Two Part questions: Part One When I brought my new rig back to town I started off ok then had about a half hour drive on the freeway to my sister's place and noticed that the Sambar had a stumble/ surge to it that happened randomly but seemed worse under load. I thought maybe it just needed a tune up. I have to take a ferry to get to the Island were I live then it's a hour drive to the city were I live, at about the half way point there was a moderate climb with a stop light at the bottom and as I got into fourth gear it was stumbling pretty bad but holding speed. At that point the red catalytic converter warning light came on and has stayed on since. After I got home I started checking things out under the " hood" and the air filter was new so crossed that off the list. I found a loose vacuum line [see part two below] and plugged it off. That made no difference, so I went shopping for some new spark plugs. I thought that the NGK IX Iridium's [part # BKR6EIX]looked like the would do the trick. When I was taking out the old plugs I discovered a couple of things: 1. the #4 plug had the porcelain cracked lenghtwise in two places and 2. it was one heat range cooler xxxx5xx. I took for a burn up the street after installing the new plugs and it has cured the stumble/ surge but I still have the Cat warning light on. It will pull good in 5th gear even if I bog it down at low speed and it revs freely/ quickly in first so I don't think that the cat is plugged. No dought that it must have got a pretty good dose of unburnt fuel from #4 cylinder on the trip home though causing it to heat up. I am wondering if the Cat warning light is like the "check engine" light were it keeps the problem in the OBD until it's reset. Then it will go out. Any thought's? Part Two Remember the loose vacuum line from above? Well I looked high and low over every square inch of the engine compartment and could not find a port or hose that it could be from. So I plugged it off thinking that it was part of my problems above. I had checked out the 4wd system and the diff lock when first got home and they both worked perfect, with the indicator lights coming on and going out when released. After working on the engine [plugging the vacuum line] I by chance tryed to engage the 4wd and no go - no 4wd light and likewise for the diff lock. I thought that I was having some kind of goofy electrical problem that was causing it to act up but during the day I got to thinking that the only thing that had been changed was the vacuum line got capped off. So I opened up the engine and pulled the cap off the line and it still had vacuum in it after the truck not been run for some time. With the vacuum line now uncapped - the way it came to me I started up the truck and low and behold the 4wd and diff lock both worked again. If you look in my photo album here http://www.minitrucktalk.com/galleries/showphoto.php/photo/668 you can see the loose vacuum line right beside the "N" in Japan on the casting. Another shot here http://www.minitrucktalk.com/galleries/showphoto.php/photo/669 So my question is: Where was the line hooked up to when the truck left the factory? Seems highly unlikely that Subaru would have just run the line to "nowhere". Judging by the way the 4wd/ diff lock system works it needs just a filtered air source [like the engine side of the filter element] or? Thoughts?
I dont have any supercharged units in stock at the moment. The carb'd one here does not have that hose, but it has another that is plugged. I wonder if thats the vent for the difflock. Up high so it doesnt take in water. But if its plugged, the solenoid wont move, therefore not engaging. But I wouldnt think that would affect the 4WD unless its the transfer case vent.
Thanks for reply. The other end of hose goes to a solenoid that has two ports, it is mounted just in front of the engine cover. The other hose goes from the solenoid to a port by the supercharger [might be the diff lock]. Both hoses look factory - they have marking on them.
Yeah, it seems that may be the atmospheric vent for the 4WD actuator. If its plugged, there is no where for the air to go so it wont engage. Makes sense I guess. (I am no mechanic) I dont know if having it behind the filter will cause any issues or not (Under vaccuum).
I know this is an ancient thread, but did you ever get an answer to this? I just removed my engine for a clutch replacement, and I am trying to figure out where this hose goes.
