 |
|
|
|
Next: Joined the Nitrogen tire club... Goodbye (!)
|
| Author |
Message |
External
Since: Aug 23, 2004
Posts: 44
|
(Msg. 1) Posted: Tue Jan 01, 2008 1:30 am
Post subject: EJ25 Liberty RX (Legacy) hiccups at cruise
Archived from groups: alt>autos>subaru (more info?)
|
|
|
Folk,
This has been a problem on and off for a while now. It came on
again a couple of Km after a refill at a station we don't normally
go to.
The engine behaves fine under acceleration, but within a few seconds
of cruise, will start to hiccup, losing power totally for half a
second, and repeat that irregularly *every few seconds*. It's quite
jerky - annoying almost to the point of being undriveable, and I'm
also worried that it might be doing damage - pinking? If you
alternate between slight acceleration and lifting the foot, it
doesn't seem to happen - until you stop changing speed for ~2 secs.
The acceleration response is fine, so I don't think it's the fuel
filter.
I suspect that the ECU has detected cruise, and is experimenting to
find how much it can lean out the mix... but is going too far. I
suspect the O2 sensor. Given that this is expensive to replace, is
it possible/easy to expect to *try* a replacement before committing
to paying for it? Apart from just replacing it anyhow, is there any
other option?
Has anyone else had this symptom or can suggest an alternate cause?
Clifford Heath. |
|
| Back to top |
|
 | |
External
Since: Dec 22, 2007
Posts: 51
|
(Msg. 2) Posted: Tue Jan 01, 2008 1:30 am
Post subject: Re: EJ25 Liberty RX (Legacy) hiccups at cruise [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)
|
|
|
Bad gas? Finish the tank fill with gas you know is good and add a gas
line antifreeze to remove water and see what hapens
On Dec 31, 8:45 pm, Clifford Heath <n....TakeThisOut@spam.please.net> wrote:
> Folk,
>
> This has been a problem on and off for a while now. It came on
> again a couple of Km after a refill at a station we don't normally
> go to.
>
> The engine behaves fine under acceleration, but within a few seconds
> of cruise, will start to hiccup, losing power totally for half a
> second, and repeat that irregularly *every few seconds*. It's quite
> jerky - annoying almost to the point of being undriveable, and I'm
> also worried that it might be doing damage - pinking? If you
> alternate between slight acceleration and lifting the foot, it
> doesn't seem to happen - until you stop changing speed for ~2 secs.
> The acceleration response is fine, so I don't think it's the fuel
> filter.
>
> I suspect that the ECU has detected cruise, and is experimenting to
> find how much it can lean out the mix... but is going too far. I
> suspect the O2 sensor. Given that this is expensive to replace, is
> it possible/easy to expect to *try* a replacement before committing
> to paying for it? Apart from just replacing it anyhow, is there any
> other option?
>
> Has anyone else had this symptom or can suggest an alternate cause?
>
> Clifford Heath. |
|
| Back to top |
|
| |
External
Since: Jan 01, 2008
Posts: 1
|
(Msg. 3) Posted: Tue Jan 01, 2008 1:30 am
Post subject: Re: EJ25 Liberty RX (Legacy) hiccups at cruise [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)
|
|
|
bigjimpack.RemoveThis@gmail.com wrote:
> Bad gas? Finish the tank fill with gas you know is good and add a gas
> line antifreeze to remove water and see what hapens
Don't think so - we've been through 5-10 tanks of gas
from our regular sources since it started happening
again recently. Also used injector cleaner, which does
seem to help a bit, maybe. We only ever buy premium
gas in any case. Dirty gas will foul the filter and
cause problems on acceleration, but this is at cruise.
Clifford Heath. >> Stay informed about: EJ25 Liberty RX (Legacy) hiccups at cruise |
|
| Back to top |
|
| |
External
Since: May 04, 2004
Posts: 311
|
(Msg. 4) Posted: Tue Jan 01, 2008 2:18 am
Post subject: Re: EJ25 Liberty RX (Legacy) hiccups at cruise [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)
|
|
|
Clifford Heath <no.DeleteThis@spam.please.net> writes:
> Folk,
>
> This has been a problem on and off for a while now. It came on
> again a couple of Km after a refill at a station we don't normally
> go to.
>
> The engine behaves fine under acceleration, but within a few seconds
> of cruise, will start to hiccup, losing power totally for half a
> second, and repeat that irregularly *every few seconds*. It's quite
> jerky - annoying almost to the point of being undriveable, and I'm
> also worried that it might be doing damage - pinking? If you
> alternate between slight acceleration and lifting the foot, it
> doesn't seem to happen - until you stop changing speed for ~2 secs.
> The acceleration response is fine, so I don't think it's the fuel
> filter.
>
> I suspect that the ECU has detected cruise, and is experimenting to
> find how much it can lean out the mix... but is going too far. I
> suspect the O2 sensor. Given that this is expensive to replace, is
> it possible/easy to expect to *try* a replacement before committing
> to paying for it? Apart from just replacing it anyhow, is there any
> other option?
>
> Has anyone else had this symptom or can suggest an alternate cause?
>
> Clifford Heath.
o2 sensor is a frequently mentioned item that explains all sorts of
strange driveability problems.
My own experience, however, was that a timing belt replacement caused
me hell like you're experiencing. Not exactly the same, though. My
stumbles and bucks were intermittent and on accelleration (reliably at
4k rpm when it happened--and maintaining 4k rpm as a cruise speed
would exhibit bucking that was annoying, but not undriveable) and on
deceleration around 1250 rpm. Turns out a bad timing belt tensioner
led to a flattened a tooth on a new timing belt when was slipping
periodically by one tooth, causing my woes.
--
Todd H.
2001 Legacy Outback Wagon, 2.5L H-4
Chicago, Illinois USA >> Stay informed about: EJ25 Liberty RX (Legacy) hiccups at cruise |
|
| Back to top |
|
| |
External
Since: Apr 12, 2007
Posts: 76
|
(Msg. 5) Posted: Tue Jan 01, 2008 6:50 pm
Post subject: Re: EJ25 Liberty RX (Legacy) hiccups at cruise [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)
|
|
|
Hi:
I had driveability issues recently caused by a bad O2 sensor. It was more
prevelant at startup when cold than at cruising speed, but it did sometimes
happen at cruising speed with a warm engine. Usually it happened when I
lifed up off of the gas. It was as you describe, though, bucking and
surging. And it was intermittent. And the Check Engine Light wasn't
triggered as you might expect.
Initially it was diagnosed as an ignition coil - later, correctly identified
as a bad O2 sensor. FWIW... Good luck!
--
Fred Boer - Amateur Access Enthusiast
Interests: Library software / Z39.50 / Web Services
Freeware Small Library Application available here:
http://www3.sympatico.ca/lornarourke/
"Clifford Heath" <no.TakeThisOut@spam.please.net> wrote in message
news:47799b23$0$26179$afc38c87@news.optusnet.com.au...
> Folk,
>
> This has been a problem on and off for a while now. It came on
> again a couple of Km after a refill at a station we don't normally
> go to.
>
> The engine behaves fine under acceleration, but within a few seconds
> of cruise, will start to hiccup, losing power totally for half a
> second, and repeat that irregularly *every few seconds*. It's quite
> jerky - annoying almost to the point of being undriveable, and I'm
> also worried that it might be doing damage - pinking? If you
> alternate between slight acceleration and lifting the foot, it
> doesn't seem to happen - until you stop changing speed for ~2 secs.
> The acceleration response is fine, so I don't think it's the fuel
> filter.
>
> I suspect that the ECU has detected cruise, and is experimenting to
> find how much it can lean out the mix... but is going too far. I
> suspect the O2 sensor. Given that this is expensive to replace, is
> it possible/easy to expect to *try* a replacement before committing
> to paying for it? Apart from just replacing it anyhow, is there any
> other option?
>
> Has anyone else had this symptom or can suggest an alternate cause?
>
> Clifford Heath. >> Stay informed about: EJ25 Liberty RX (Legacy) hiccups at cruise |
|
| Back to top |
|
| |
External
Since: Aug 23, 2004
Posts: 44
|
(Msg. 6) Posted: Wed Jan 02, 2008 1:30 am
Post subject: Re: EJ25 Liberty RX (Legacy) hiccups at cruise [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)
|
|
|
Todd H. wrote:
> My own experience, however, was that a timing belt replacement caused
> ... Turns out a bad timing belt tensioner
> led to a flattened a tooth on a new timing belt when was slipping
> periodically by one tooth, causing my woes.
That's good info Todd. I'm trying to understand exactly what the
effect was caused by. Surely if the timing belt slips the timing
will be off permanently? Or was it just sending a spasm down the
belt by jumping on the tensioner only?
Clifford Heath. >> Stay informed about: EJ25 Liberty RX (Legacy) hiccups at cruise |
|
| Back to top |
|
| |
External
Since: May 04, 2004
Posts: 311
|
(Msg. 7) Posted: Wed Jan 02, 2008 1:30 am
Post subject: Re: EJ25 Liberty RX (Legacy) hiccups at cruise [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)
|
|
|
Clifford Heath <no.RemoveThis@spam.please.net> writes:
> Todd H. wrote:
> > My own experience, however, was that a timing belt replacement caused
> > ... Turns out a bad timing belt tensioner
> > led to a flattened a tooth on a new timing belt when was slipping
> > periodically by one tooth, causing my woes.
>
> That's good info Todd. I'm trying to understand exactly what the
> effect was caused by. Surely if the timing belt slips the timing
> will be off permanently? Or was it just sending a spasm down the
> belt by jumping on the tensioner only?
It seemed like it was slipping back and forth, and the ECU was able to
adjust to compensate...but only to a point.
Took nearly all of 2007 to get to the bottom of it.
--
Todd H.
2001 Legacy Outback Wagon, 2.5L H-4
Chicago, Illinois USA >> Stay informed about: EJ25 Liberty RX (Legacy) hiccups at cruise |
|
| Back to top |
|
| |
External
Since: Aug 23, 2004
Posts: 44
|
(Msg. 8) Posted: Wed Jan 02, 2008 1:30 am
Post subject: Re: EJ25 Liberty RX (Legacy) hiccups at cruise [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)
|
|
|
Todd H. wrote:
> It seemed like it was slipping back and forth, and the ECU was able to
> adjust to compensate...but only to a point.
Sounds like it might have been climbing up on top of the tension
idler, then dropping back into the notch, and causing tension
changes that advance both cams (or retard - is it on the trailing
or leading side?). I guess a tight/failed idler bearing will do that.
I need to do the cam cover gaskets anyhow, maybe the idler is easy
to do at the same time. Tackle the O2 sensor only if that doesn't
cure it.
Clifford Heath. >> Stay informed about: EJ25 Liberty RX (Legacy) hiccups at cruise |
|
| Back to top |
|
| |
External
Since: May 04, 2004
Posts: 311
|
(Msg. 9) Posted: Wed Jan 02, 2008 10:43 am
Post subject: Re: EJ25 Liberty RX (Legacy) hiccups at cruise [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)
|
|
|
Clifford Heath <no.TakeThisOut@spam.please.net> writes:
> Todd H. wrote:
> > It seemed like it was slipping back and forth, and the ECU was able to
> > adjust to compensate...but only to a point.
>
> Sounds like it might have been climbing up on top of the tension
> idler, then dropping back into the notch, and causing tension
> changes that advance both cams (or retard - is it on the trailing
> or leading side?). I guess a tight/failed idler bearing will do
> that.
My situation was caused by a defective (brand new, OEM, Subaru) timing
belt tensioner not pumping up to tension on a brand new belt after the
engine had been hand turns the designated 3 or whatever times
(specified in a TSB on the issue) when a new belt was isntalled. A
tooth on the belt was flattened in this initial startup sequence and
wasn't found until months later.
--
Todd H.
2001 Legacy Outback Wagon, 2.5L H-4
Chicago, Illinois USA >> Stay informed about: EJ25 Liberty RX (Legacy) hiccups at cruise |
|
| Back to top |
|
| |
Joined: May 23, 2008
Posts: 1
|
(Msg. 10) Posted: Fri May 23, 2008 10:34 pm
Post subject: Re: EJ25 Liberty RX (Legacy) hiccups at cruise [Login to view extended thread Info.]
|
|
|
I have been having the exact same problem with my 2000 Outback L 2.5l. A few times my AT Oil Temp light flashed and it shifted hard till I restarted. I also have gotten a intermittent p0122 code for the tps, but the chk eng light only comes on 2% of the time. I have changed it twice with no change. Did you ever fix the issue? Thanks Much in advance! >> Stay informed about: EJ25 Liberty RX (Legacy) hiccups at cruise |
|
| Back to top |
|
| |
|
You can post new topics in this forum
You can reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
|
|
|
|
|
|
|
FAQ
Profile
Private Messages
Log in
