zuki1100

Have still not had any luck resolving this issue...but...I think I have made a minor break through. As previously mentioned #1 & #2 plugs (both front) appear normal colour & condition. #3 & #4 plugs are both carbon fouled very badly. Tried replacing the entire distributor and problem is still there so I feel safe to assume it's not an issue with that. Replaced coil back to standard from the Accel Super Stock one I did have...still have the problem. Today I swapped the plug leads over. I did have Bosch Super Sport Inductive Coil type fitted (only 6 months old) and put in an old set from an EA82. I then pulled the plugs out for a check and #3 & #4 plugs have cleaned up nicely to the normal colour after a very short test drive. Could all this problem be from the plug leads??? I will feel very STUPID if I find it's lead related (being such an easy fix) and for some reason my ignition system doesn't like the Bosch Super Sport type. Anyone else reading this had issues with Bosch Super Sport Inductive Core HT Leads?? I'll now be trying a standard set of leads and see what happens...

Have adjusted the air/fuel mixture screw for a mid setting between what I assume is too rich and too lean...I realise this is a bit of a black art to get right without proper equipment and going just by ear. Also swapped over the coil to distributor HT lead and the two rear cylinder leads that were running black plugs. At this stage, run to work and home it stalled once and that was in the morning on the way to work when the choke had opened up and the engine was still quite cold. Seemed to idle around 600-700rpm this morning and about 800rpm on the way home. With a bit of WOT the idle improved, up to 900-1000rpm for a period of time. I'm going to try making the mixture a bit richer and see if that improves the idle and also adjust the choke to stay on a bit longer. Will update again once I've done a few runs to work and back

Changed the plugs about 12 months ago, they are the NGK V-Groove type. Interesting you say that...the front plugs both sides are a brownish colour which suggests they are OK ad the the back plugs, both sides are black (carboned). It's an electronic distributor, how do I check this is functioning correctly? Any test/check I can do? Cleaned cap contacts, they are passable, can't get a replacement easily and a new one from Subaru is $150.00 and 1 week ex-Japan. Brand new Rotor put in 2 days ago. Leads are Bosch Super Sport from memory, they were new about 12 months ago, same time as plugs. Yes I have a manual. You think it's worth while changing out the plugs & leads for a spare set I have? I suppose it would be good comparison.

A bit more to this story... Have found the rough idle/stall usually occurs after the choke has disengaged, but will also happen during acceleration (not always WOT) and not all the time. Sometimes, however, WOT will also correct the problem and the idle will return to normal afterwards. So I'm perplexed as to what could be causing this...some thoughts... -Intermittent vacuum leak? -Intermittent problem with the carb idle circuit (although have tried two different carbs with the same problem...coincidence??) -Electrical problem? Battery shows 13.89V at idle which is about right for a normal charge. -Throttle linkage problem, not fully returning to fully closed position? At idle I have noticed a loudish sucking sound at the front of the carb where the power steering pump is. But the idle will be normal while this sound is there. Might try changing back to my original carb and see if the problem is worse/better. Very keen for some more thoughts from everyone out there and trouble shooting.

Cool, I'll check that out. Battery appears to be OK, but I suppose you never know. Have found also that if it goes into the stall situation while still moving like when slowing down for intersection and I release the clutch in gear to restart the motor, the rough idle is immediately gone and revs go back to normal. What do you suppose is happening when I start the car in this way that makes this problem go away?

No, just swapped the carb directly over. I'm wanting to think it's not a carb issue as the problem happened on both carbs, surely the same issue wouldn't be evident on both carbs? Went out last night to get a bottle of wine, car ran fine. Stopped and got the wine, went back to the car, started and the idle was stumbling again, almost stalling but came right within 1-2mins of driving. I'm planning now to clean up all the valves and manifold of non-essential items, so remove the EGR, plug non essential vacuum lines and clean the PCV valve.

A little update, have replaced fuel filter this morning to at least eliminate that as a potential problem, only cost $5.00 and I cut the old one open, was very dirty and had bits of "stuff" in the bottom of it.

I've read a lot of info here about people experiencing similar problems, however I haven't seen anyone mention an observation that I made...which leads me to believe I may have a unique problem??? About 2 months ago I was climbing a hill (4wding) and when I got to the top the idle was very rough. I was hitting WOT. From there it wouldn't idle at all and would stall. Drove home fine, the engine would run fine at cruising speed but when I came to stop it would idle rough and stall. Ran fine after that for a few weeks then did it again heading to work one day and didn't come right at all. So I swapped over my carb for one off an EA82 thinking that will fix the issue, but it didn't. Was out yesterday and found that the car runs fine if you DON'T give it full throttle. As soon as you go WOT, when you come to a stop immediately after the idle is rough and the engine eventually stalls. Have found in doing this if I engage the Air Con, this helps keep the revs up if it's threatening to stall...but only works sometimes as when it's about to stall (I assume) it's not generating enough vacuum to engage the AC idle up solenoid. So I'm quite sure this issue comes about right after going WOT. Something else to add...while out yesterday I went WOT, the idle went very low and would keep stalling every time I came to a stop, did this for 5 or so mins then while coming up to stop it did it again, I crash started it (using the engine to to restart while still moving) and the idle came back to normal. Cold starting is fine, electric choke works normally and well. Engine seems to idle fine after warm up. Sorry for the long wordy post...just trying to offer as much info as possible. Look forward to some idea's and advice on where to look.