EGR (EVP) Closed Valve Signal Too High

[AshleyTheGreat]

Hi all,

Derek and I finally had a chance last night to play with our SnapOn MT2500 Scanner that we scored. We tested it out on both of our Town Cars and code 34 (EGR Closed Valve Signal Too High) popped up for each of us. As you can see, it indicated to check the EGR Valve Vacuum Regulator. We did and it was in the recommended 30-70 OHMS. Any ideas as to where we go from here?





As always, thanks for all the help.
Ashley

[miamibob]

Sounds like the EVP Sensor (that bad boy that sits on top of the EGR Valve). First I'd make sure the EGR Valve is clean (along with the ports) and that the diaphragm is not damaged. Then pull vacuum on the line to it. Replace the sensor, if all else checks out ok, with a MOTORCRAFT OEM sensor. Let us know what happens.....

[DerekTheGreat]

At least I think I set the multimeter on the right setting. It read something like 0.048 which I took as 48 ohms. I'll buy a vacuum pump this weekend to test out the valve and see if the car stumbles at idle. Old people owned both cars before us so wouldn't surprise me if the egr passages are all clogged up on both cars. Funny thing is her CEL isn't on, it flashed and stuff when the scanner was hooked up and also comes on when you flip the key over. I tried clearing the codes and the scanner shows code 11 which it says means no codes yet still lists code 34.

[gadget73]

Unhook vacuum from the valve to see if anything changes. You can also measure output directly on the EVP. Might not hurt to do this and then unhook the vac line. Nothing should change. Output should be per the chart:

http://www.grandmarq.net/oldfuelinjection/page35.html

I believe you ought to have the grey sensor. If its the black one, thats why it doesn't read right.

If the valve is clean and actually fully closed, you might be able to tweak it by removing the EVP and filing down the rod on the sensor. If its just way off base, then the sensor is probably dead.