# New EGR valve - somthing isn't right



## Agoudine (Feb 19, 2005)

I've installed new nissan Egr valve on my Altima 95. Then I've tested it as Manual suggest by opening throttle and checking diaphragm movement.
THE diaphragm DOES NOT MOVE ,just like it did not move on my old valve !
I guess something else is wrong,but what? All hoses are good, solenoid is new and also nissan. Gas milage is getting worse. Please tell me what do you think?


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## Asleep (Jan 19, 2003)

Agoudine said:


> I've installed new nissan Egr valve on my Altima 95. Then I've tested it as Manual suggest by opening throttle and checking diaphragm movement.
> THE diaphragm DOES NOT MOVE ,just like it did not move on my old valve !
> I guess something else is wrong,but what? All hoses are good, solenoid is new and also nissan. Gas milage is getting worse. Please tell me what do you think?


it wont move until about 3000 rpm and then only under a load. manually move it with your hand and see if it dies. at least then you know that the valve itself works. does the bpt(backpressure transducer) work? have you checked all of the vacuum lines in that area?


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## jserrano (Oct 27, 2004)

Slightly underneath the EGR solenoid valve, and alongside the EGR valve, sits the EGR-BPT (Backpressure Tranducer). The BPT senses the exhaust back pressure. If it is low is will not let the EGR valve operate. It does that by venting to the atmosphere the commonly shared vacuum hose of the EGR valve.

If you follow the hose underneath the BPT, it will lead to a cast iron piece over the throttle body. That is where it picks up the exhaust pressure. Unbolt and pull off this bronze-looking exhaust pickup tube and you will notice a small opening at the end. It is probably all clogged up (or nearly) with carbon deposits. Since it is clogged up, the BPT "thinks" there is no exhaust backpressure and will forever keep the EGR valve from operating properly.

You should indeed be able to feel the EGR valve move when you slowly and manually move the throttle up and down around the 2000 rpm range. If it takes more rpm to move the EGR valve then this sugguests that the above mentioned port is somewhat clogged up.


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## WhiteFox (Sep 4, 2002)

Would that pipe being clogged throw a computer code on it?
I have crap for mileage right now and that's what comes up.


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## Agoudine (Feb 19, 2005)

Thanks guys.
I believe I know what parts you are talking about. I'll do it.


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## jserrano (Oct 27, 2004)

WhiteFox said:


> Would that pipe being clogged throw a computer code on it?
> I have crap for mileage right now and that's what comes up.


It is possible to get a code depending on how clogged up it truly is. But check all the other EGR components to make sure.


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## ucdechem (Dec 20, 2005)

I'm having the same problem, (my EGR valve works fine, but it simply does not operate at any engine speed). I've cleaned the tube you spoke of, and exhaust gas does indeed flow from it, however the EGR valve still receives no vacuum. Would you attribute this to the BPT valve or more likely the solenoid? I've tried blowing into a hose connected to the BPT valve (where the exhaust gas would go), but I cannot blow at all. Any ideas would be greatly appreciated at this time.


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## jserrano (Oct 27, 2004)

ucdechem said:


> I'm having the same problem, (my EGR valve works fine, but it simply does not operate at any engine speed). I've cleaned the tube you spoke of, and exhaust gas does indeed flow from it, however the EGR valve still receives no vacuum. Would you attribute this to the BPT valve or more likely the solenoid? I've tried blowing into a hose connected to the BPT valve (where the exhaust gas would go), but I cannot blow at all. Any ideas would be greatly appreciated at this time.


Remove the bottom hose from the EGR-BPT and closely take a good look at it while flexing it. If it feels spongy then replace it. Mine actually was bad. It was spongy and had a nice little hole in it which obviously had an effect on the EGR system.


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## ucdechem (Dec 20, 2005)

The hose connecting the brass tube to the BPT valve on mine was real spongy, also. I had replaced that and cleaned out the brass tube, but it still hadnt worked. For some reason, I didnt think of spraying cleaner in the BPT valve, I'll try that. Thanks


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## jserrano (Oct 27, 2004)

Remember that the EGR solenoid valve actually is used for both EGR and carbon canister. A leak in the carbon canister EVAP system could potential be felt back on the EGR.

You should backprobe the light green wire on the EGR solenoid valve. It should change from zero (0) to battery voltage and back as you throttle up and down. Also, with the ignition key out, you should check for resistance between the two terminals of the EGR solenoid to see if it is open. Alternatively, you could jumper the battery to this solenoid and it should click.

Let us know what you've found.


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