EGR Cleaning

Post by **MadeInJapan** » 29 Mar 2009, 17:30

I greased the back of the brake pads today on my rear brakes due to squeaking that was present when I bought the 850 three weeks ago. I also bled the brakes and added new brake fluid so all of my fluids are now new. I don't think the previous owner did any of this at all. The big issue was smoke coming up through the oil dipstick tube despite a PCV replacement a couple of years ago by the previous owner. He didn't know what an EGR was so I suspected it was totally clogged up. Below you'll find pictures and an somewhat of an explanation of what I did and what you will need to do if you're in the same predicament. Unfortunately my dipstick tube still smokes (not as much but still does) so I'll have to tackle the PCV some day soon.

Basically I followed the instructions here: http://volvospeed.com/Repair/egr.php
The hidden 8mm bolt was a bear...I bent a 8mm flare nut wrench to try to get to it but ended up snapping it so I had to use a 1/4 inch slim ratchet and medium size socket. Instructions above say once it's busted loose you can turn the screw by hand but this was not the case for me. It was tight until it was out. That and even if you can get your hands in there, you have to use both hands with one finger from each hand on the bolt's end, so it's a tight fit and a back buster.

In my case, the EGR was totally clogged as was the hole in the intake manifold. This was also difficult to clean because it was blocked solid (no gunk) and so I had to chip away at the build up with an allen wrench and plenty of carb cleaner. Once I got a hole all the way through I was able to insert a cleaning brush. Here is a picture of the brush and you can see the hole that it goes through on the intake:

: cleaning brush.jpg (111.33 KiB) Viewed 33513 times

You need to get that hole totally clear- here's a picture once it's cleaned and clear all the way through (seemed like an hour of brushing and squirting carb cleaner:

: Clean EGR Manifold Hole.jpg (105.06 KiB) Viewed 33488 times

Here is a picture of the actual EGR once it's out of the car. You need to clean all of the holes out really well. If you can pull a vacuum on the vacuum hose connection side (I sucked on mine) the diaphragm will open allowing you to clean between the EGR's top hole and the side which thread onto a brass pipe going to the exhaust. Btw, I had to drill out the build up in the top of the EGR:

: EGR.jpg (25.55 KiB) Viewed 33453 times

Next is a picture of the throttle body all cleaned up and along side it is the temperature sensor that needs to come out of the EGR and also cleaned. I let it sit in a jar w/ carb cleaner and then I brushed it clean:

: Throtle body and EGR Temp Sensor.jpg (101.58 KiB) Viewed 33494 times

Guess that's about it. Luckily I didn't have to take the intake manifold off to do this... Any comments are appreciated and questions are happily answered.
-MIJ

Post by **Ozark Lee** » 29 Mar 2009, 18:22

My son's '96 is the only Volvo we have with EGR and we fixed it when we serviced the PCV. As you found out, the carbon clog in the hole above the valve is like concrete. In my case I had the intake off anyway but I think it took my son a good 30 or 40 minutes of reaming it out with a phillips screwdriver and brake cleaner to get the hole open.

Those stupid bolts that hold the valve on are severe hand crampers. I see you were able to get the flare nut from the exhaust manifold loose enough to remove the valve. I managed to get mine loose enough to clean the valve with carb cleaner while it was still hooked up and then tightened it back up after I mounted it back to the intake manifold.

How did your SRS issue pan out?

...Lee

Post by **confused_al** » 29 Mar 2009, 18:44

Ozark Lee wrote:...the carbon clog in the hole above the valve is like concrete...

The EGR pipe on my truck was so clogged and hard to clean (about 10" long and twisted like a snake). Luckily, it all melted away after soaked overnight in high concentrated degreaser ("Oil Eater" got from Costco).

Post by **MadeInJapan** » 29 Mar 2009, 18:57

Ozark Lee wrote:How did your SRS issue pan out?
...Lee

Funny you would ask... I got a clockspring to replace the driver's side and just before removing the old and putting the new one in, I decided to read the codes again- the code for the driver's side airbag was gone. Probably connecting the airbag and disconnecting it several times made a good connection. So, I cleaned the connectors with contact cleaner. Then, I went and did the same thing with the passenger side airbag connector, reset the codes and the SRS light went out and hasn't come back on again- Joy of joys! Nothing beats a free repair! Oh, I do have a used but in good shape clockspring for a '93-'95 850 however, if anyone needs one.

Post by **wheelsup** » 31 Mar 2009, 21:43

Wait a second, I just checked my PCV it's clear but still smoking out of the dipstick, could this be my problem?

Man I wish I would've known to check that while my manifold was off! Crap!

Post by **wheelsup** » 31 Mar 2009, 21:54

Reading thru that writeup on Volvospeed I wonder if it would just be easier to take the intake manifold off?

coedwards · Post by **coedwards** » 27 Jun 2009, 14:01

I just finished a complete PCV replacement... the car was due and I had smoke from the crankcase on idle. While I had the manifold removed, I cleaned it out well, along with the throttle body, the positive temp coefficient nipple, the ports that feed the oil trap, and just about anything else I could access with brushes, rags, and carb cleaner. Surprisingly, everything went well with the exception of me forgetting to reconnect the electrics to the throttle body. Now, I no longer have any smoke whatsoever from the crankcase at idle.

Following the instructions on this page, I should have been able to see and clean out the EGR manifold hole. I simply cannot find any such hole in the manifold of my car. I do, however, have two holes into the manifold (arrows in my picture) about 90 degrees (clockwise when facing the opening to the manifold) from the EGR hole shown in your picture. I cleaned them out well, though they were really just barely dirty. Should I be looking elsewhere for the EGR and the EGR manifold hole?

Thanks in advance... this forum is an enormous help

1998 V70XC 107,000 miles

Post by **Ozark Lee** » 27 Jun 2009, 16:02

Should I be looking elsewhere for the EGR and the EGR manifold hole?

Some have EGR and others don't. Two of my three don't have it. If you have EGR and you serviced the PCV then you would have had to deal with getting the valve off of the bottom of the intake manifold just behind the throttle body. It sounds like you don't have EGR.

...Lee

coedwards · Post by **coedwards** » 27 Jun 2009, 16:05

Thanks, Lee. I appreciate the help. Chris

Post by **powaqa** » 01 Oct 2009, 10:30

Just completed the EGR cleaning yesterday (@127K) and thought the attached picture might help with wrenching out the 8mm hidden bolt on the valve. A midwell socket would have helped but we managed to get enough of a shallow well on it (and a hair less would've = fail) once the wrench angle was figured out.

: 94 850 EGR valve bolt removal.jpg (38.27 KiB) Viewed 33360 times