'07 Liberty GT-B severe hesitation / Misfire
Posted: Mon May 18, 2015 11:52 pm
Hi all.
Done a search and gone through numerous threads each with different endings regarding similar/same problems that I'm experiencing.
I thought I'd create a new thread in order to, with all of your help, build a comprehensive check list for myself and others who may have the same issue!
Car:
Libery GT spec B 2.5T 6-speed manual 2007 model. Full Subaru service history. 130,000KM
No engine CEL on dashboard
Symptoms:
1) While stationary engine warm, holding the revs up to around 1500RPM, the car will briefly sound like it is slightly missing & the engine will shake more than usual (noticeable in cabin), then regulate itself after 2-3 seconds. If you back off the gas to idle, and repeate it a few times, it'll do it again. Probably 1 in 5 times results in the aforementioned Misfire like symptom. It's a little tricky to get it to show this symptom.
2) while driving in stop start traffic, engine warm, the car will occasionally "bunny hop" or shudder. it is sometimes quite violent, almost undrivable, sometimes it is more gentle and noticeable. This occurs when the car overruns to 1300/1500 rpm, slowing down naturally, then accelerating. It happens when you accelerate from slow speeds around 1500 rpm essentially. Think of someone falling off a clutch when learning to drive. FYI I am not using the clutch at all in this scenario. This issue seems worse in Intellegent mode, and slightly better in sport mode.
3) hesitation on boost. When going to WOT from 2500-ish rpm, the car will climb but hesitate and stumble as it makes boost. It doesn't come on smooth. Third gear seems smoother than second. If you go to WOT from say 4000 RPM, it is less noticeable and seems to come on strong.
Thoughts
1) could be one issue or a bunch of small issues.
Fix list.
1) ordered 2 x OCV solenoids for Intake VVT
2) ordered 4 x OEM spark plugs
3) remove screen / filter from drivers side, engine head side banjo bolts.
What else could it be?
1) EGR needs cleaning?
2) coilpacks?
3) Blocked head side banjo bolt for Passenger solenoid oil feed?
I'm thinking of pulling the timing belt off to remove the screen from the passenger side solenoid oil feed. The last thing I want to do is replace a solenoid and have it fail again due to starvation!
Do the solenoids fail over time or fail due to oil starvation?
Thoughts?
Please feel free to add your known / potential fixes and I will tick them off one-by-one and see if it resolves the issue.
Thank you all in advance for any help you can provide.
Done a search and gone through numerous threads each with different endings regarding similar/same problems that I'm experiencing.
I thought I'd create a new thread in order to, with all of your help, build a comprehensive check list for myself and others who may have the same issue!
Car:
Libery GT spec B 2.5T 6-speed manual 2007 model. Full Subaru service history. 130,000KM
No engine CEL on dashboard
Symptoms:
1) While stationary engine warm, holding the revs up to around 1500RPM, the car will briefly sound like it is slightly missing & the engine will shake more than usual (noticeable in cabin), then regulate itself after 2-3 seconds. If you back off the gas to idle, and repeate it a few times, it'll do it again. Probably 1 in 5 times results in the aforementioned Misfire like symptom. It's a little tricky to get it to show this symptom.
2) while driving in stop start traffic, engine warm, the car will occasionally "bunny hop" or shudder. it is sometimes quite violent, almost undrivable, sometimes it is more gentle and noticeable. This occurs when the car overruns to 1300/1500 rpm, slowing down naturally, then accelerating. It happens when you accelerate from slow speeds around 1500 rpm essentially. Think of someone falling off a clutch when learning to drive. FYI I am not using the clutch at all in this scenario. This issue seems worse in Intellegent mode, and slightly better in sport mode.
3) hesitation on boost. When going to WOT from 2500-ish rpm, the car will climb but hesitate and stumble as it makes boost. It doesn't come on smooth. Third gear seems smoother than second. If you go to WOT from say 4000 RPM, it is less noticeable and seems to come on strong.
Thoughts
1) could be one issue or a bunch of small issues.
Fix list.
1) ordered 2 x OCV solenoids for Intake VVT
2) ordered 4 x OEM spark plugs
3) remove screen / filter from drivers side, engine head side banjo bolts.
What else could it be?
1) EGR needs cleaning?
2) coilpacks?
3) Blocked head side banjo bolt for Passenger solenoid oil feed?
I'm thinking of pulling the timing belt off to remove the screen from the passenger side solenoid oil feed. The last thing I want to do is replace a solenoid and have it fail again due to starvation!
Do the solenoids fail over time or fail due to oil starvation?
Thoughts?
Please feel free to add your known / potential fixes and I will tick them off one-by-one and see if it resolves the issue.
Thank you all in advance for any help you can provide.