Major Idle Issue - 2004 Liberty GT

[NDARYD]

Hi all,

I am currently having a major issue with my 2004 Liberty GT (Auto). I have owned it for about 6 months now and has 100,000km and full service history.

The car idles very rough in low speeds and stationary position and the revs will drop until the car stalls but when I am driving the car (over 20km/h it feels fine). It is most evident in R, N & D but also evident in P.

I took my car to the mechanics last week to have a look at it and also do the major service so the following work has been done recently:

- Engine Oil, Oil Filter, Trans Oil (around 8 weeks ago) I performed this work myself - car had no issues.
- Fuel Filter (which is inside the fuel pump under rear seats) (around 2 weeks ago) I performed this work myself - car had no issues.
- Washed my car and quickly washed the engine bay (water only) - just over 1 week ago - drove the car around 50km distance that day with no issues and then the idle fault began the next day - Could this be the cause?
- Timing Belt Kit (last week when I took it to the mechanics for major service and to find the idle fault) - he also changed the alternator belt (it was worn), sparks plugs and checked the coils which were fine to eliminate the idle problem.

The mechanic since then has given up saying he cannot find what the fault is. There is no ECL on and there are no Error Codes showing up. He mentioned when he removed the Temp Sensor that the idles would run smoothly so he was almost certain this was the fault, ordered a brand new replacement from Subaru and replaced it only to find the same issue was happening so he gave up (lucky he didn't charge me for the fault finding).

Would anyone here have a clue what could be the issue or how to eliminate the fault?

[swingn]

Does your mechanic have the tools to adjust ideal settings? Could just be something as simple as that. We actually had that problem with one of our BMW's.

Alternatively, this is a bit of a long shot, has the car been tuned? I know some members have had similar issues as you've described which was actually caused by the tune.

[Robbks]

Blocked AVCS solenoid filters

search and you will find
viewtopic.php?f=17&t=13374&hilit=idle

[NDARYD]

swingn - I am not sure if he has the tools to adjust ideal settings - I will ask him this afternoon and I don't think the car has been tuned.

Robbks - I will read through this discussion now and see what I can check out.

I did forget to mention the 02 sensor was changed just before I bought the car (when I went to inspect the car the ECL was on and cruise control flashing) - could this maybe be faulty again? It is still under warranty.

[swingn]

I did forget to mention the 02 sensor was changed just before I bought the car (when I went to inspect the car the ECL was on and cruise control flashing) - could this maybe be faulty again? It is still under warranty.

If the O2 Sensor went bad again, you'd get the cruise control flashing again.

[PHAT GT]

the car could have has a hose pop of with will cause a vacuum leak causing the low to no idle problems

[NDARYD]

I have read on the forum that the Cruise Control and ECL does NOT necessarily have to come on if the o2 Sensor was faulty.

I will check tomorrow for a vacuum leak, but assume the mechanic would have checked this.

[HOL71]

How's this problem going? I had a very similar issue with a faulty rear O2 sensor which was sending inaccurate data but not throwing a code.

[UrbanGTB]

Had a similar problem, found out in the end it was due to crappy fuel from a particular servo even though it was BP 98, went to a different location and the car runs a hell of a lot better. Run it low on fuel and get a tank from somewhere else to rule it out

[NDARYD]

Was not the Rear o2 Sensor (this was replaced 6 months ago) and was not due to poor quality fuel.

I had Subaru perform a Diagnostic Test on my car and they found some of the timing lines were clogged up, they simply cleaned it up and the car runs perfectly now - less than an hour labour all up to locate the issue and resolve it.

If anyone has a similar problem I suggest taking it to Subaru as they can do a scan and diagnostic test to locate the exact issue as my local mechanic spent days on it without being able to locate the issue but Subaru found it very easily.