EGR What is it? How hard to replace.

[Sean486]

My check engine light came on one day last week. I pulled over and shut the car off. I popped the hood to check the oil and found that the dipstick was out a little. I pushed it back in after checking the oil, and when I started it again the check engine light was gone. I have driven it a few more times since then and have not gotten the check engine light again.

Today I changed the O-Ring on the dipstick and checked the codes. I am reading a code 34 EGR Solenoid Valve and it continues to read that after disconnecting and reconnecting the negative terminal on the battery. Not sure if that is the right way to clear the code or not.

So anyway, assuming the EGR Valve is bad, is this a minor repair or is it difficult expensive one? Or is it possible that the O-ring on the dipstick being worn triggered the code when it vibrated out? Also ,if it were really an issue with the EGR, would the check engine light still be on?

Thanks

[apocalixto]

My car threw code #56 today. EGR System....and it has been shutting off when i am pulling to stop lights...it runs perfect other than that...
help?

[longassname]

the solenoid is easier to replace than the valve. The solenoid is the electrical vacuum valve part under the intake manifold that puts the egr valve under the computer control instead of just vacuum. The intake manifold isn't very hard to remove if you do it right. Just don't try to take the upper intake off seperate from the injector stacks. Unbolt the injector stacks from the heads and take the whole manifold assembly off as a unit complete with the harnesses, fuel lines, vacuum lines, and all.

Originally Posted by Sean486

My check engine light came on one day last week. I pulled over and shut the car off. I popped the hood to check the oil and found that the dipstick was out a little. I pushed it back in after checking the oil, and when I started it again the check engine light was gone. I have driven it a few more times since then and have not gotten the check engine light again.

Today I changed the O-Ring on the dipstick and checked the codes. I am reading a code 34 EGR Solenoid Valve and it continues to read that after disconnecting and reconnecting the negative terminal on the battery. Not sure if that is the right way to clear the code or not.

So anyway, assuming the EGR Valve is bad, is this a minor repair or is it difficult expensive one? Or is it possible that the O-ring on the dipstick being worn triggered the code when it vibrated out? Also ,if it were really an issue with the EGR, would the check engine light still be on?

Thanks

[longassname]

egr stands for exhaust gas recirculation. It does one thing in order to serve two purposes. It recirculates exhaust gas as the name suggests. It does this to reduce engine temperatures and improve fuel economy. Exhaust gas isn't combustible. The oxygen in it has already been used. So allthough it is relatively hot it's not as hot in the combustion process as fresh air is as it's oxygen burns with fuel so exhaust gas can be recirculated into the intake charge to reduce combustion temperatures; this can allow more ignition advance at light cruise which can improve fuel economy. Also, since exhaust gas is not combustible but takes up space in the cylinders it's like making the engine a smaller engine.

The important thing with egr is to hot have the valve open at the wrong time. If the valve is open at idle it is a relatively large passageway in comparison to the small air passageway provided to clean air through the idle air bypass valve and closed throttle body. Also if the valve is open during acceleration the engine will be ingesting uncombustible exhaust gas as part of the mix when it wants as much fresh air as possible to make as much power as possible.

[Sean486]

Longassname,
A couple questions, if this were going bad would it make the exhaust smell more? Also is the car going to fail emissions if not fixed?
Thanks,
Sean

[SoCal LS-L]

Exhaust odor is attributable to bad catalytic converters (rotten egg smell), or too rich or lean fuel mixture. Since yours is a 92 and OBDI, the emissions test shouldnt be affected unless the valve happens to be stuck wide open, which since you say you only got the solenoid code... wouldnt be happening, and would make the car stall all the time anyways.

[longassname]

ya, for the emissions you'll need to worry about the cats not the egr. I'd fix the cats first then the egr solenoid.

[VectorNut]

I've got a '94 that's giving the EGR System code. How likely am I to pass smog with that? I'm also getting a knock sensor and an O2 sensor code, but I have replacement parts for those.

[benebob]

Sean,
EGR valves aren't that common for going bad on a Subaru UNLESS there is another issue like a bad cat, etc. Usually you can clean them and they will work fine. The first thing I would do is reset your computer by disconnecting your battery for 10 minutes or more. If it comes back then check your vac lines etc going to it. I think you should be able to get enough access to it and if you can squirt it with some carb cleaner if it is gunked up.

It won't fail emissions in your area because of it as you have a "visual check and you have a EGR there. That said you probably would have issues passing if your light was on though at most shops that care.

[Sean486]

Originally Posted by benebob

Sean,
EGR valves aren't that common for going bad on a Subaru UNLESS there is another issue like a bad cat, etc. Usually you can clean them and they will work fine. The first thing I would do is reset your computer by disconnecting your battery for 10 minutes or more. If it comes back then check your vac lines etc going to it. I think you should be able to get enough access to it and if you can squirt it with some carb cleaner if it is gunked up.

It won't fail emissions in your area because of it as you have a "visual check and you have a EGR there. That said you probably would have issues passing if your light was on though at most shops that care.

I've been wondering about this code. The check engine light has not been on for at least 3 weeks, and the car is running fine, great in fact. I am going to try to reset the code again, I only had the battery unplugged for a short time, maybe even less than a minute. Anyhow as long as it continues to run well I am going to ignore it. It's inspection is due in May, and I am going to take it to them early just in case it fails. The garage said the EGR wouldn't fail the car since it was older than a 1995, but who knows, it may need something else, and if it needs work I want a SVX mechanic to do it.

[benebob]

Originally Posted by Sean486

I've been wondering about this code. The check engine light has not been on for at least 3 weeks, and the car is running fine, great in fact. I am going to try to reset the code again, I only had the battery unplugged for a short time, maybe even less than a minute. Anyhow as long as it continues to run well I am going to ignore it. It's inspection is due in May, and I am going to take it to them early just in case it fails. The garage said the EGR wouldn't fail the car since it was older than a 1995, but who knows, it may need something else, and if it needs work I want a SVX mechanic to do it.

Each computer holds some power past when it is unplugged so the 10 minutes was just to get everything to reset back to factory. I had a Xt6 that needed nearly 20 minutes until the seat belt computer would reset. You can always try running some fuel system cleaner through the car if it comes back. Like I said they rarely fail on their own but can throw a code or two every so often if something wasn't right in the fuel or intake system. Dove's has a good reputation up your way and CVM build me the best stock rebuilt SVX tranny on the planet 50k or so ago. Granted they also charge insane amounts and I haven't been there in 5 years or so now.

[Manarius]

If you need somebody to pass your car for you, I know a few guys who will just sticker and go

My car threw the code for the EGR and then the light went off, but the code was stored.

[Sean486]

Originally Posted by Manarius

If you need somebody to pass your car for you, I know a few guys who will just sticker and go

My car threw the code for the EGR and then the light went off, but the code was stored.

Did you actually have a EGR problem or was it just the code?

[VICSVX]

myn has been on forever and the car runs fine and passes emisions...the only thing is the flippin light lol

[Manarius]

Originally Posted by Sean486

Did you actually have a EGR problem or was it just the code?

I'm not entirely sure. I think that it was a code thrown as part of something else wrong with my car. Like Ben said earlier, EGR valves practically never break.