LOYALE Engine Codes 24 and 34: Air Control, EGR

[Ocarand]

Hi there,

 

I've read a few threads already but I want to get some things straight because I'm not a mechanic.

 

I have a 92' Loyale Wagon, SPFI, 5spd manual, 130k Original Km's (80k miles). 

 

Codes show 24 and 34. (http://www.troublecodes.net/subaru/)

 

24 Air control valve or circuit 34 EGR solenoid or circuit

 

The car starts every time, Idles a bit high on cold start (but only owned it since the beginning of winter so not sure how it idles normal in warmer temps), seems like it struggles at about 110+ km/h (70mph) but I understand it's not a fast car. No funny sounds coming from engine.

 

Based on my web knowledge about vacuum leaks it doesn't seem to be a vacuum leak. So it must be these valves/solenoid?

 

Reading a bit more stuff I found out the Air control Valve and EGR Valve can build up carbon deposits.

 

My question is:

 

If I replace just the Air Control Valve and the EGR solenoid will that clear the codes? 

 

For the Air Control Valve code - Will carbon build up in the throttle body or in ACV trigger the check engine code?

For the EGR code - Will a dysfunctional/clogged EGR valve trigger the CEL or is it just the solenoid?

 

I understand if I replace the valves and give it a little TLC, its probably good for the long run.

But want to get your guys input and solutions for more confidence and less frustration when the doing job

A lot of the threads tend to go into more technical stuff or are just very basic and old so I decided to start a new thread.

 

 

Thanks for reading

 

Randolph. 

 

 

[DaveT]

99% of the egr code is the solenoid coil is failed open. There is a link to my solenoid swap page somewhere on another code 34 thread.

 

I have never experienced drivability issues caused by code 34. It only indicates the coil of the solenoid, nothing more.

 

The idle air control valve effects idle. Once the throttle is open, it has little effect.

[Ocarand]

Okay thanks, I found your solenoid swap page!

[Craigar]

I was getting code 34 on 94 Loyale SPFI 3AT also. Long story short - I ran "electronic cleaner" through EGR solenoid  (suckin & blowin on the hose a bit..), cause it sounded wimpy jumping it straight off the battery, then 10 minutes later came back and it got stronger sounding. Put all the hoses back on cleaned the connector put it back together and at first still had CEL, than 10 minutes went off then 10 more back on, parked the car came back in a half hour, started it & CEL went off immediately & staying that way ( 3 more little 10 minute trips w 15 minute stops...) NOW I'M gonna pray it's working tomorrow so I can CA smog it.

 

Thank You Gloyale for the info about disconnecting both wires by the firewall - seems so "illogical" that the one with the white connector is a locking connector (and the green isn't) - and my Haynes manual had me taking apart a lot of unnecessary similar connecters next to the fuse box, under the left side of the steering column - and my "white connector" by the firewall was hooked up, which kept the CEL on all the time, (once I put a bulb in- cause someone had REMOVED it!)

 

 

I also made the hose from the solenoid to the valve tighter on the valve end by cutting a piece of insulation from a cable of similar size and slipped it over the the connecter tube then crammed the hose on to it - and the hose had no cracks,, just "bell mouthed" so I wasn't sure of a tight seal

 

 

but here's somthing that seems strange to me, the O2 light in the ECU is still flashing all the time from what I can tell (8 shorts = code 08 = Model designation, CA automatic SPFI) and I have both the green and white connectors(shown above) disconnected?

 

 

Edited March 29, 2017 by Craigar

[DaveT]

The o2 light blinks a normal code. The green and white 1 pin connectors put the ecu into diagnostic mode or clear codes or read memory mode.

 

In 49 state cars, the 34 egr code is set by only one thing. The ecu can tell if the coil is open electrically. The ecu does not know if the solenoid valve itself opens, or the egr valve. In ca cars, there is a sensor for egr gas temperature - that one should sense a problem such as the solenoid doesn't allow the egr to open when it is supposed to. It should give a different code, but I am not certain, as I have not had that situation arise.

[DaveT]

It is normal for the 34 code to come and go when the solenoid coil is open.

 

I use Toyota solenoids to replace the Subaru ones. They are many times more reliable.

[robm]

There is a generic EGR solenoid out of India on Ebay that works.  US$21 with shipping. It connects right to the stock connector on the wiring harness.  It works fine.

[Craigar]

Well, tomorrow came and the CEL was off - for ONLY about 5 minutes - and on the way to the smog check station it came back on (and so did my electric radiator fan, first warm day we've had in a while, about 75 degrees) and stayed on until this evening when I started it after 2hrs parked, it was on BUT after I went into reverse it turned OFF (and my electric radiator fan stayed off cause it was only about 60 degrees outside) . Got home, CEL was back on (& O2 light still shows only 34 code=EGR solenoid)  put in reverse gear and it went off... weird ,, Thank You "Subaru Nut"  gonna go and track down the EGR solenoid out of India on Ebay, see that solves it - but I bet it's actually a WEAK OR BAD GROUND connection somewhere (over the rainbow..)??

 

Subaru Nut, is this the ebay one your suggesting? The female connector is aimed in the oposite direction, which may not matter cause I would still have to make some wiring to compensate for the non-existant "pig tail" wire that's on the original Hitachi solenoid?

http://www.ebay.com/itm/UNIVERSAL-VACUUM-SWITCH-VALVE-EGR-SOLENOID-VALVE-/302173573832?hash=item465af2d2c8:g:Kj8AAOSwT5tWJJrB&vxp=mtr

 

or is a different universal vacuum solenoid?

 

Thank you

Edited March 30, 2017 by Craigar

[DaveT]

That on and off is typical of the coil open failure of the egr solenoid.

 

Robm is the member who knows about the one from India.

 

I have a web page for the Toyota solenoid mod.

 

It doesn't hurt to check grounds, you want those in good condition also. Clean them and apply anti seize compound.

[robm]

Yes, that is the one.

 

The electrical connector fits perfectly.  No problem there.

 

The mount is a bit different. It will bolt on, but you will need some new vacuum hose because the old ones are too short to connect to the valve.

 

If you can find one from an old Toyota at the wrecking yard, you are better off, as you won't have to wait to have it mailed to you.  I had to get new, as there are no cars of that era left in the autowreckers around here.

 

Oh, and Robm is my handle, "Subaru Nut" is my description.

[Craigar]

Man is it hard to see the trees through the forest.. Now I see members handle on the grey bars between the post - and also *duh* see there are many professed "subaru nutz" , or do we get elevated to these (and further..) heights on the USMB levels of rank? (maybe I should re-read the newbie info, and maybe more of it ) AHH YES - you nuts have MANY Posts!!

 

back to the solenoid, an old saying is "heat is the bane of electronic components" and generally resistance increases with heat,, Sooo I've unscrewed mine and (temporarily, only for a year or two..) suspended it with a hanger made out of a paper clip (cause the intake manifold gets pretty hot pretty fast), now I'm gonna try to make a run to the smog shop... I'll be back

 

(also I'm having trouble accepting/believing the it could be intermittently open - unless the heat is "spreading the gap" in the break in the coil.. ,, and seems contradictory that every time I hit it with jumpers (admittedly when it's cold) from the battery, it clicks -- probably would be a respectable test if I did it when it is hot also)

Edited March 30, 2017 by Craigar

[DaveT]

I've never had one intermittently open. It's just seemingly random when the ecu decides to check it, and then take the action to report it.

 

The solenoid is only activated under certain circumstances.

[Craigar]

well after 2 minutes today the CEL came BACK ON- Sooo I decided to try jumping it again straight from the battery and it DIDN'T click - I think it's "stuck" - but sure may be an open coil, and I didn't have an ohm meter handy - so I'm going to check it tomorrow... Well I could get the "universal" one from India on fleabay, but it will take 2 weeks to a month to arrive - and my CA tags expired in February, and now we got to pay something like $50 for a "processing fee" here even on a "fix it "ticket... and tommorows "April Fools day" and I am qualified A+ for being proverbially late SO I went to auto zone & they suggested "Peerless Auto" and they will have the original Hatachi tommorow for the same price as on on fleabay $49+tax, and then I don't have to worry about the smog guy looking at it funny either...

 

I'm going to suspend it (after I pass smog) to keep the heat from the manifold from roast    ing it (i surmise) to an early death - also this car came from Arizona and they are famous for roasting weather in general. I tried "suspending" it today (with a untwisted paper clip), but it didn't help..

 

and then tonight for about 20 minutes the CEL was off (almost as unreliable as me)

Edited March 31, 2017 by Craigar

[DaveT]

The CEL on and off is completely normal for the open coil failure. Almost every oem solenoid I have had has failed. I've been running ea82 cars since 1988. My same Toyota solenoids get moved from car to car, since about 1990. I'm in CT it is nowhere near as hot all the time here.

[Craigar]

So i picked up the new one, plugged it in and my CEL STILL CAME ON!  and I felt fear that I had a bad power transistor in my ECU,,, then I hooked together both the test & clear codes wires and all 3 of the things clicked (a relay, another solenoid, and THE NEW SOLENOID) and THEY ALL MADE NOISE, so I felt there was still a chance..

 

unhooked the connectors, turn of the key turned on & started and the CEL TURNED OFF = Hooray! Do a few trips and it stayed off for the entire time.

 

Got home and checked ohms of my old solenoid and it read 39.5 ohms, so I looked closely at it and saw there is a metal "cage" around it that has 90 degree folded tabs (that go through a bracket pulling (that's in a groove on the plastic end, with the mini air filter & pipe that goes to EGR valve)) that look like they could be bent straight & take it apart to see if I could see any thing obviously wrong, when I did the metal pipe section easily pulls out AND IT WAS DIRTY INSIDE the cylinder/chamber,

I cleaned it out with a dry Q-tip and wiped down the plunger/piston. Probably got dirty and gunked up from the car backfiring at lower rpms, mostly cause of seriously old spark plugs (bet they were the originals - the gap had spread/erroded to .065 or more). Hooked it up to the electrical connector in car and it works - even shot a vid of the piston moving (before I put it back together) when hooked up in "test" mode, but I got to go to bed for now.

 

Here's images that  help show the details

Edited April 1, 2017 by Craigar

[rapidfire10ring]

It is normal for the 34 code to come and go when the solenoid coil is open.

 

I use Toyota solenoids to replace the Subaru ones. They are many times more reliable.

"Someone" at some time posted a how-to on doing this with photos of the Toyota Purge SolinoidSensors replacing the Subie ones and the wire snipping and heat-shrink repairs.  I recall it was in some folksy Mother Earth type on-line forum.  Can't find it anymore.

[carfreak85]

On ‎3‎/‎31‎/‎2017 at 5:06 AM, DaveT said:

The CEL on and off is completely normal for the open coil failure. Almost every oem solenoid I have had has failed. I've been running ea82 cars since 1988. My same Toyota solenoids get moved from car to car, since about 1990. I'm in CT it is nowhere near as hot all the time here.

@DaveT Do you know the part number for the Toyota part?  I've got a code 34 on my EA82T.

[DaveT]

I never had a part number.......   They were common on Toyota cars from the same general model years.  I got a handful of Toyota and Honda ones at a local scrap yard for 10 or 20 $.    I have a web page write up of how to use them - I just have to find a new hosting service, as the one I had it on went away.

I'd go to a local yard, where they let you pic & pull.  Look under the hood of a few of the older non super fancy models.  Look for similar sized vacuum lines.  The solenoids I found are narrower and longer than the Subaru ones.  You have to replace the connectors with the ones from the dead OEM one.  Do a little testing to verify which port routs to which, powered and not.  [the specific info for the ones I found is in my web page] .   I'll see what I can do about getting my pages back online.