Scooby96 Posted July 30, 2009 Share Posted July 30, 2009 96' Outback 2.5L 163,000 Auto Last couple of months I have had trouble with hard starts. At start it will act like it is going to choke out (around 400-500 rpm) then it will rev up to 2000-3000 rpm before it idles somewhat normally (still low aroun 700-800 rpm). As I am driving I will completely loose power (no matter the speed) erratically for about 5-10 sec upon which it will recover and run fine. Sometimes it will just do it once and other times it comes in series of power losses. Sometimes the power loss causes the car to stall and other times it will continue to run. Exhaust smells like 100% gasoline and I'm getting poor gas mileage. Went to Auto zone to get my codes puled and they gave me a print out indicating blocked EGR valve/passage and possibly MAF sensor malfunction. The EGR valve has been continually dirty in the past few months, I have cleaned it multiple times but I think it is still working because I can always see a small hole through the crud from which it looks like it is still opening and closing. Could some other problem be causing excessive build up on the EGR? Any thoughts? Work done in the past 6 mo.: -New PCV -New fuel filter -Cleaned EGR (multiple times) -Air filter -Cleaned MAF -Cleaned intake -New coolant temp sensor -New Alternator Link to comment Share on other sites More sharing options...
OB99W Posted July 30, 2009 Share Posted July 30, 2009 Most of what you've described indicates that the air/fuel mixture is excessively rich. The MAF might be bad (cleaning doesn't always resolve the problem). Also, a defective fuel pressure regulator could cause the pressure to be too high, or be allowing raw fuel to enter the intake via vacuum hose due to a ruptured diaphragm. There are other possibilities. Rather than providing the trouble code definitions, do you have the actual codes (Pxxxx)? Link to comment Share on other sites More sharing options...
Scooby96 Posted July 30, 2009 Author Share Posted July 30, 2009 the codes are P0400 and P0100 Link to comment Share on other sites More sharing options...
OB99W Posted July 30, 2009 Share Posted July 30, 2009 P0100: It could be a wiring or connection problem, although a bad MAF itself isn't unusual. Try moving the wiring at the MAF while running and see if the conditions change. You could also see how the engine runs with the MAF disconnected. See http://www.ultimatesubaru.org/forum/showthread.php?t=101117 for some more info. P0400: Assuming that the EGR valve itself is clean and operating correctly, have you also checked/cleaned the EGR intake and head passages? Link to comment Share on other sites More sharing options...
Fairtax4me Posted July 30, 2009 Share Posted July 30, 2009 (edited) Ive got the P0100 in the Legacy I just bought and have the same random power loss/ stalling problem. I've traced it to what I'm fairly certain is an internal break in the MAF sensor. I haven't replaced it yet so I'm not 100%(I'm about 99.5% sure though) but I should know by Monday since I've got a trip to the JY planned for this weekend. Check to make sure none of the wires are pinched or broken before replacing the sensor though. A rich mixture will lead to excessive buildup in the EGR valve. Take the valve off and clean it as best you can with a tooth brush. Get out as much of that buildup as you can. You might also need to remove the intake manifold and clean the ports in there as well. edit: just realized it was my thread OB99W linked to. Edited July 30, 2009 by Fairtax4me Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now