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Jason
05/26/2003, 03:00 PM
I've had my VX in for the EGR Tube problem, and yes, about 6 - 9 months later I've got the same sound. I'm not a big engine guy, so could someone give me directions? Does the EGR Valve sit just behind the engine, on top, passenger side? If so, where in relation to the EGR valve is the tube? I believe I see a 22mm nut under the valve and a pipe leading from it. What am I looking for? Is the tube completely gone in these cases or just slid down a pipe out of place?

Thanks,

Tone
05/26/2003, 04:51 PM
Typically the 22mm nut will come unscrewed from the EGR assembly and slide down the tube, opening up the connection. Usually all that must occur is to rethread the nut into the EGR assembly and tighten. Definitely want this to be done when the engine is cold and be very careful not to crossthread the nut. A short 22mm wrench is best for this or cut a standard one in half.

Heraclid
05/26/2003, 06:39 PM
...in case anyone else was confused, I dug this up...


EGR - Exhaust Gas Recirculation

Why would anyone want to dump exhaust back into the intake of a perfectly good engine?

Unfortunately, the internal combustion engine is not `perfectly good,' and consequently creates NOx (Nitrous Oxide) during the high temperature combustion process. NOx reacts with sunlight to create atmospheric problems such as smog and so comes into the category of 'not a good idea'.

EGR is considered a `metered intake leak' and was developed to reduce the combustion temperatures to below 2,500 degrees, the threshold where NOx is created. Not unlike putting a brick in your lavatory to lower the volume of water used, the EGR valve meters a readily available inert gas (actually exhaust gas which contains a lot of very inert Carbon Dioxide) into the combustion chamber to effectively reduce the volume. Smaller effective displacement means less fire, and less heat and thus lower temperatures, thereby controlling NOx emissions.

Obviously we don't want to `reduce' the volume of the combustion chambers (effectively reduced engine displacement) during hard acceleration, so EGR is turned off when you need full power (WOT (Wide Open throttle) conditions). At idle, the engine is very sensitive to air/fuel mixture ratios and swirl in the combustion chamber, so introducing EGR at idle is not on either. However at cruise the Fuel/Air mixture is set as lean as possible for maximum economy and this in turn generates the highest temperatures, and so the EEC-V uses these conditions to inject exhaust gas into the inlet manifolds to reduce emissions.

Jason
05/26/2003, 08:51 PM
Thanks for the good info. So, do I have it identified correctly? Behind the engine on the passenger side, up high?

Thanks,

VehiX
05/26/2003, 09:25 PM
You'll want to talk to dallas4u about this one :)

Anita
05/27/2003, 03:35 PM
Funny you talk about this now... my service rep just recommended that we clean my VX's... built up carbon..