Welcome to Ultimate Subaru Message Board, my lurker friend!
|Welcome to Ultimate Subaru Message Board, an unparalleled Subaru community full of the greatest Subaru gurus and modders on the planet! We offer technical information and discussion about all things Subaru, the best and most popular all wheel drive vehicles ever created.
We offer all this information for free to everyone, even lurkers like you! All we ask in return is that you sign up and give back some of what you get out - without our awesome registered users none of this would be possible! Plus, you get way more great stuff as a member! Lurk to lose, participate to WIN*!
* The joy of participation and being generally awesome constitutes winning
** Not an actual guarantee, but seriously, you probably won't regret it!
Serving the Subaru Community since May 18th, 1998!
EGR system problem
Posted 04 November 2003 - 09:54 PM
Posted 04 November 2003 - 10:55 PM
I too have been getting this code recently on my 97 OB auto.
I had it in the spring but it was a pressure / vacuum sensor that mounts to the passenger strut tower that was actually the problem. I don't know if the manuals have this sensor. It apparently "tests" the operation of the EGR, as well as provides some 'input' to the TCU. (My shifts were a little sloppy and delayed at times.. this was cured as well after the sensor was changed.)
Let me know how you make out. I haven't resolved mine. It just came back on me several weeks ago. It came on once before I was in for servicing lately. The shop didn't see anything obviously wrong. Then it came on a few weeks ago. And now twice just today.
No noticable difference in operation, although I do have a little hesitation / stumbling that I believe is carbon, but I have heard that a malfunctioning EGR can cause similar affects.
Posted 05 November 2003 - 11:16 AM
Posted 05 November 2003 - 12:42 PM
Hey Commuter, how much is that pressure/vacuum sensor you replace?
Funny thing is the car seems to run and shift fine. Watching the EGR valve when revving the engine between 2K/3Krpm it appears to be operating correctly. Maybe the ECU's circuit handling the EGR functions is faulty....
Posted 05 November 2003 - 01:11 PM
That stupid little sensor (< 1" black cube with a couple of mounting tabs, a vacuum line nozzle (or 2?) and a 3 wire connector) listed at $430 Canadian IIRC. Definitely worth shopping around for... or even trying used. It was one of the few times that I felt that a Subaru part was out of line, price wise.
For me, the telltale sign was that my shifts were "off". They seemed a bit slow... delayed... sluggish... almost as if something was slipping. Not real bad at all... and not every time, but there. This cleared up totally after the sensor was changed.
The mechanic told me that this sensor monitors the manifold vacumm and provides some "input" to the TCU's shifting algorithm. As a secondary function, it "looks" for a change in vacuum when the EGR is opened. Therefore (since it was failing), it erroneously triggered a ECL with the PO400 code (EGR malfunction).
I don't know what is going on now. I'm basically letting it develop and get worse, then I'll take it in. It's not something that I feel inclined to tackle myself, especially with colder, rainy weather setting in. The Code reader I bought in the spring is seeing it's use now.
Posted 05 November 2003 - 01:50 PM
If these repairs are not the fix you need to look at the map sensor. It monitors vacuum thus it can tell if the egr is working. If the egr is not working the map sensor tells the computer to set the egr code. There is a small filter inline on the map sensor hose it is common to fail be sure to replace it if you believe the map sensor is your problem.
As to the knock sensor code; simply replace the knock sensor. Good luck.
Posted 05 November 2003 - 09:03 PM
Posted 08 November 2003 - 11:16 AM
Also is there anyother componets that could directly affect the vacuum signal in the EGR system besides the 3 componets that are listed in the manual as the EGR system?
1 user(s) are reading this topic
0 members, 1 guests, 0 anonymous users