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'88 Subaru: Where is vapor separator?

Have an '88 Subaru DL Stationwagon automatic; trying to get it back on the road. Trying to replace the fuel vapor separator and not sure how to get to it. Do I have to remove the interior vinyl trim panel in the cargo area on the passenger side (that runs from the rear door back to the tailgate, covering the wheelwell), and if so, how big a pain is this? How about putting the panel back on? Or do I dismantle something underneath by the gas tank to get to the darn thing? Nothing that looks like the new vapor separator I ordered through the Subaru dealership is visible under the car. HELP!

The vapor seperator is located under the vehicle, either above or near the gas tank.


WHERE IS IT? Since it can’t be seen, how the _ _ _ _ do I get to it/find it? As my question states, I need to know what I need to do to get to this part!!!

YOu need to lose the attitude if you want help.

Are you entitled, I noticed another post of you demanding a shop to tell you where something was.

An excellent board for older Subaru questions is

Drop the attitude though, it will get you no where fast.

Have you considered buying a Service Manual"?? Be sure to get the “Emissions Controls” supplement…

I’m the original poster. I’m very frustrated trying to fix a problem I believe will get my older vehicle back on the road. Way back when this all started I didn’t have a regular garage/ mechanic to take it to because the mech. I had used for a number of years had told me when it had broken down on the interstate when the water pump went out not to have it towed to him because he wouldn’t even look at it for three weeks- too busy. I’d always tried to be pleasant and friendly, and grateful for his work, paid promptly, and was patient with any delays. When he said don’t bring it here, it seemed pretty clear he didn’t want to do any more work on my car, so I went to another local garage who put in the water pump and sent my car home with a new starting problem. I dascovered several days, and several inconvenient strandings later, they hadn’t tightened the battery cables. Next time I needed a garage, took it back to the same place where they fixed the problem and again sent me home with a starting problem (loose battery cables) which this time I recognized immediately. Resolved never to go back to a garage that was that careless twice, even after they were reminded of their oversight the first time. Back to the current issue: the diagnosis for this problem was given to me years ago by an employer who had been a longtime Subaru owner and gave me several very good and accurate predictions about serice problems that would come up with my car and the approximate milage at which these problems would occur. My car was 100,000 miles overdue for a plugged rear “in line fuel filter” as Joe described it to me. The car died with electrical problems which I did not have the money at the time to pursue fixing. Eventually I spent several hundred dollars on a new battery, rebuilt alternator, new distributor cap, plugs and wires, all of which I installed myself. It was my years of listening to Car Talk which had given me the courage and confidence to start doing more than just changing a flat on my own vehicle.
The engine cranked, but if it fired up it would only be for a second before cutting out again. During my attempts to get the car started, I burned out the starter and had to install a remanufactured one. At that point I paid to tow the car to a garage to diagnose the starting problem and fix it. I suspected the “rear fuel filter” was the problem, but the Haynes repair manuel didn’t list such a creature. I told the garage everything I had done, what the car was doing when it died, and what I believed the solution was. MANY months later the owner of the garage called, said they couldn’t figure out what was wrong and told me to pick the car up. Another mechanic with his own shop very confidently told me he could get my car running, so I had it towed there. I left my Haynes manuel with the car in case that might be of any help to him. More than six months later, he finally confessed he had no idea how to get the car started and suggested I pick it up. For the third time, I paid a tow truck to haul the car, this time back home, but without my Haynes manuel which the garage had lost, and with a burned out starter, again. No one had bothered to switch out the vapor separator, which is the only “fuel filter” back by the gas tank which I have been able to ascertain. Several years have passed since then with the car sitting.
I am now desperate to get this car back on the road because my '71 pickup truck now needs a new engine, which I can’t afford and I am without transportation. I live in the country and have to rely on cadged rides, hitchhiking, and borrowing vehicles to get to work, to the grocery store, and to the farm supply store. Needless to say, time is an issue. I have spent several weeks getting a new Haynes manuel (way more difficult than it should have been), figuring out what part (vapor separator), was probably needed and get it ordered and picked up, picking up and installing a rebuilt starter and a fuel filter, and now trying to find out where to put the vapor separator.
This is not rocket science, it is definitely a DIY possible fix; all I’m asking is whether I have to disassemble the interior vinyl trim panel or something under the car to get to the part I’m switching out. I wouldn’t have asked the question here if it wasn’t hosted by Car Talk, the mecca of DIYers.

Given the size of the part (evaporative canister); will it fit in the space between the sheet metal for the fender and the interior panel? If yes, I’d guess that the canister is located near the fuel filler and you access it via removal of the interior panel, or dropping the fuel tank. If you remove the interior panel perhaps you can see something and then know how to proceed.

From the lack of responses it seems you are in “unknown” territory for many of us, and certainly myself. If you can find a junkyard with a similar year Subaru wagon perhaps you can tear apart the back of it and get some answers on where the part is and how to change it out.

What type of problem is this defective vapor seperator causing? I now suspect your diagnostic process (someone who can predict when a car will “go down” with a specific problem is you guidiance, pretty scary), what I mean is I hope you don’t expect replacing this vapor seperator to allow a non-starting vehicle to start.

Yes, as a matter of fact I have high hopes that replacing this filter will be the magic bullet to get my car to start. My info source was a fellow who had years of experience with these Subaru stationwagons (he, his wife, and I think several of his children drove Subarus). Every time I had to call in to let him know I’d be late to work because of a problem with the car, he’d ask me for a few details and then accurately predict what the problem and fix were. (He ran a restaurant; not a mechanic.) It was nice being able to tell the mechanic “I think it’s thus and such”, and be right. One day I came off a mountain from a long hike with barely enough time to get home, change and get to work on time, and the car died shortly after leaving the parking lot. Had to call AAA for help, and then call Joe to tell him I didn’t know how late I’d be, stranded on the side of the road. I told him what happened when the car died and he asked how many miles it had on it . 115,000 miles. Had I ever changed the timing belt? No. He said ‘It’s the timing belt, they break at about 70,000 miles. I’m surprised your’s lasted this long.’ And he was right. Approximately 70,000 miles later, right on schedule, that timing belt broke and had to be replaced again. He was right about all his predictions, so I have no doubt this filter (if it is indeed the “rear in-line fuel filter” he described) needs replacing. If anybody has any other brainstorms on why it won’t start after all the needed and recommended electrical fixes, I’m glad to hear any ideas. Thanks.

Here is the procedure to replace the liquid vapor separator.

Remove right trim panel from luggage compartment.
Remove hose protector.
Remove fuel separator and bracket as a unit.
Disconnect evaporation hose from pipe connected to bracket.
Remove fuel separator from bracket.
Disconnect hose from separator.

Reverse removal procedures and observe the following:
Install the hose between fuel separator and pipe until it stops against nipple on the separator side and push the other end up to the marked position on the pipe side.
Install fuel separator on the bracket so that the pipe can run through the relieved section of the separator.
Install the evaporation tube 15 to 20 mm (0.59 to 0.79 in) onto the pipe on the bracket. Install clamps so they do not touch any other hoses.

I’ve got news for you - no mechanic is going to turn down work that he will get paid promptly for unless:

  1. He knows that he cannot solve the problem
  2. He knows that he cannot fix the problem fast enough to keep the customer happy.

Isn’t it entirely possible that he was being honest when he told you he couldn’t get to it for three weeks? Some good mechanics are seriously overloaded with work, and maybe he knew that he couldn’t possibly fix your car fast enough to make you happy, and therefore decided the best solution was for you to take it elsewhere?

I suspect that was the case or you had done something to seriously annoy him before to the point that he just didn’t want to deal with you anymore. Either one is possible, but I don’t see any reason to believe that he was doing anything wrong for advising you to go somewhere else.

Its understandable to be frustrated, but all your posts have come across with a serious attitude that isn’t helping…

Have you measured the fuel pressure when you’re trying to start the car to make sure that you aren’t getting good fuel pressure? I don’t see any references in your posts to say that you have checked that… although I believe a mechanic would have checked that if he had your car in the shop for months…

I’d test right after the pump, make sure you’re good then, then after the fuel filter, and if those both test fine, then check after the fuel pressure regulator.

What I see so far is pretty much a chain of throwing parts at the problem rather than proper diagnostics… Sometimes the former is a better way of going at the problem if you know that there are only a few possible causes, and swapping parts is cheaper/faster than doing the full diagnostics… or if those parts are due for replacement anyway… otherwise a good repair manual, in particular a good factory manual, will step you through an entire diagnostic tree to narrow down and determine the problem…

Have you sprayed a combustible liquid (like carb cleaner) directly into the intake, and does it run then? (or course after you turn the key).

I would be surprised (very) if the vapor separator was the cause of this problem.

Exactly what I am saying. a vapor seperator does not cause a crank no start.

Did you try Andrewj’s suggestion of asking at the Subaru site? Those guys know their Soobs.

Thanks for the link to ultimatesubaru; I got an answer to my question from someone on that forum. I’m curious as to why “tester” didn’t get any criticism for posting a smart aleck response to my reasonable, respectful request for information, and yet my frustration with said smart aleck response got me a lot of criticism for my attitude. Maybe you’ve never been without transportation, out in the country where there’s no public transport of any kind, and if you’re lucky you never will be. Hope you never have to walk, hitchhike and beg rides from friends and neighbors for multiple weeks while trying to get the correct parts and the correct info. for car repairs. If you ever do, I’ll be happy to commiserate with you, but I might still be walking/hitching the 5 miles to the library to use a computer.

Because Tester didn’t give you a smart alack response. He gave you the general area but wasn’t sure whether it was directly above the tank or not. If he knew the exact position, he would have told you. Tester is a professional tech and one of the most knowledgeable techs on the site. Even with us professional techs here, none of us know everything about every vehicle made. We are here, giving people like you FREE advice on our own time to help YOU. You came off like a hothead from the get go. You were frustrated in trying to get a 22 year old vehicle to start and you made it known, rudely and that’s why your post went unanswered right away. Dont bite the hand that feeds you. We went on to help people who actually appreciate the help.


I agree with you OK4450. I suspect he may have a fuel filter or fuel pump problem.