[Stevenz1inoc]

First let me say I love this forum already! Last weekend my girlfriend purchased a 2004 Focus with 106,xxx miles. It has a clean carfax with a well documented service history at regular intervals from Ford Dealerships. The carfax even shows that the 90,000 mile service was done at 94,xxx miles. She has put exactly 106 miles on the car since buying it last Sunday. It's been flawless. Super smooth, very quiet, and honestly sounds just like a brand new car. Fluid levels are all good and it shifts perfectly. Car has lots of power too. So here is what happened.

Last night on her way home she said the car started to idle rough. She said the AC was off, she was in drive and at a stoplight. When she accelerated it took off like normal and ran just fine from what she could tell. She got home and called me and described the problem. I had her go outside and start the car and see what it was doing. She started the car and it was running so quiet and smooth I didn't even know she had started it and she laughed. The car was still warmed up from her drive home. She put it in drive and her foot on the brake and idled it for a bit and nothing. It was as smooth as could be.

I got on the forums and have read all about the PCV hose issues but then I realized I was reading the fix for that regarding the 2.0L engines so I researched and found that on the 2.3L I might have to actually pull the intake to fix it. I'm very mechanical and while I don't want to do this I will have no trouble doing it but I am thinking that since this is intermittent that maybe it could be something else? What do you guys suggest? If I do need to replace the PCV hose can it be done from underneath without pulling the manifold? I didn't see where anyone had tried that or given an answer to that question.

Thanks for reading and I look forward to all the fun we are going to have with this car!

 

[sailor]

More of a repair question, so I've moved it to General Tech Chat for more looks.

On mine, this ended up being a coil going bad - but it took a while before intermittent symptoms got bad enough to prove which one, and I wasn't going to throw 4 at it on a guess (expensive).

Plugs if not prev. replaced was my starting point, to rule that out. Many will mention coil "boots" (the connector from coil to plug) next, as they aren't expensive & seldom get replaced.

It has to actually go on for a while or have a fairly bad miss for a bit before it'll light a CEL, but a scan tool that's one step above the most basic code reader can check for a misfire count before it'll even set a 'pending" code - that was the tool I used to confirm my issue. Moving the coil with the reported problem to a different cyl. confirmed the spark/coil issue as the problem followed it.

Same year, same engine, so it MIGHT be a similar issue.


P.S. - many use AR104 Autolite plugs for a cheaper "performance" substitute over the stock Platinum plugs. They work better new, but don't last the 100k of platinums (AR103's for a "colder" one for high performance). Spark Plug "stickie" in the duratec section you posted in originally discusses this, used them myself for the experiment to check if plugs were an issue.

 

[Stevenz1inoc]

Thanks Sailor, I appreciate the move to a more active area and the advice.

I just got off the phone with my girlfriend and she is headed over to my house so I will be looking at it. She gave me more of a description just now and described it as kind of a bucking or surging???

If it is a coil I think I could go ahead and buy one and swap it in and keep moving it to a new location until the issue goes away and that way I could figure out which coil it might be?

So is this sounding like the PCV or EGR at all?

 

[Stevenz1inoc]

UPDATE to the issue

So my GF got to my house, we drove it and no issues, we go eat dinner, come out about an hour later on the drive home it happens. Engine RPMs are dropping. By the way, I hooked up my OT-2 scanner and no codes, no misfires showing. RPMS are running about 740-760 but when the issue happens they drop to about 600. I have the log file but not sure I recorded the correct info. I have been told that I need to record short term fuel trims and if they are close to 0 then it is okay and not a vacuum leak but I'm not sure about that info.

When she shut the engine off I did hear an air like hissing/leaking noise that sounded like it was coming from the front of the engine near the intake but I am not sure if that is any indication but this sound was repeatable over and over, start and turn off and it did it 3 times.

I really could use some help here guys. I am an old school Mopar guy and while I love the Fords I just don't know enough about this focus to figure out what is going wrong.

 

[amc49]

Can be PCV in the early stages, they sometimes bubblegum up hose to leak then they reseal and run fine. Later the leak gets worse and permanent bad running then.

Bucking and surging higher up than idle lends toward ignition issue, a PCV vacuum leak shows most at idle and seems to disappear with higher engine speed since the leak percentage wise is less of total mixture then.

 

[Stevenz1inoc]

Yes this is only at idle and when the engine revs or you start going down the road it goes away.

 

[sailor]

Not sounding much like an Ign. miss then.

My dieing coil showed up as an on throttle miss at low rpm (intermittent) first. OK idle, cleared up at higher RPM.

 

[Stevenz1inoc]

I just took the IAC off and also got a good look at the Throttle body. Someone has cleaned the IAC and TB recently in an attempt to fix this issue. We just got this car last weekend from a used car lot, not a major dealership. I got under the car and cant see the hose at all. I took a look at all the connections that need to come off to get the manifold off and it doesn't really look that bad but I cant see all of the bolts that actually hold the manifold on. I'm not even sure the PCV hose is the problem yet but we are going to take it to ford to get an estimate and see what they say then I will know what I need to do to fix it. Hopefully!

 

[Stevenz1inoc]

Latest update

So we took it for a longer drive today to the Ford dealership that actually did all the service on this car. Carfax showed them as the main place it was taken. We get there and the service writer recognizes the car and remembers the old owner and pulls up the entire service history on the car. He was the one to write up the 90,000 mile service don't at 94,000 miles, about 8,000 ago it was pretty funny. Anyway....

On the way to the dealership it did the studdering/jerking at highway speeds. it had not done that before, only at idle. Can this still be the hose to the PCV valve? Also I have noticed that when you turn the engine off, you can hear a hissing sound coming from the front area of the engine and it's not the AC because we have turned the AC off and run the engine for a few minutes and then checked it and it still does it.

So before I tear it apart, I just need to know if these is sounding like the PCV or maybe a Maf or a coil that have not thrown a check engine light yet?

 

[amc49]

The hissing could easily be coolant leaking down pressure from a plastic tank cap not quite tight enough.

 

[Stevenz1inoc]

No coolant leaks that we can detect at all, fluid levels are at the same levels as last week.

Good news though. Just got back from the small independent dealer we bought it from, told them the issue and what we think the problem is. I am buying a new PCV hose, valve and the felpro intake gasket kit and they will install everything.

We are still not sure 100% if this is the issue but at least it will be fixed and I wont have to worry about it being the cause. If this doesn't fix it then I will take it to Ford and have them Diagnose the issue.

 

[Dayna2.3]

More of a repair question, so I've moved it to General Tech Chat for more looks.

On mine, this ended up being a coil going bad - but it took a while before intermittent symptoms got bad enough to prove which one, and I wasn't going to throw 4 at it on a guess (expensive).

Plugs if not prev. replaced was my starting point, to rule that out. Many will mention coil "boots" (the connector from coil to plug) next, as they aren't expensive & seldom get replaced.

It has to actually go on for a while or have a fairly bad miss for a bit before it'll light a CEL, but a scan tool that's one step above the most basic code reader can check for a misfire count before it'll even set a 'pending" code - that was the tool I used to confirm my issue. Moving the coil with the reported problem to a different cyl. confirmed the spark/coil issue as the problem followed it.

Same year, same engine, so it MIGHT be a similar issue.


P.S. - many use AR104 Autolite plugs for a cheaper "performance" substitute over the stock Platinum plugs. They work better new, but don't last the 100k of platinums (AR103's for a "colder" one for high performance). Spark Plug "stickie" in the duratec section you posted in originally discusses this, used them myself for the experiment to check if plugs were an issue.

2003 2.3 Duratec PZEV: I had the exact same problem for a year and it was solved by diagnostics: cylinder #1 had a bad coil. replaced 4 coils with Motorcraft coils, and 4 new Motorcraft plugs and the miss is gone. Focus has 53K miles now. Thank you for your posts; you led me in the right direction!

 

[Marde]

...
When she shut the engine off I did hear an air like hissing/leaking noise that sounded like it was coming from the front of the engine near the intake...

...Good news though. Just got back from the small independent dealer we bought it from, told them the issue and what we think the problem is. I am buying a new PCV hose, valve and the felpro intake gasket kit and they will install everything...

2003 2.3 Duratec PZEV: I had the exact same problem for a year and it was solved by diagnostics: cylinder #1 had a bad coil. replaced 4 coils with Motorcraft coils, and 4 new Motorcraft plugs and the miss is gone. Focus has 53K miles now. Thank you for your posts; you led me in the right direction!

Your "miss is gone" is great news to hear and very nice of you to share the fix with others; but the OP (Stevenz1inoc) did not share your exact same problem. The OP had a leaking PCV hose. The comment below from the OP was a dead-ringer of a cracked/leaking PCV hose->

"When she shut the engine off I did hear an air like hissing/leaking noise that sounded like it was coming from the front of the engine"

Like the OP, I had that hissing sound immediately after engine off. After removing the intake manifold, I found my PCV hose cracked & leaking. Replacing this hose fixed the hissing sound & the vacuum leak.

Your very low mileage (53K) 2003 Duratec will need a new PCV hose soon due to age (or it has already been replaced).

Good Luck and Congrats for owning such a low mileage 2003 Focus.

 

[Dayna2.3]

Your "miss is gone" is great news to hear and very nice of you to share the fix with others; but the OP (Stevenz1inoc) did not share your exact same problem. The OP had a leaking PCV hose. The comment below from the OP was a dead-ringer of a cracked/leaking PCV hose->

"When she shut the engine off I did hear an air like hissing/leaking noise that sounded like it was coming from the front of the engine"

Like the OP, I had that hissing sound immediately after engine off. After removing the intake manifold, I found my PCV hose cracked & leaking. Replacing this hose fixed the hissing sound & the vacuum leak.

Your very low mileage (53K) 2003 Duratec will need a new PCV hose soon due to age (or it has already been replaced).

Good Luck and Congrats for owning such a low mileage 2003 Focus.

My 2.3L Duratec has not had the PCV hose replaced, but I have it in mind for the next service. My 53K miles are the original owner miles and the coils and plugs that were replaced were the original coils and plugs; I got thirteen (13) years of use out of those! I still get 24mpg in heavy city traffic with new Pirelli P7 tires (eco), yes 205x50x16.

Sorry if this was attached to the wrong post; it was the post before it that I thought it went to. 2003 Focus ZTS PZEV automatic bought new from California in 2003.

 

[Marde]

...Sorry if this was attached to the wrong post; it was the post before it that I thought it went to. 2003 Focus ZTS PZEV automatic bought new from California in 2003.

Whoops, my bad. I wasn't paying attention; now I see what you were doing & also see my mistake. Duh.