lousey p0400 code. help plz?

[Rudeboy47]

well ive been having this code on my 1999 subaru legacy 2.5L for almost 2 months now.

the things i have done to it.
- cleaned egr
- replaced vacuum lines
-blew threw and cleared all hard lines (intake to BPT and intake to the back of the driver side head)

after doings these procedures the check engine light still comes back on with the same code Ive also noticed this moisture/residue among my vacuum lines ( also in my bpt and the rubber hose from the bpt to the hardline that goes into the intake) not sure where it comes from has any one else experienced this? also noticed the inside of my intake gets really dirty after removing the egr for the second time i had to clean it out again. could this be the problem? is it normal?
really would like to get this solved so i can smog my vehicle. after reading alot about the p0400 among the forums none of the post have been able to help me with my problems alot of them topics end up getting branched off into other problems my car doesn't have. any help recommendations suggestions would be most appreciated :smt023 .

[Dead91silvia]

good luck... I've had it on in my BD for 4 years, on and off... LOL

[Rudeboy47]

good luck... I've had it on in my BD for 4 years, on and off... LOL
:smt022 FML

[pleaidestar]

Egr code isn't it? Bite the bullet and buy a new egr valve and clean the tube, had that code was in my 95 sedan for about two weeks that's all I did. The egr is easy to clean around the valve but its the rod under that needs to be clean so it can move freely. Rod may have a slight score on it or just cruddy enough not to let it do its job. There is also a pressure solenoid under the I/m check that out they are known to go out.

[Rudeboy47]

Egr code isn't it? Bite the bullet and buy a new egr valve and clean the tube, had that code was in my 95 sedan for about two weeks that's all I did. The egr is easy to clean around the valve but its the rod under that needs to be clean so it can move freely. Rod may have a slight score on it or just cruddy enough not to let it do its job. There is also a pressure solenoid under the I/m check that out they are known to go out.
I forgot to mention that the egr is new. And is there a way I can check if the valve works? Under the I/m ? Is that the on on the passenger side that has a line that goes to the TB?

[pleaidestar]

Oh great, new egr...that helps a little..try to figure out why your bpt an vac lines have have moisture in there. The only way to be certain if a solenoid is good or bad is to check it with a multimeter..or trial and error. But that's where I would start, the egr only works at like 25-30 psi, so basically the exhaust gas samples are going in at a medium but steady rate, do you have any pinging or any noises, sluggish behavior when you are driving?

[Rudeboy47]

Oh great, new egr...that helps a little..try to figure out why your bpt an vac lines have have moisture in there. The only way to be certain if a solenoid is good or bad is to check it with a multimeter..or trial and error. But that's where I would start, the egr only works at like 25-30 psi, so basically the exhaust gas samples are going in at a medium but steady rate, do you have any pinging or any noises, sluggish behavior when you are driving?

i do notice the idle fluctuates a bit and in the morning i do hear some kind of rattling noise when the car is cold and stops after the car is warmed up or after i hit over 3k rpm.

[Huffer]

Idle hunting when cold isn't normal - it should go up to about 1000rpm (the scale starts at 750rpm) and stay there until you blip the throttle or the temp rises.
The rattling could either be piston slap (which is normal on a 90s Subaru) or a loose exhaust shield. The exhaust shield will stay rattling, whereas piston slap will go away as the pistons expand and fill the cylinder as they get hotter.

[Dead91silvia]

You can get the small EGR pipe new for pretty cheap at the dealer. I have one, just havent installed it yet.

[pleaidestar]

I'm wondering if the tube is blocked or vacuums are crossed, moisture in there means its not moving. The egr is supposed to help with combustion temps too, not sure if a different code would accompany the 0400 code with like a misfire or o2 trouble code if that were the case.

When I replaced the egr in my sedan a couple years ago it felt like the throttle pos. sensor was unplugged..not responsive and choking out.

[Rudeboy47]

so im still having trouble trying to solve this lousy p0400 code on my car. did a few things such as clean out my egr and change all my vacuum lines and hard metal lines but still does me no justice. i kept fiddling around with it this passed weekend and noticed that my egr isn't opnening i took the bpt off the small metal line under the bpt while the car was runing and it seemed to be blowing air threw that line, i also noticed that there isnt any vacuum going from the bpt to the egr solenoid valve, so could this be my problem? wondering if my bpt is bad and if there's a way to clean and fix or test to know for sure its bad so i can replace it.