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EGR flow malfunction EJ25 won't start


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It cranks over to beat the band, but won't start. I've checked for spark, fuel flow, timing belt, crank sensor, cam sensor. Just got a friend to check the trouble code and it says P0400, which is EGR flow malfunction. Could this cause it to not start? Any suggestions for likely cause or first troubleshooting steps?:banghead:

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I seriously doubt it.

 

How did you test the cam and crank sesnor.

How did you check for spark?

How did you check for fuel flow?

Can you hear the fuel injectors clicking?

How about the temp sensor for the ECU?

 

Also GRRRRRR

how many miles on this, what transmission, and when was the last time the timing belt was changed?

 

nipper

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I thought this was in "New generation of subaru's" sorry if it's in the wrong place.

 

It's a 1996 Legacy Wagon 2.5GT, with 127,000 miles.

 

I checked the sensors with a multimeter, the resistance was 1.9 Kohms when I turned the engine over with a breaker bar I got a voltage hard to say how much since it varied greatly, but I thought I saw 35 mV.

 

I checked for Spark by pulling the wires and putting a new plug in the wire, then grounded the plug and turned it over. I didn't see a huge spark but it was consistent.

 

I also checked the primary and secondary coil resistances and they were in spec.

 

For fuel flow, I pulled the fuel hose going from the filter to the injector and turned the key to on and it gushed fuel.

 

I don't know how to listen for the igniters with all the noise of the starter going - any suggestions. And I haven't checked the temp sensor for the ECU, I'll take a look into it.

 

Thanks!!

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I seriously doubt it.

 

How did you test the cam and crank sesnor.

How did you check for spark?

How did you check for fuel flow?

Can you hear the fuel injectors clicking?

How about the temp sensor for the ECU?

 

Also GRRRRRR

how many miles on this, what transmission, and when was the last time the timing belt was changed?

 

nipper

 

I thought this was in "New generation of subaru's" sorry if it's in the wrong place.

 

It's a 1996 Legacy Wagon 2.5GT, with 127,000 miles, Automatic transmission, and the timing belt was change about 8 months ago.

 

I checked the sensors with a multimeter, the resistance was 1.9 Kohms when I turned the engine over with a breaker bar I got a voltage hard to say how much since it varied greatly, but I thought I saw 35 mV.

 

I checked for Spark by pulling the wires and putting a new plug in the wire, then grounded the plug and turned it over. I didn't see a huge spark but it was consistent.

 

I also checked the primary and secondary coil resistances and they were in spec.

 

For fuel flow, I pulled the fuel hose going from the filter to the injector and turned the key to on and it gushed fuel.

 

I don't know how to listen for the igniters with all the noise of the starter going - any suggestions. And I haven't checked the temp sensor for the ECU, I'll take a look into it.

 

 

Thanks!!

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Get yoursel a haynes manual, not all sesnors are checked by resistance.

You can hear the fuel injectos click. If you cant hear them click you need to check the cam and crank sesnors for AC output with an analog meter as the engine turns. There is a pulse pattern described in the haynes manual.

The weak spark is troublesome. It should be a strong blue spark.

Start by checking those two sensors. Another possability is the engine temp sesnor for the TCU but i want to rule the other two out first.

 

nipper

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Get yoursel a haynes manual, not all sesnors are checked by resistance.

You can hear the fuel injectos click. If you cant hear them click you need to check the cam and crank sesnors for AC output with an analog meter as the engine turns. There is a pulse pattern described in the haynes manual.

The weak spark is troublesome. It should be a strong blue spark.

Start by checking those two sensors. Another possability is the engine temp sesnor for the TCU but i want to rule the other two out first.

 

nipper

 

Thanks for the feedback! Got the Haynes manual. I checked the sensors (camshaft and crankshaft) with a voltmeter as follows: I turned over the engine with a socket and breaker bar and monitored the voltage. It did have a pattern, but the voltage was hard to read. It looked like I got about 35 millivolts at times. Guess I could do it slower to see for sure, but since I saw a voltage change I assumed they were ok.

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Thanks for the feedback! Got the Haynes manual. I checked the sensors (camshaft and crankshaft) with a voltmeter as follows: I turned over the engine with a socket and breaker bar and monitored the voltage. It did have a pattern, but the voltage was hard to read. It looked like I got about 35 millivolts at times. Guess I could do it slower to see for sure, but since I saw a voltage change I assumed they were ok.

 

yes. Its not the number our looking for, but the heart beat.

 

The weak spark has me concerned

 

 

nipper

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  • 4 weeks later...

Well I decided to pull the plugs and they were badly worn (big gaps), so I replaced them with NGK iridiums. It still wouldn't start until I shot some starting fluid in the manifold and closed it up. Then she fired up and has been running pretty well. Although I see that after a little driving I've got the old P0400 code pending. So, I still need to do some work on the EGR system. Prior to the plug change I pulled the EGR valve and it had a fair amount of soot on it so I cleaned it good. It held a vacuum well. I checked the solenoid and it appears to operate fine. I have no idea how the back pressure transducer works so if someone could tell me about that it would be great.

I did a quick check and advanced the throttle quickly and held it, it looks like it moves about a 1/4 inch and stays there. If I move it more it moves about 1/2 inch and stays open. At idle it appears to be closed. Is that typical?:slobber:

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I think I found the problem. There's a plug in the little pipe that runs from the manifold, to which the EGR valve is attached, to the bottom of the back pressure transducer, through a rubber tube. I've been trying everything to clear it. Any ideas? Can you remove it? I loaded the picture into photos search on "EGR pipe". I Haven't figured out how to add them in the message yet.

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