96 Intrepid EGR valve meltdown

[ccundy]

Greetings,

I have a 96 dodge intrepid 3.3 v6. I suddenly got power loss (intermittent) and a very rough idle. It had code p1297 which came back as map sensor (no vacuum change at idle). I noticed that the EGR transducer was melted, like the vacuum line was blowing very hot and just melted everything. I was told that the EGR valve was bad and a hole in the diaphragm of the EGR allowed exhaust to enter the vacuum line and melt everything. I replaced the EGR assembly and every thing was good for about 5 days. I got the (Bad) power loss, without the rough idle. I checked, the transducer is again melted. The code thrown this time was for the EGR valve. I have a new EGR valve but don't want to melt another one. I have removed and checked the EGR 'tube' and am trying to get a "Hand" vacuum pump to check vacuum lines. If anyone can tell me why the EGR is sending such Hot air into the transducer I would very much like to know why.

Thanks in advance
Christopher

[AWP9521]

Check your steel EGR tubing for cracks or gasket leaks, it may be blowing the exhaust gasses onto the vacuum tubing and super heating it and sucking the hot air into the transducer.

[ccundy]

I got the vacuum gauge and checked the vacuum into the Egr. it is steady at 17 psi. after some research I realized that the tube that is 'exhausting' the hot gas is the "back pressure" line. I have tried to see what would cause the back pressure line to build such pressure and the only thing I can think of is if the catalic converter is plugged. I hooked the pressure gauge to the back pressure line and at normal temp and 2k rpm I noticed a very slow rise in exhaust pressure. very slow.

Am I on the right track, or just barking up the wrong tree.

BTW I checked the tubes and gaskets and all were in good shape.

[ccundy]

Yes, it was a clogged cata. converter. The plug was causing a buildup of pressure that exceeded what the 'back pressure' tube could handle. the tube became another exhaust pipe.