Is the elbow fitting that runs from a vacuum line to the EGR valve suppose to be rubber? On mine the end is totally melted and it won`t stay connected to the EGR. Might that be an indication that the EGR valve may be leaking causing exhaust to be heating up the top of the EGR more than normal?
It should be rubber. Replacements can be found on the HELP rack at the parts stores. You can test the EGR valve for leaks by removing the elbow and pressing upward on the diaphragm from underneath. Cap the nipple then relax the pressure against the diaphragm to see if it holds vacuum. If you feel it returning to the resting position, it's defective. 5 inches of vacuum with a hand pump will also diagnose it.
It should be rubber. Replacements can be found on the HELP rack at the parts stores. You can test the EGR valve for leaks by removing the elbow and pressing upward on the diaphragm from underneath. Cap the nipple then relax the pressure against the diaphragm to see if it holds vacuum. If you feel it returning to the resting position, it's defective. 5 inches of vacuum with a hand pump will also diagnose it.
Thanks, I found a new elbow. Pushed up on the diaphram, held my finger over the hole and it stayed in place until I let go. Installed the elbow and it looks like it`s good to go.
Well, the saga continues. I drove my car in North and East Texas this weekend at highway speeds and this morning when I was getting ready to head home this is what I found. The new elbow I installed before I left Friday was melted again. Somehow where the elbow attaches is getting hot enough to melt it.
[This message has been edited by TXGOOD (edited 10-20-2013).]
You probably have an exhaust gas leak at one of the flanges that's being directed towards the line. The diaphragm housing shouldn't get that hot on it's own.
I'm just trying to figure out how hot exhaust gases can get up through the valve but it still holds a vacuum. I don't see anything in your picture to indicate hot exhaust gases blowing on it from any thing close. If it was, it looks like it would also burn the shrink tubing, too.
The only other thing I can figure is considering the EGR mostly works at low RPM maybe the vacuum solenoid is bad causing the EGR to always get vacuum causing it to stay open during higher RPMs such as at highway speed. That would probably allow the EGR body body to get much hotter than normal.
Air doesn't pass through the valve to the solenoid, it just moves back and forth as vacuum is applied. The pintle is hollow on many of the EGR valves, so that might be the problem, but I still don't understand how heat can pass through the pintle and yet the valve still holds a vacuum. .
Air doesn't pass through the valve to the solenoid, it just moves back and forth as vacuum is applied. The pintle is hollow on many of the EGR valves, so that might be the problem, but I still don't understand how heat can pass through the pintle and yet the valve still holds a vacuum. .
I know that air doesn`t pass through the valve to the solenoid but if the solenoid is defective and it`s allowing vacuum to be constantly applied to the EGR valve, thus it remains open then the hot gases passing from the exhaust manifold to the tube at high speeds might cause the EGR valve body to heat up.
