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lack of power. help a brotha out.


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so, i have a 91 loyale. ea82 nonturbo.

 

when its cold its got a hell of a hesitation, especially when cold before 3k. not to mention its just wicked slow when cold.

 

cap-rotor-plugs-wires are less than 2 weeks old. they made a great improvement on the power, but there is still next to no power below 3k and not impressive above.

 

i had the car dyno'd at school with only fresh plugs gapped to .045, a seafoaming in the intake, crank case, fuel and a fresh oil change.

 

ive replaced quite a few vacuum hoses, but not all. i tried spraying starting fluid around the engine bay, but no results.

 

idle is a steady 1k rpm, and does not hunt. idle only dips lower in random condition (ecu still sees warm temp but coolant and oil have cooled).

 

it has lifter tick when really cold for no more than 5 sec, but noise is completly quiet afterwards.

 

help me out and point me in the right direction.

 

 

edit: forgot to post dyno result. in 2nd gear, 77whp , ~230wtq

 

timing is at 20*

Edited by maozebong
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You realize that when brand new the car only had 90 HP right? What tires do you have on it?

 

EA's are scary slow - especially when you add some larger tires, etc.

 

Have you verified both the ignition timing and the valve timing? Perhaps one t-belt is off a tooth or something.

 

Ignition timing should be set to 20 degree's BTDC. Use a timing light.

 

GD

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valve timing is more than likely not off if i had to guess. whole timing assy is less than 20k miles old.

 

ignition timing is at 20* with green connectors connected to lock timing.

 

dyno was 77whp and ~230wtq in 2nd gear. is this about right for a healthy ea82 spfi?

 

tires are stock sized 185/75-13

 

oil is conventional 10w30. never hi milage or synthetic. tick only happens at startup on the coldest ohio mornings (~0*) and never lasts longer than 4 seconds.

 

egr valve works, the valve solenoid not positive. when i pull up on the diaphragm of the valve it starts to stall.

 

i only have one check engine light, and its 35 (evap solenoid?) thats it.

would the purge solenoid be enough to interfere with acceleration below 3k?

 

also, idle is 1000rpm, and holds solid.

 

only things i have not checked is fuel pressure and fuel filter. and a few random vacuum lines related with the pushbutton 4wd. it just seems like below 3000rpm it feels like its holding back. also more throttle works to a point, then, just intake noise. seems to like feathering into the throttle more than WOT.

Edited by maozebong
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Check the engine temp sensor on the thermostat. Do you have compression readings? You sould like you are educated in auto service, like you are taking auto classes.

 

But there is a point with old subarus you have to throw standard auto knowledge out the window and glean from Subaru Experience.:grin:

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miles,

 

this is why im asking my fellow old gen subaru nuts on some advice on this. you guys have said "soob mojo" and it'd be a huge help to not diagnose all day in the snow.

 

i have taken automotive classes, and graduated with an associates degree in applied automotive sciences, ASE's in steering/suspension and brakes (would have more if i cared enough to get them:lol:

 

i also have a certificate from the same school for hi-performance (consists of a advanced class for: block and rotating assy, cyl heads and porting, assembly, fuels and tuning, and trans/driveline) its safe to say im not a noob for being only 21. ive built 5 performance motors so far and a handful of rebuilds.

 

ill test my temp sensor tomorrow, check fuel pressure (spec is roughly 20 psi right?), compression, and get back to you guys. thanks for the help.

Edited by maozebong
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dyno was 77whp and ~230wtq in 2nd gear. is this about right for a healthy ea82 spfi?

 

That's completely normal and doing fine. The engine makes 90 HP at the crank - all things considered it's doing pretty well to put 77 to the ground.

 

i only have one check engine light, and its 35 (evap solenoid?) thats it.

would the purge solenoid be enough to interfere with acceleration below 3k?

 

Nope - replace the solenoid with a 33 Ohm, 5 watt resistor. It's just an annoyance CEL though. Does not affect power.

 

GD

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thanks GD

 

i guess my fears are unfounded. too bad FHI was using too much intake manifold theory and not enough testing when they made the SPFI heads and intake.

 

old intake theory said that 2-phase intake tract said (2 phase meaning one long log runner that connects a section to feed each cyl. 1st phase is the log and 2nd phase is each cyl runner) that the 2nd phase should be as short as possible while keeping the ideal air flow velocity through the runner. but as we have found out, intake tract design does much better with a proper length runner and a plenum than the old log style.

 

fuji enginners really took that to heart with the ea82.

 

edit:

dug up my dyno sheet,

 

77.1whp @ 5k

282.8wtq at 3k

 

now another thing i was wondering, is there any poor man's HP tricks for these motors? i noticed the muffler was fairly restrictive with the inlet/outlet differences, so that's first on my list, maybe a custom made header if my boss gets off his rump roast and orders me a tubing bender.

Edited by maozebong
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Yep - the log manifold is a terrible design. So is the head porting. As someonee recently put it - the EA engine's have the bottom-end geometry of an F1 race engine and the manifold/head setup of a tractor. :-p

 

Being large bore/short stroke - they do like to rev and you have to if you want any power from them - shift at 5k. You will never hurt it at all doing that on every single shift.

 

GD

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Yep - the log manifold is a terrible design. So is the head porting. As someonee recently put it - the EA engine's have the bottom-end geometry of an F1 race engine and the manifold/head setup of a tractor. :-p

 

haha :lol: funniest thing i have heard all day!

 

i bet RAM casts their own heads for these, and i can guarantee nothing is even close to the same! it would be awesome to have a guy like larry widmer of endyn to a custom cast ea head.

 

if it was ITB'd or twin manifolds, with a properly designed cylinder head the EA could be revved to the moon and stay up there (with a supporting valvetrain of course) and make great motor for racing.

 

i love hindsight engineering discussions:popcorn:

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I'm sure you had a vacuum gage on it as you've suspected a vac problem from the beginning. The exhaust becomes more restricted as internal pieces break loose and clog the output. hondas were good for that. The muffler cases were well made but much humidity resided inside from short trips and parts/plates would float to clog the exhaust.

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it would be awesome to have a guy like larry widmer of endyn to a custom cast ea head.

 

It would be interesting, no doubt about it!

 

Were you ever on the old ENDYN forums? I posted some pics EA heads back in the day on there and we all got some laughs out of it. In all fairness, the chamber/quench isn't that bad (pistons perfectly match the quench area of the head providing lots of mechanical octane).

 

Larry has done some work with siamesed MG heads. I'd bet he'd have a few tricks for EA heads (particularly MPFI on the exhaust side).

 

Working the short turn radius of the intake and exhaust is worth doing. I've done it on a SPFI Loyale and MPFI GL-10 and it netted mileage and power. The seat intersects the short turn in the form of a sharp edge. The idea of a short turn radius was foreign to these engines. You can make it better, but you'll still get flow separation there. My loyale went from pathetic, to not so bad on the highway. Mileage skyrocketed.

 

Here are some comments/pictures of some of the work I did on the MPFI heads. I don't have the photos of the intake or how I finished out the chambers/seats ... but basically radiused the top seat cut into the chamber and de-shrouded a bit where the valve seat meets the chamber wall.

 

http://www.themacaddress.com/?p=99708161

 

SPFI:

LOL! -> http://web.me.com/dgiessel/Pictures/mac_address/automotive/ea82_rebuild/1_6_05/P1060016.JPG

Little better -> http://web.me.com/dgiessel/Pictures/mac_address/automotive/ea82_rebuild/1_6_05/P1060015.JPG

 

http://web.me.com/dgiessel/Pictures/mac_address/automotive/ea82_rebuild/1_6_05/index.html

Edited by Tycho
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  • 4 weeks later...

I have a similar lack-of-power (henceforth LOP) problem with my old 1986 GL Loyale 1.8L nonturbo FWD. I was dumb enough to try and get a response here on an old - very old (5 years) - thread, to which no one replied. I hope I'll have better luck here. What caught my eye with the old thread (http://www.ultimatesubaru.org/forum/showthread.php?t=38576&page=4) was something that a user by the name of Midwst said: that the LOP could be caused by an overheating that did permanent damage (to what, exactly, the guy didn't say, but maybe he meant the head gasket).

 

Here was my pitch back then (about 8 months ago):

 

---*

 

Hey! The bit about "overheated and has engine damage" really struck a note. My old 86 Subaru GL Loyale used to have lots more uphill pull until I had an overheating problem (one of the pipes that came out of the engine developed a hole because the former owner ran it with water only (!)), and it heated up to the border with the red area. Ever since then, my Loyale has been a gutless wonder, it idles like crap, but runs slightly better when it warms up, but the main problem is the lack of power which only begin to manifest itself AFTER the overheating problem. A damaged head gasket? A damaged (melted?) timing belt? Thanks for 'listening", and I would appreciate any informative reply, especially replies that suggest some process of elimination for arriving at the problem.

 

---*

 

Well, to update this a bit, I was recently trying to get onto the freeway with a slightly cold motor (given my car's gutless state, it has to be really, really warmed up before it will accelerate even reasonably, and it wasn't this time) and the ramp ahead was running out fast, a car was coming up behind me fast, so I floored the damned thing, and to my surprise, it took off like it had a rocket behind it (remember the scene in Toy Story? :cool:), which makes me think that there must be a dead spot, meaning something gummed up inside the carburetor.

 

The thing is, though, the noticeable gutless state only started after I had that very serious overheating (the needle almost reached the north pole position!). However, I hadn't had the car all that long, so maybe I had simply been driving it timidly. I dunno, but in any case, if it can respond as aggressively as it did when I floored it, I would guess that it can't be a head gasket problem.

 

Anyone got any suggestions (and please don't speak in mechanic-speak, cause I'm not much of a mechanic, though, years ago, I took an all-around brake & tune-up course and aced the test :banana:, but maybe they got my test score mixed up with someone else's).:burnout:

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Sounds to me more like a lazy vacuum secondary carby issue,providing your model is a carburettor version not SPFI.

After all our model lineup in Australia does not line up exactly with the US but some are virtually identical with just differing model codes.

 

It is amazing just how often anything to do with a carburettor opening to give more power and vacuum operation to achieve it falls over when not very old.

We see it all the time at work ,with Mikuni and Keihin Bike carbies when the slides are lazy to open or will not fully open.

Hitachi car carbs have the same issues with the secondary butterfly being reluctant to play ball at times,do a search for the weberising mod to the linkages or just overhaul and fit a junkyard weber for major improvement in power and response.

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Pursuant to the advice on installing a Weber carburetor...

 

How can I determine what engine type I have, is it part of the VIN, or is it stamped on the engine block somewhere? Most users in the above seem to suggest that my engine type will be an EA 81 or an EA 82 (but which is it, and if not, what else could it be?). To buy the Weber carburetor, I will apparently need to know my car's engine type - most parts companies don't seem to lead you through the selection process, holding your hand, like they do at, for example, Autozone (and Autozone doesn't have Weber carbs for my car).

 

Thanks.

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I think I may be getting somewhere on this problem...

 

To channel your thinking in the following, I believe that the problem may boil down to an improper adjustment of the accelerator/ choke cable. Here's the skinny:

 

When I experienced the overheated engine/ coolant leak problem, the mech had to remove a lot of the "junk" on top of the engine in order to get to the water pipe with the hole in it that was the source of the leak. Including, disassembling the accelerator/ choke cable. When he was done, he reattached everything, but the car ran poorly - it idled like dung (the human version :eek:)!

 

Unfortunately, the mech's wife had fallen and broken a hip and he got a bit pressed for time, so I ended up trying to adjust the idle myself, which I thought involved adjusting the accelerator/ choke cable, because I could see that the mech had not reattached it in the original position (I could easily "read" this from the swath of clean threads that should have been dirty).

 

So I went about trying to adjust it myself, but still it did not run well. In Reno (I was living in the SF Bay area before, where I now live again), I had another mech - he had even worked as a garage mech on Japanese cars, including soobies - adjust the idle, and he went to the same gizmo (the accelerator/ choke cable) to adjust it as I had gone to, but the car simply did not idle well. I did a lot of slight monkeying with it in the months after that, but it still idles - and accelerates - like crap.

 

Finally (recently) I bought a Haynes manual, and from that I see that the idle adjustment is in a completely different place (!) - is a completely different adjustment - than the accelerator/ choke cable!!

 

These experiences have more or less convinced me that my problem, the LOP (Lack of Power) problem, is that the adjustment on the accelerator/ choke cable is such that the combustion chamber receives a gasoline-air mixture from the carburetor that is either too rich or too poor in the medium range, but when I floor it, everything (all the cocks) open up to the maximum, and the gasoline-air mixture is perfect, which is why it only runs/ accelerates properly when I floor it.

 

So, there is quite likely no causality at all between the overheating and the poor performance, other than the fact that the accelerator/ choke cable was not reassembled to its proper position after the cooling system leak was repaired.

 

If we assume, for the sake of the argument, that this is the problem, the how in the heck does one adjust the offending cable "properly"? I have tried to bone up on this in my Haynes manual, but have found nothing specifically on this topic.

 

Any suggestions (I am loath to go to another mech when the last one I hired tried to set the idle by adusting the very same accelerator/ choke cable as I, greenhorn, had!)?

 

Thanks

m

u

c

h

o

!

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I think I may be getting somewhere on this problem...

 

 

... so I ended up trying to adjust the idle myself, which I thought involved adjusting the accelerator/ choke cable, because I could see that the mech had not reattached it in the original position (I could easily "read" this from the swath of clean threads that should have been dirty).

 

So I went about trying to adjust it myself, but still it did not run well. In Reno (I was living in the SF Bay area before, where I now live again), I had another mech - he had even worked as a garage mech on Japanese cars, including soobies - adjust the idle, and he went to the same gizmo (the accelerator/ choke cable) to adjust it as I had gone to, but the car simply did not idle well. I did a lot of slight monkeying with it in the months after that, but it still idles - and accelerates - like crap.

 

Finally (recently) I bought a Haynes manual, and from that I see that the idle adjustment is in a completely different place (!) - is a completely different adjustment - than the accelerator/ choke cable!!

 

 

Thanks

m

u

c

h

o

!

 

:Flame:

 

Hmmm, I tried adjusting the idle screw, but it didn't make the slightest difference where I positioned it (it rotates about ½ circle). I fiddled again with the throttle cable (yeps, that's what it's called, I have since learned) and got it to idle pretty good, but I have no idea how the LOP situation will be. I have in the meantime ascertained that the spring on the accelerator (gas pedal) is shot (the pedal sticks, but I can always pull it up with my foot, though it sometimes revs pretty wildly!!!). To my amazement, no part dealer lists this item (not even a complete accelerator assembly), not, even, Subaru USA! Next stop: Pick-n-Pull! :horse:

 

In the meantime, I'll see if I can rig some kind of spring reinforced string from the gas pedal up to the steering column or wherever I can attach it so that the pedal pops back when my foot isn't resting on it (I'll have to hope I don't get pulled over in the meantime! :dead:).

 

ps: If anybody responds to my altered thread, please copy the "AND, a noob too, please!" part and paste it into the Title, that way I'll know that you are directing your reply to me and not to the other guy. Thanks!

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  • 2 weeks later...

Mysteriously, the gas pedal now pops back, so something must have pinched it, or maybe it was the cold weather (an argument for some WD40!). Anyway, apropos the carburetor - which I am now convinced is shot, since the idle screw now turns about 50 revolutions before it bottoms out, whereas before it only turned a half-circle, and the sleeve housing was firm before, whereas now it is floppy, PLUS, no matter how I adjust the idle (now with a warmed up engine), it makes no difference, PLUS, PLUS, suddenly the idle jumps from 800-900 RMP to 3000 RPM and there is nothing that can cause it to settle down again, except when the engine decides that it has had enough of that nonsense and settles down again to 800-900 RPM!!! - where can I find the OEM number, or whatever, that belongs to this carburetor?

 

I figured that it would be possible to just click my way through the options at the online car parts company and it would then tell me which carburetor (make that refurbished carburetor!) I needed for my car, much like when I search for a new air filter, etc., but no, it offers me a whole pile of options! Any qualified help will be appreciated! Hope you all had a wonderful President's Day! zzz

 

 

Subaruru

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