idosubaru Posted December 27, 2020 Share Posted December 27, 2020 If you have measurable symptoms You can swap injectors as an easy test and see if the symptoms move with the injector. If you swap injectors 2 and 4 and the issues go from #4 to #2 then you know the injector is the culprit. Of course this only works if you have predictable symptoms or something measurable. Like pulling the injector plug trick you used early on. Quote Link to comment Share on other sites More sharing options...
davepak Posted January 13, 2021 Author Share Posted January 13, 2021 ** Sad update ** After trying the result wasn't good. The car started for some time but then Harness on Injector #4 SMOKED. Injector #4 is now leaking the pressure of the fuel pump. The car died. I tried again and then I heard an awful clank from the engine. I tried a few times and now it won't start, actually, it won't turn. Maybe a valve? Maybe I'm actually not sure. I might be declaring this project a totally fried XT. Quote Link to comment Share on other sites More sharing options...
davepak Posted January 13, 2021 Author Share Posted January 13, 2021 (edited) **Happier update! ** Well, it looks like the FrankenSubaru is alive. These are the latest updates : -I got the new ECU a remanufactured unit by Standard of Canada. -Following advise, I changed the oil and also flushed the cooling system and replaced it with ready mix Coolant. -I completed a brand new wiring installation for the radiator fans. This included fixing the auxiliary fan (for the AC circuit) and the wiring for a main fan with a separate relay, yet both share the same signal from the thermo switch, making them start simultaneously but fed from different sources. They work spot on, by the way, the thermo switch is for a Hyundai that opens at lower temperature than the standard Subaru switch boiling hot head gasket killers! -I found injector #4 leaking again. It was working but there was a leak around its base. FGS! So I got another injector from the junkyard. This one worked fine. -I found green corrosion on the connector of the throttle position switch. I cleaned it both connector and leads. And did the same for the MAF's connector and leads. With these fixes done the car started right away and to a somewhat smooth operation. So I worked on: -Idle adjustments, this was really a PITA, that included swapping a MAF, throttle cable adjustment, idle screw adjustment, ignition timing, new rotor and distributor cap. -Next is a second "field test", as I went for a spin around the block and noticed that dreaded hesitation and sputtering when going uphill. At this point it SEEMS better and more stable at idle, and when ramming the gas. Early conclusions: I'm yet to really know what was the real problem in the first place. I went through so many systems and so many fixes, that I just wonder if this car is so sensitive, complicated and badly aged, that it developed all these problems. After all tests I'm overdue to take it for the mandatory yearly inspection so it's street legal. That'll be next week most likely. Early thanks to all the great USMB members that helped me out! Special thanks to @idosubaru @DaveT @naru2 @john in KY I'll post more updates soon Edited January 13, 2021 by davepak Content added 4 1 Quote Link to comment Share on other sites More sharing options...
el_freddo Posted January 13, 2021 Share Posted January 13, 2021 I hope things keep looking up for your sweet ride mate! Cheers Bennie Quote Link to comment Share on other sites More sharing options...
davepak Posted January 14, 2021 Author Share Posted January 14, 2021 5 hours ago, el_freddo said: I hope things keep looking up for your sweet ride mate! Cheers Bennie Thanks a lot Bennie! It's a big improvement no doubt. But.. There is hesitation.. Bogging, sputtering mainly under load. I'm suspecting the fuel pump. It has the fuel pump of an old EA82 SPFI I used to have. I wonder if the fuel pump fails to meet the demands of a MPFI..? I'm checking in fact posts on USMB to see if someone has had the same issues.. Quote Link to comment Share on other sites More sharing options...
el_freddo Posted January 14, 2021 Share Posted January 14, 2021 Could just be the age of the fuel pump not being up to the job. If you can, I’d be looking into getting a new pump. Cheers Bennie Quote Link to comment Share on other sites More sharing options...
DaveT Posted January 14, 2021 Share Posted January 14, 2021 T in a fuel pressure gauge. I don't know the MPFI, but I do know the SPFI is very sensitive to fuel pressure. Quote Link to comment Share on other sites More sharing options...
davepak Posted January 14, 2021 Author Share Posted January 14, 2021 5 hours ago, el_freddo said: Could just be the age of the fuel pump not being up to the job. If you can, I’d be looking into getting a new pump. Cheers Bennie Good idea, I actually brought one fuel pump from abroad. I'll replace it next week. Quote Link to comment Share on other sites More sharing options...
davepak Posted January 14, 2021 Author Share Posted January 14, 2021 4 hours ago, DaveT said: T in a fuel pressure gauge. I don't know the MPFI, but I do know the SPFI is very sensitive to fuel pressure. I had an old GL SPFI... that thing ran without any issues. Engine leaked, all battered up, but it ran. In fact, I kept THAT car's fuel pump, and I fitted it on the XT. I wonder if the pump struggles to meet the demands on the XT now. Also I saw mentioned about the fast idle solenoid..could that be a culprit somehow? Quote Link to comment Share on other sites More sharing options...
DaveT Posted January 14, 2021 Share Posted January 14, 2021 I've not worked on a MPFI - just going by general stuff... Fast idle should only be able to make idle faster, not cut / limit fuel at driving speeds & loads. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted January 16, 2021 Share Posted January 16, 2021 In addition to the pump - Maybe the fuel pressure regulator as well. Doesn’t it have a vacuum hose - pull the hose and see if it’s wet inside. I think SPFI and MPFI pumps are interchangeable if not identical. Like 30+ psi. The carbbed engine pumps are much lower fuel pressure. Ive gone through 3-4 EA used pumps trying to get a good one. They don’t seem to be aging well when unused, so if it sat for any period of time...and maybe even if it didn’t, it’s suspect. Quote Link to comment Share on other sites More sharing options...
davepak Posted January 16, 2021 Author Share Posted January 16, 2021 10 hours ago, idosubaru said: In addition to the pump - Maybe the fuel pressure regulator as well. Doesn’t it have a vacuum hose - pull the hose and see if it’s wet inside. I think SPFI and MPFI pumps are interchangeable if not identical. Like 30+ psi. The carbbed engine pumps are much lower fuel pressure. Ive gone through 3-4 EA used pumps trying to get a good one. They don’t seem to be aging well when unused, so if it sat for any period of time...and maybe even if it didn’t, it’s suspect. This is an area I haven't worked much on, but I had bought an aftermarket fuel pump and an adjustable pressure regulator, the plan is to fit both of them and see if this solves this hesitation problem. What I've noticed is that the car is working smooth and at some point when hitting the gas it sputters and it "drowns" so I have to stop the car, keep the gas until it picks up again, as if it had a carbbed engine and there was dirt that needed to be passed through.. @idosubaruyou mentioned to check if the vacuum hose was wet.. Meaning "fuel wet" where the pressure regulator might be faulty? Quote Link to comment Share on other sites More sharing options...
idosubaru Posted January 17, 2021 Share Posted January 17, 2021 (edited) Yes - fuel pressure regulator will cause wet fuel to pass into the vaccuum hose.l....I think. I just asked someone about this like a week or two ago in another thread who mentioned a bad fuel pressure regulator. I always wondered how to diagnose a bad one and they said they pulled the vacuum hose and it was wet inside. I think.... 20 years go I had an XT6 (I’ve owned like 20 XTs), which had a terrible stuttering and drive ability issue I couldn’t track down, no check engine light. I started it and went around bending all the engine harness wires in my hand, massaging them, start to finish. When I got to the TPS wiring, about 4 inches from the sensor I could massage the wire and make the engine vacillate between running great, stalling, or stuttering. Subaru wanted $300 for the entire engine harness. I cut out the TPS and wiring and spliced in a used TPS connector and as much wiring behind it as I could out of a parts car. Car ran fine. If you’re seeing this as a potential wiring issue you could try working those wires as I described. I only saw this one time so that’s anecdotal and not worth guessing it could be your issue. but it might be worth a try for the TPS if it sometimes seem related to throttle position. Edited January 17, 2021 by idosubaru Quote Link to comment Share on other sites More sharing options...
davepak Posted January 20, 2021 Author Share Posted January 20, 2021 On 1/16/2021 at 6:19 PM, idosubaru said: Yes - fuel pressure regulator will cause wet fuel to pass into the vaccuum hose.l....I think. I just asked someone about this like a week or two ago in another thread who mentioned a bad fuel pressure regulator. I always wondered how to diagnose a bad one and they said they pulled the vacuum hose and it was wet inside. I think.... 20 years go I had an XT6 (I’ve owned like 20 XTs), which had a terrible stuttering and drive ability issue I couldn’t track down, no check engine light. I started it and went around bending all the engine harness wires in my hand, massaging them, start to finish. When I got to the TPS wiring, about 4 inches from the sensor I could massage the wire and make the engine vacillate between running great, stalling, or stuttering. Subaru wanted $300 for the entire engine harness. I cut out the TPS and wiring and spliced in a used TPS connector and as much wiring behind it as I could out of a parts car. Car ran fine. If you’re seeing this as a potential wiring issue you could try working those wires as I described. I only saw this one time so that’s anecdotal and not worth guessing it could be your issue. but it might be worth a try for the TPS if it sometimes seem related to throttle position. So this is where I am now with the car. I replaced the fuel pump for an aftermarket one, can't say I see much difference in fact the aftermarket seems to whine more than the stock one. But it works. I checked the fuel pressure regulator and as @idosubaru mentioned, I checked the vacuum hose for fuel wetness, it was dry. I adjusted the igntion timing to the dot! The procedure included removing the vacuum hose from the distributor, removing the wiring connector for the distributor too, engine warm at 800 rpm and setting it at + - 25 degrees BTDC. And I got it dead on. I cleaned and tested the fast idle solenoid too. I inspected vacuum hoses and main air hose for cracks or leaks. None found. The car has got an impressive idle and smoothness. BUT When going uphill it boggs down. It is almost comic, because say my foot is on the gas pedal and the car is just bogging at 600 rpm, neither going forward nor falling back just "stuck" there clearly struggling, as if "something" is missing preventing it from ever going "free." Then, at one point it clears, RPMs pick up and it goes. Im really scratching my head with this! And again, I notice that when I am going uphill, that's when the struggling starts, I have to wait, keep the pedal on and wait until it "clears." Another thing is that this happens under load, when I have the car on idle, parked and I depressed the gas pedal, it runs fine, in other occasions it sputters a bit but generally runs smooth. However, when I actually drive it and I have to go uphill, bam! It won't go smoothly, stalls, boggs and only after a while it clears. Any suggestions based on these symptoms? Thanks! Quote Link to comment Share on other sites More sharing options...
idosubaru Posted January 20, 2021 Share Posted January 20, 2021 1 hour ago, davepak said: So this is where I am now with the car. I replaced the fuel pump for an aftermarket one, can't say I see much difference in fact the aftermarket seems to whine more than the stock one. But it works. I checked the fuel pressure regulator and as @idosubaru mentioned, I checked the vacuum hose for fuel wetness, it was dry. I adjusted the igntion timing to the dot! The procedure included removing the vacuum hose from the distributor, removing the wiring connector for the distributor too, engine warm at 800 rpm and setting it at + - 25 degrees BTDC. And I got it dead on. I cleaned and tested the fast idle solenoid too. I inspected vacuum hoses and main air hose for cracks or leaks. None found. The car has got an impressive idle and smoothness. BUT When going uphill it boggs down. It is almost comic, because say my foot is on the gas pedal and the car is just bogging at 600 rpm, neither going forward nor falling back just "stuck" there clearly struggling, as if "something" is missing preventing it from ever going "free." Then, at one point it clears, RPMs pick up and it goes. Im really scratching my head with this! And again, I notice that when I am going uphill, that's when the struggling starts, I have to wait, keep the pedal on and wait until it "clears." Another thing is that this happens under load, when I have the car on idle, parked and I depressed the gas pedal, it runs fine, in other occasions it sputters a bit but generally runs smooth. However, when I actually drive it and I have to go uphill, bam! It won't go smoothly, stalls, boggs and only after a while it clears. Any suggestions based on these symptoms? Thanks! 1. Does it start up right away every time you turn the key or does it ever struggle? 2. How sure are you that the car is running better now than it was? 3. . What do you think improved it? I'm wondering if maybe something you already did has some connection, offers more insight, or needs more attention. 4. I'd massage all the wires you can find in the engine bay. Start at the sensor (coolant temp sensor, MAF, knock sensor (if you can reach that?!?!), Throttle Position Sensor) and massage the wires slowly as far back as you can. Do it multiple times for each sensor. Do this while the engine is idling. If it revs, bogs down, smooths out, stalls - you'll know you hit a bad spot. This is annoying - I had an XT6 that i think did what you're describing, feather that gas pedal or push it all the way down when it's "stuck" and nothing changes until it randomly wants to - but I can't recall what resolved it - too many Xt's over too long of a time. I detailed earlier how on one XT6 I had to replace the wiring roughly 6 inches behind the throttle sensor. I found this by massaging the wires at sensors in the engine bay - start at the sensor and work your way back as I described above. When I got to the TPS the engine would flutter, stall, smooth out - so i knew to replace that. I unfortunately don't recall what symptoms that XT had, but I do know it didn't have any check engine lights and was barely drivable, I was concerned about getting to work. It may have been the one i fixed with the TPS sensor wiring...or maybe not. Again - too many XT's and too much time...don't recall. Quote Link to comment Share on other sites More sharing options...
davepak Posted January 20, 2021 Author Share Posted January 20, 2021 1 hour ago, idosubaru said: 1. Does it start up right away every time you turn the key or does it ever struggle? 2. How sure are you that the car is running better now than it was? 3. . What do you think improved it? I'm wondering if maybe something you already did has some connection, offers more insight, or needs more attention. 4. I'd massage all the wires you can find in the engine bay. Start at the sensor (coolant temp sensor, MAF, knock sensor (if you can reach that?!?!), Throttle Position Sensor) and massage the wires slowly as far back as you can. Do it multiple times for each sensor. Do this while the engine is idling. If it revs, bogs down, smooths out, stalls - you'll know you hit a bad spot. This is annoying - I had an XT6 that i think did what you're describing, feather that gas pedal or push it all the way down when it's "stuck" and nothing changes until it randomly wants to - but I can't recall what resolved it - too many Xt's over too long of a time. I detailed earlier how on one XT6 I had to replace the wiring roughly 6 inches behind the throttle sensor. I found this by massaging the wires at sensors in the engine bay - start at the sensor and work your way back as I described above. When I got to the TPS the engine would flutter, stall, smooth out - so i knew to replace that. I unfortunately don't recall what symptoms that XT had, but I do know it didn't have any check engine lights and was barely drivable, I was concerned about getting to work. It may have been the one i fixed with the TPS sensor wiring...or maybe not. Again - too many XT's and too much time...don't recall. @idosubaruI have just came back from the garage and: The car starts up right away, steady on 1000 rpm until engine warm-up. And it stays there. I have set up the idle at 1000 rpm as it seems to be "happier" there. I can though set it at 800, 850, 900, 950 it wanted to. I'm sure the car is running better now because: 1. It didn’t run before. 2. It now runs steady, there is no clanking or knocking. 3. It used to stall and die right away. 4. All major sensors have been replaced or tested. I have now tested the throttle position switch following the FSM. Where the contact points must indicate resistance or not based on the movement of the throttle. It passed the test. I have just now placed another brand new pump. And it worked. The only thing with the now 3 fuel pumps I have is that they kind of "whine" all three pumps whine and it is annoying and kind of loud. It's bothersome in the passenger cabin because you can hear that "whiiineee". I have checked the fuel pressure regulator and there is no wetness on the vacuum line. I have massaged the wiring near all sensors and no changes in engine behavior were noticed. I'm guessing after all it is an old super-sensitive (and sensor-laden car) that struggles to reach standard operation due to its own convoluted complicated arrangement. Oh and its the infamous Automatic 3 Speed Gearbox (as if all other issues weren't enough) I wish it was a simple carbureted one. Less wires, just start and go.. **sigh** Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted January 20, 2021 Share Posted January 20, 2021 except for the rpm weirdness, I'd suggest checking trans fluid level (while idling of course)..... maybe a vacuum gauge test? you can find info online of the old-school use and all the stuff it can find Quote Link to comment Share on other sites More sharing options...
idosubaru Posted January 20, 2021 Share Posted January 20, 2021 (edited) 1. Could it be the 3AT and not the engine? All of mine have had 4EATs so I’ve never had those early XTs with a 3AT. 2. What sensors can you unplug as a “test”? O2, knock sensor, CTS - it the car runs with those unplugged id try disconnecting them and see. I wonder if the knock sensor is old and too sensitive or lazy when driving? An acquaintance had a Forester I couldn’t diagnose that would stutter and stall a lot. I swapped the entire intake manifold and wiring harness and it ran perfect. Still annoys me that I never figured out what caused it. You could convert to carb if somehow you couldn’t track this down. Bolt an EA82 carb and manifold up and go. I hate carbs but that’s an easy solution if the problem can’t be determined. Edited January 20, 2021 by idosubaru Quote Link to comment Share on other sites More sharing options...
davepak Posted January 20, 2021 Author Share Posted January 20, 2021 2 hours ago, 1 Lucky Texan said: except for the rpm weirdness, I'd suggest checking trans fluid level (while idling of course)..... maybe a vacuum gauge test? you can find info online of the old-school use and all the stuff it can find @1 Lucky Texan this was a grear suggestion, I had left the transmission unattended sort of speak. But I checked the ATF fluid and its full. Somehow I thought of this as plausible place to check. I checked the differential oil and it shows HALF mark. Although I don’t think the differential oil has much to do with the stalling going uphill. I would think low ATF pressure will have a negative effect. So I continue to scratch my head! Quote Link to comment Share on other sites More sharing options...
john in KY Posted January 20, 2021 Share Posted January 20, 2021 I notice that when I am going uphill, that's when the struggling starts, I have to wait, keep the pedal on and wait until it "clears." Another thing is that this happens under load, when I have the car on idle, parked and I depressed the gas pedal, it runs fine, in other occasions it sputters a bit but generally runs smooth. However, when I actually drive it and I have to go uphill, bam! It won't go smoothly, stalls, boggs and only after a while it clears. Sounds silly but try BACKING up that hill and notice if anything changes. 1 Quote Link to comment Share on other sites More sharing options...
davepak Posted January 20, 2021 Author Share Posted January 20, 2021 2 hours ago, idosubaru said: 1. Could it be the 3AT and not the engine? All of mine have had 4EATs so I’ve never had those early XTs with a 3AT. 2. What sensors can you unplug as a “test”? O2, knock sensor, CTS - it the car runs with those unplugged id try disconnecting them and see. I wonder if the knock sensor is old and too sensitive or lazy when driving? An acquaintance had a Forester I couldn’t diagnose that would stutter and stall a lot. I swapped the entire intake manifold and wiring harness and it ran perfect. Still annoys me that I never figured out what caused it. You could convert to carb if somehow you couldn’t track this down. Bolt an EA82 carb and manifold up and go. I hate carbs but that’s an easy solution if the problem can’t be determined. Its just so weird! When revved up, the engine goes smooth, then on the next revved up it sputters, and then it just like "dies" while still somehow turning. It doesnt die completely, it just seems to be running on air. Then it picks up. The problem is, when engaged in gear, eventhough it seems to be smooth, it initially drives, then it goes down to like 600 rpm, not moving forward nor backwards, like "suspended" suddenly it picks up and it goes. It does that mostly going uphill (Under load I'd say?) I've replaced the fuel pump for another brand new one. No noticeable changes. I suspect. Well I suspect firstly that it is haunted. Secondly, I suspect issues with the air/fuel mixture somehow. The thing is, all those systems are fine, in the sense that they operate. It seems as if there needs to be such a precise calibration that becomes unattainable. Ive got sort of a deadline. On friday I have to take it to a mandatory yearly inspection (its overdue for 6 months already) I hope it even drives there. There are a lot of hills there and Im worried Id be going to a certain headache thinking itll let me stranded. Ive got no more budget for any other major repairs. The car is almost worthless even if it was running fine. No way Id hire a tow truck to take it there either, basically, if the car cant even get to its inspection..it means is not road-worthy. Ill do a field test later on today. Next call of action would be to be sold for parts. Quote Link to comment Share on other sites More sharing options...
davepak Posted January 20, 2021 Author Share Posted January 20, 2021 1 minute ago, john in KY said: I notice that when I am going uphill, that's when the struggling starts, I have to wait, keep the pedal on and wait until it "clears." Another thing is that this happens under load, when I have the car on idle, parked and I depressed the gas pedal, it runs fine, in other occasions it sputters a bit but generally runs smooth. However, when I actually drive it and I have to go uphill, bam! It won't go smoothly, stalls, boggs and only after a while it clears. Sounds silly but try BACKING up that hill and notice if anything changes. Interesting point. Ill try it later on on the field test. Surely will tell me a lot about the transmission's behavior! Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted January 21, 2021 Share Posted January 21, 2021 IF you can get it to misbehave while stationary, when it is stumbling, try squirting some starting fluid, brake cleaner or even a stream of propane from unlit hand torch into the intake. If it gets better, there's some kind of fueling problem. If worse....maybe some ignition issue? Quote Link to comment Share on other sites More sharing options...
davepak Posted January 21, 2021 Author Share Posted January 21, 2021 (edited) @1 Lucky Texan @idosubaru I have replaced the fuel pressure regulator with an aftermarket one with a gauge. I set it to (+/-) 65 psi based on the FSM that indicates a "discharge pressure of 61-71 psi" for a MPFI. I noticed some sort of improvement, but marginally. At one point only I stepped on the gas and it launched forward nicely. Then I went for a longer ride and again it stumbled. My foot is down on the pedal, but the car is showing 500 rpm or less. But it doesnt die, it doesnt fall back. Then it picks up again and it goes forward. Like a WAVE. Which is why I suspected the fuel pressure regulator failing to maintain the fuel demands, or even the fuel pump unable to meet the requirements. Both are new now. And the problem remains. I have canceled the appointment for the yearly inspection as I dont think it will drive steadily. Ill try @1 Lucky Texan method of squirting some starting fluid through the air duct tomorrow I tend to think now about the MAF, whether it is faulty somehow. But the thing is, at idle it remains totally steady, no surging, no waves of up and down idling, it doesnt die.I have to MAFs no changes when interchanging them. Transmission wise..ATF is fine and I hear the gearbox working, changing gears, kicking down, downshifting.. (Just in case, reaching out for a mechanic is just out of the question) No money for that and even worse, no qualified mechanic that knows about this particular type of EA82. Again, I wish it was an SPFI or carbureted. I had both types before. It was a start up and drive-away affair. This one is a "start-up (if it does) and see what's wrong now" Edited January 21, 2021 by davepak content added Quote Link to comment Share on other sites More sharing options...
el_freddo Posted January 21, 2021 Share Posted January 21, 2021 I once did an MPFI conversion on my L series before I found forums and saw the light in the EJ conversion world. Mine would surge sometimes when accelerating, other times it would pull like an EA82 freight train. Didn’t matter about the load or throttle position, sometimes it happened, sometimes it didn’t. I recall that if I took my foot off the throttle and back on when this was happening it would clear up. I never found out what the issue was but I suspect it had something to do with the smaller carb fuel return line that my conversion inherited (this was swapped out when I did the EJ conversion). It could be worth removing the fuel cap and blowing compressed air back to the tank through the fuel return line to remove any restrictions in the system. The other thought is that it’s some solenoid that’s sticking - probably one to do with the fuel tank ventilation system, definitely in the emissions control stuff! Shame you cancelled the inspection, I was hoping it would be there to pass and live on, even if it limped over hills for now... Cheers Bennie Quote Link to comment Share on other sites More sharing options...
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