Question about 1997 Subaru Outback

1 Answer

EGR Flow Malfunction, and sometimes a Cylinder 4 Misfire.

My 1997 Subaru Outback is throwing a P0400 CEL code, along with a P0304 CEL Code. It drives perfectly fine, but on start-up after sitting for a couple hours, the subie sounds like its gasping for air or something. About 2 weeks ago, I was running low on coolant and didnt know it, so my engine maxed out at 288 degrees F before the coolant started leaking/ exploding. Thats when all these other problems started. First I just got the P0400 CEL Error Code --> which is an EGR Flow Malfunction, and recently, I'm also getting a P0304 CEL Error Code --> which is a cylinder 4 misfire. I think the EGR Flow Malfunction has something to do with that one. Any ideas or good sites to check out?

Posted by on

Ad

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    President:

    An expert whose answer got voted for 500 times.

  • Master
  • 1,623 Answers

How does the oil look? Is it milky or is there any discoloration? Is any moisture or steam vapor coming out of the exhaust pipe? The EGR fault is most likely being triggered from the cylinder missfire. Sounds like you might have a head gasket blown, and/or a cracked or warped cylinder head from the overheating.
You can run a compression test to help determine this.
Good luck...i hope this helps you troubleshoot the problem.

Posted on May 09, 2009

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of.(from cars to computers, handyman, and even drones)
click here to download the app (for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Ad

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

2 Answers

99 maxima ran till it was parked now it turns over will not start gave code p0400 any ideas


The fault is somewhere around the EGR valve - probably the EGR valve or the throttle position sensor.

Before replacing any sensors try removing and cleaning the EGR.

Here's a Youtube link that may be of help to you:

1999 maxima egr Google Search

This link explains about the EGR:
P0400 Exhaust Gas Recirculation Flow Malfunction

CEL code P0400 EGR Flow Malfunction

Mar 27, 2016 | Cars & Trucks

1 Answer

What does the codes mean po1296 po411 po304


The first fault code do you mean p1296 if so that is a cooling system malfunction you will need to check the temperature sensor.

The fault code p0411 is a Secondary Air Injection System Incorrect Flow Detected

And the p0304 fault code is a misfire detected on cylinder 4 possibly a coil pack maybe a plug

Apr 15, 2015 | Cars & Trucks

1 Answer

Mercedes benz e 320 1998 model engine light code p0400


code p0400 refers to exhaust gas recirculation(EGR) system---flow malfunction.===causes---hose leak/blockage--basic setting not carried out (if applicable)---wiring---EGR valve ---EGR solenoid---ECM
check out the valve and solenoid.

Apr 29, 2014 | 2005 Mercedes-Benz Mercedes Benz E320 Cdi

1 Answer

Codes,p0304,p0483


P0304 Cylinder #4 - Misfire Detected
P0483 Cooling Fan Rationality Check Malfunction

Mar 21, 2014 | 2001 Subaru Outback

2 Answers

P0303 p0304


You'll have to get someone to check the spark and injector on cylinders 3 and 4.
Code 303 is for loss of power on cylinder 3 and code 304 is the same for cylinder 4. The most common causes are lack of spark or fuel.
Once the problems are fixed the codes will need to be erased with a scanner or code reader.

Jun 11, 2013 | Subaru Cars & Trucks

1 Answer

PO400 check engine light is on seems to run normal what to do?


P0400 - Exhaust Gas Recirculation Flow Malfunction
The exhaust gas recirculation (EGR) valve is vacuum controlled valve that regulates the amount of exhaust gases that re-enter the cylinders. The powertrain control module (PCM) determines how much based on engine load, temp, and other conditions. If the PCM detects that the amount of exhaust gases entering the cylinder were insufficient or non-existent, this code is set.

No symptoms will likely be noticed by the driver other than the MIL (malfunction indicator lamp). However, non visible symptoms will be increased combustion temperature and increased Nox emissions. A code P0400 may mean that one or more of the following has happened:
- Plugged EGR passage which restricts the flow of exhaust gasses
- Faulty EGR solenoid
- Faulty EGR solenoid wiring/harness
- Vacuum lines damaged/disconnected to the EGR valve solenoid or to the EGR valve
- Faulty EGR valve

Check it and keep us updated.

Oct 07, 2011 | 1997 Mercury Villager

2 Answers

I connected a scan tool to my 1997 mazda 626 and I got 3 fault codes P1407,P0303,P0171please help


My advise is to look at what moistcabbage had to say about your problem. Then I will add a little advise:
Put the P0171 on hold until you have a verified fix for the other 2 codes. Here's why:
.
A misfire causes raw fuel and air to be shoved down the exhaust as an unburned mixture (After all. that's what a misfire is.) This can cause the free oxygen level in the exhaust to rise and cause the lean code (P0171) From the EGR code that you have, I can tell that you have the 2.0L engine in your car. (This is not a valid code for the 2.5L) In this case, moistcabbage is sort-of correct. Thiscode actually indicates that the EGR valve does not move when the computer commands the EGR to open. (Which SHOULD also be producing a P0400 code, which is EGR no or low flow.) If P0400 is not present, then chances are that this is caused by the EGR sensor "lying" to the computer and telling it that the EGR is not opening when it really is. However, it also may be telling the truth and the computer just hasn't picked up on the low flow issue yet. Anyway, if the EGR is not moving, it could be caused by a vacuum leak, which will also cause your P0171code.
The logical order of this would be to check for obvious causes of misfire like the spark plug, wire, coil, and fuel injector and correct as necessary. Also check the EGR system out to find out what the cause of the EGR not moving code is. (And repar as necessary) Then clear the codes and drive the car to see if the P0171 code returns. If P0171 returns and the other codes stay gone, then you will have to check into oter possible causes of the lean code. Otherwise, I would not waste any time checking into a lean condition at all before the other two codes are confirmed fixed.

Mar 11, 2011 | 1997 Mazda 626

1 Answer

I HAVE A PO400 CODE ON MY 1997 MADZA MILLENIA I WANT TO KNOW HOW I CAN FIX THAT


DTC P0400 - Exhaust Gas Recirculation Flow Malfunction
The exhaust gas recirculation (EGR) valve is vacuum controlled valve that regulates the amount of exhaust gases that re-enter the cylinders. The powertrain control module (PCM) determines how much based on engine load, temp, and other conditions. If the PCM detects that the amount of exhaust gases entering the cylinder were insufficient or non-existent, this code is set.

No symptoms will likely be noticed by the driver other than the MIL (malfunction indicator lamp). However, non visible symptoms will be increased combustion temperature and increased Nox emissions.

A code P0400 may mean that one or more of the following has happened:
Plugged EGR passage which restricts the flow of exhaust gasses
Faulty EGR solenoid
Faulty EGR solenoid wiring/harness
Vacuum lines damaged/disconnected to the EGR valve solenoid or to the EGR valve

If need additional details, feel free to Contact Us.

Hope this helps; also keep in mind that your feedback is important and I'll appreciate your time and consideration if you leave some testimonial comment about this answer.

Thank you for using Fixya, and have a nice day.

Dec 19, 2010 | 1997 Mazda Millenia

2 Answers

Missing, stalling Pontiac Sunfire


The OBD II code for P0400 is Exhaust Gas Recirculation Flow Malfunction.
I'm sure the only thing you have left is you may have to replace the EGR valve or check for any leak from the vaccum lines going to to EGR valve.

Jun 01, 2009 | 1997 Pontiac Sunfire

Not finding what you are looking for?
Cars & Trucks Logo

820 people viewed this question

Ask a Question

Usually answered in minutes!

Top Subaru Experts

yadayada
yadayada

Level 3 Expert

76846 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22246 Answers

Ronny Bennett Sr.
Ronny Bennett Sr.

Level 3 Expert

6918 Answers

Are you a Subaru Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...