EGR tubes

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juiceman
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Joined: Tue Jul 23, 2002 10:03 am

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Had a chance to really read thru the repair manual this weekend and found something that might help my clunk when the torque converter disengages

Have read some new threads that the tubes on the EGR valve may get clogged. Can these tubes be cleaned or do they need to be replaced? Is there a safe method to clean the EGR?

Any help would be appreciated. Do alot of DIY and always learning. Could tinker but figured it would be safer to ask first.

Thanks for any help!


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Q451990
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You're absolutely right about an EGR system creating a "clunk" when it's not working correctly. I had some corrosion on the EGR control solenoid electrical connections that prevented the entire system from working. After cleaning it I noticed that a very small clunk in the differential went away at low speeds (probably the 2->3 shift but I don't remember for sure). In any case I even tried unplugging the solenoid and sure enough the clunk came back - and it worked this way every time, not just a concidence.

Have you checked the EGR system for operation? You can do this by feeling the bottom of the valve while reving the engine. The valve should lift and flutter in a certain RPM range... around 1500-3000, but I don't remember for sure. You can also push up on the valve at idle and check to see if the idle speed drops dramatically or stalls. If not it's a sure sign something's clogged.

Heath

Professor_Mike
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You can clean the EGR tubes by removing them and scraping the carbon out. The carbon will be at the intake end of the tubes.

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slaughtermimms
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Q451990 wrote:You're absolutely right about an EGR system creating a "clunk" when it's not working correctly. I had some corrosion on the EGR control solenoid electrical connections that prevented the entire system from working. After cleaning it I noticed that a very small clunk in the differential went away at low speeds (probably the 2->3 shift but I don't remember for sure). In any case I even tried unplugging the solenoid and sure enough the clunk came back - and it worked this way every time, not just a concidence.

Have you checked the EGR system for operation? You can do this by feeling the bottom of the valve while reving the engine. The valve should lift and flutter in a certain RPM range... around 1500-3000, but I don't remember for sure. You can also push up on the valve at idle and check to see if the idle speed drops dramatically or stalls. If not it's a sure sign something's clogged.

Heath


My question is would the tubes being clogged, cause the Q to not pass inspection?????????/:confused:

Q45tech
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Absolutely, lack of correct EGR levels will cause the NOx readings to rise!

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Mayhem_J30
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could also be a combo of bushings and mounts needing replacement. The EGR looks pretty difficult to get to so I would try it last.

juiceman
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Joined: Tue Jul 23, 2002 10:03 am

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Just getting vibration problems resolved but planned on doing the EGR tubes next. Bought a flex drive scoket to make it easier to get at the screws holding the tubes on.

Anyone have experience doing this without pulling the upper plenum?

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Mayhem_J30
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Sorry for sending you to another site, but read this:http://www.ttzd.com/tech/egrtech.html

VimyJ
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Joined: Wed Jul 24, 2002 6:09 pm

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juiceman wrote:Just getting vibration problems resolved but planned on doing the EGR tubes next. Bought a flex drive scoket to make it easier to get at the screws holding the tubes on.

Anyone have experience doing this without pulling the upper plenum?


I haven't had the pleasure but it looks like a total PIA to get at.

juiceman
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Joined: Tue Jul 23, 2002 10:03 am

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Mayhem, great resource

Thanks!

VimyJ
Posts: 1969
Joined: Wed Jul 24, 2002 6:09 pm

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juiceman wrote:Mayhem, great resource

Thanks!
The 300zx sites are full of useful info for us J30 types.


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