6 replies to this topic

[02_Liberty_RX]

Hey guys, just recently my Gen 3 Liberty 2.5 has started to misfire (I think). It is worst when I am accelerating and its over 2500 rpm. It shakes the car and wont stop until I change gears or release the accelerator pedal. Really recently it has also had a miss when I'm in neutral waiting at lights. The car will shake when it misses and I'm worried it will stop on me. Is there something I can do or do I need to get it sent to a mechanic. Is this a common problem with an easy solution that I can do myself at home? I've tried to explain it as well as I can, any help would be much appreciated. If there are any other details that I need to mention to clarify what Im trying to say, by all means ask.

 

Any help would be much appreciated,

Thanks guys

[02_Liberty_RX]

Hey guys I think it might be getting worse, its missing in neutral a lot more now. Does anyone have any idea of what it could be or things I could check to see if they are causing the problems?

 

Cheers

[Jimbo]

First place to start would be the ignition leads. Have the car running, remove and replace each one until you find the culprit. If it's not the leads, spark plugs are the next things to check/replace.

[duncanm]

check your spark plug leads are ok - measure them with a multimeter - I think they should be around 10k .

 

I found my 2.5 leads went bad when I noticed one was arcing from the coilpack out of the plug boots to the manifold whilst idling.

natch jimbo.

 

EDIT - occassional stutter whilst idling is a pretty good sign its ignition problem.

[RX25SE]

Another thing to note is its common ignition problems to be most noticeable when under load (accelerating).

 

As above, check resistance of ignition leads. If one is faulty it would be worth replacing the set.

 

If it's not the leads then the next most likely culprit is the coil itself. You can measure the resistance of the two coil circuits (primary - battery side & secondary - spark plug side)

 

 

Primary: 0.73 ohms plus or minus 10%

Secondary: 12.8K ohms (12800) ohms plus or minus 15%

 

 

The primary's are tested between terminal 1 & 2 and terminals 2 & 4.

When looking at the coil pack, terminal 1 is extreme right.

 

Secondary's are each end (opposite) of the coil.

[02_Liberty_RX]

Thanks for the replies guys, 

 

If I were to buy some leads, is there any brand in particular that is better or has worked better with Subarus (in particular 2002 gen 3 Liberty 2.5 liter motor)?

 

If it were the coil, how much are they if it needed to be replaced?

 

Cheers

[duncanm]

coil - wreckers - pick n payless charges about $50.

 

any leads are probably ok. 

 

btw - I just checked the FSM, lead resistance should be 

1. 5.6 - 10.6k
2. 7.3 - 13.7k
3. 5.9 - 11.1k
4. 7.3 - 13.7k

these are very precise -- I'd just be making sure they're all between 5 and 15k