #4 coils (yeah, I know...) after offering to change the coil for 150$ a pop. Thanks, but no thanks... (since I can get one of those for 63$ from TeamFord).

It didn't fix anything, obviously - and after that I got my own OBDII code reader. The next time it happened, I was able to pin-point a way to make the problem happen at will. Let's say I'm exiting a highway to get onto another. Take the ramp, and when I'm about to accelerate (hard), I have somebody on my left, so I can't get on the highway just yet. Engine stays at 4500-5000 RPM for about 10-15 seconds (in 2nd or 2rd gear), and then I
floor it up to around 6,500 RPM, and that's when I find myself accelerating with a 3-cylinder Focus ST.

Every time I was able to read the codes, it always had the same two as before: P0301 and P0304. I was supposed to swap coils 3 and 4, but I forgot until it happened again last week. When I read the code, it only had a P0304 "pending" code. So I ordered a new ignition coil, and when it came in this morning, I swapped the #4 coil for the new one, and went for a ride.

Nyet komrade, still missing a cylinder while doing the exact same thing. When I came home, got the code reader out, but now I have 3 codes: P0300, P0301 and P0304.

P0300 is ransom misfire
P0301 is misfire cylinder #1
p0304 is misfire cylinder #4.

Now, I read that somehow the #1 and #4 cylinder are linked together (they fire at the same time I seem to recall??) as are #2 and #3. So I'm trying to find what could get me the misfiring? This is a coil-on-plug system, so I guess the only common component would be the engine's computer?

Has anybody experienced something similar?? I'm kinda lost right now, and I'm not sure what the next step should be in the troubleshooting of this...

Thanks for any help!!!

 

[xpeterbilt387x]

well first i want to say, never go the the dealership for getting codes. man thats a waste of money, AutoZone will do that for free. cylnder mis-fireing is usually caused by bad spark plugs and bad plug-wires. go ahead and change those and see if that fixes the problem, if not then try the coil-pack, they run about $75 bucks at AutoZone.

 

[Kyo]

well first i want to say, never go the the dealership for getting codes. man thats a waste of money, AutoZone will do that for free. cylnder mis-fireing is usually caused by bad spark plugs and bad plug-wires. go ahead and change those and see if that fixes the problem, if not then try the coil-pack, they run about $75 bucks at AutoZone.

Unfortunately, I'm in Canada, and there is no such thing as Autozone up here... as far as I know, no shops offer that kind of service, that's why I bought my own OBDII scanner in the first place.

Spark plugs are new - guess I should've mentioned that, it was the first thing I changed after getting the problem in the first place.

And since it's a 2005 ST, it doesn't have spark plus wires, neither a coil pack - the Duratec engine is a coil-on-plug system.

It really behaves like something is overheating, failing, and while it doesn't work - or works at a lower RPM - it cools down, and resumes working as usual again. Ii just can't locate the component that does that...

Thanks for your help!

 

[Kyo]

Still having the same problems, no solution found yet!

I had the injection system cleaned earlier this week, and the ignition system was tested at the same time. According to the tech, the ignition system is spot on, and very very stable under load.

This morning while going home from work, I tried it again, 5000 rpm for 5-6 seconds, then floored it - and voilà: one less cylinder, check engine light flashing. I got to the side of the road and shut off the engine. When I restarted it a few seconds later, the engine was running on all 4 cylinders, and CEL was off.

I checked for codes after getting home, and of course there were some: P0300, P0301 and P0304 - same codes as earlier.

Any help??

 

[fhh02a]

first of all let me say i have a zetec- so the world of duratech is a foreign one but i will try to help ya'

have you tried old stand by trick of resetting your ecu ? --thats only thing i can think of-- or try to erase the codes (w/code reader) and see if it throws it again

who knows --sorry not much help

 

[Kyo]

first of all let me say i have a zetec- so the world of duratech is a foreign one but i will try to help ya'

have you tried old stand by trick of resetting your ecu ? --thats only thing i can think of-- or try to erase the codes (w/code reader) and see if it throws it again

who knows --sorry not much help

Hi, and thanks for the help!

I did not try to reset the ECU, but I did erase the codes quite a few times, and they always come back whenever I provoke the problem... I'll try resetting the ECU and see what that does...

 

[whynotthinkwhynot]

I'm thinking an EGR problem, but I'd think that the sensors on the EGR/DPFE (one part, two functions) would've shown that it was stuck in one position or not working correctly.

Cylinder 1 and 4 do not fire at the same time, but on older coil pack systems these usually were run off one coil. That's probably what led you to think that.

First off, I'd be looking for what was causing the misfire. Physically trace down the coil wiring to be sure it's not damaged anywhere. Then grab some starting fluid. Idle the engine, and spray a burst of starting fluid in places where you think there might be a vacuum leak. If you find a leak, the engine idle will go up temporarily. Investigate further to see if there is a bad vacuum line, or something like an intake manifold, or air intake leak. Be careful not to spray starting fluid directly on the exhaust manifold- although it should be shielded so you're probably ok.

Let me know what you find, and any other conditions where the symptoms occur. I'd also run some STP fuel treatment- not FI cleaner- through the tank just in case you have a bit of bad gas.

 

[W8lifter]

I know this thread is old, but I thought I'd add something for anyone else who searched and found this. My car was doing the exact same thing as the OP's to the letter. Replaced my EGR and the problem's gone, even when I intentionally try to provoke it.

When I looked over the old EGR, it felt like the plunger was binding. While it was cold, I would pull it down with a small screw driver. It felt like it wanted to get stuck open. I imagine the problem got worse when it was actually on the car and getting hot and things were expanding.

 

[whynotthinkwhynot]

[gunfire] old thread resurrectors

Perhaps I got it right then although you'd think he'd get EGR codes as well, but I'm not entirely sure if there's a code for the EGR being stuck open. I think there are only low flow codes.

In order to keep from possibly poking a hole in your EGR diaphragm, use a section of vacuum hose instead of a screwdriver to work the valve. Simply the amount of breath it takes to fill your cheeks is enough to operate the diaphragm/valve. Then you can use a free finger to feel the reverse motion.

 

[W8lifter]

In order to keep from possibly poking a hole in your EGR diaphragm, use a section of vacuum hose instead of a screwdriver to work the valve.

If I was gonna attempt to reuse the old one, I would have. But since I bought a new one, I didn't really care about damaging the old one. It's getting chucked anyway.

 

[duo325]

I have the same issue. I had autozone scan my Check engine light.
I t came back P0102 - Mass air flow low input
P0113 Air Intake Temp hi circuit
P0301- Misfire on #1
P0316- Misfire at engine start.

I just bough a brand new MASS AIR Flow sensor. Installed it. Still same issue. Car would stumble and shudder at 2000-4000 RPMS and sometimes would idle erratic at start.
I bought a DPFE sensor turns out the 2005 ford focus has no DPFE sensor.

Im really getting frustrated..
NEW fuel filter new oil new plugs.

 

[duo325]

I fixed it. And I feel like a idiot...
I spent:
Mass Air flow sensor: 150.00
EGR Valve : 50.00
TPS : 30.00
New battery : 150.00 "optima red top"
DPFE: : 50.00 2005 focus has none i need to return the part.

Total spent 430.00


Problem was a dirty Idle Air Control Valve: WD-40 and some q tips. fixed the problem.

yea i know it was a lesson learned.

 

[redst]

Does anyone know if the OP, kyo, resolved their issue? If so, what was the cause? I have the exact same issue under the same driving conditions with a misfire code on the same 2 cylinders.

 

[Kyo]

Does anyone know if the OP, kyo, resolved their issue? If so, what was the cause? I have the exact same issue under the same driving conditions with a misfire code on the same 2 cylinders.

Hi,

The issue I had just... went away. For a while I just got careful not to provoke the problem since I knew how to do it, and after a long while I got bored and did it anyways, and the problem never came back... I'm not sure why though.

I had ordered a new coil from Bill at TeamFord, and swapped it, but the problem was still there. So I swapped the new coil from cylinder until I had done the complete cycle, and the problem was still there. I finally got my car at the dealer again to have the ignition system checked, but their specialist said that the whole thing was very stable and he couldn't see what was wrong. He suggested that I had my injectors cleaned, so I had him do it. When I got out of the dealer... problem was still there, that's when I thought: "[][][][][] it, I'll just go easy on it until I can find something"

And after a while I discovered that the problem went away. It's been a few years now, I still have my ST and the problem never came back. Was it the injector cleaning? Not sure... I don't think the the EGR valve was ever touched either...

I'm getting a new car on monday, I thought I would trade-in or sell my ST, but last week my wife said she wanted it (as did my two sons and one of my colleagues), so she gets it and is selling her car instead. That just how good this car is, after 224,000 km (140,000 miles) and 9 years in pothole province...

Hope you can find the cause of your misfiring problem!

 

[redst]

Update:
To be clear, I had exactly the same issue as the original poster: same load condition (sustained high rpm at light load followed by heavy acceleration caused misfires) and the same DTCs (misfire cylinder 1, misfire cylinder 4, and no other codes).

During initial troubleshooting I found that my positive battery cable that runs to the starter had significant corrosion. Observation of the cables noted that the coil packs receive power from this circuit. I proceeded to remove the corroded section of cable and install a new terminal.

To date the problem has not re-occurred. I have attempted the load condition 4 times over 2 different days without issue.

I hope this helps somone else before they start dropping money on plugs and coil packs. Total cost of the repair: $7

Thank-you Kyo as I would not have been as suspicious of the battery cable if it wasn't for your help!

Shawn