1994 PATHFINDER EGR ISSUE

[robert z.]

1994 pathfinder SE V6 3.0 liter. Failed smog because high nox reading. Egr valve works cat is good electric switch for egr is not recieving signal

[frapjap]

Welcome to NICO!
It sounds like you might have more issues. See if there are any codes you can pull from the ECU.
Here at NICO, we have Factory Service Manuals available free to members. Take a peek at the link in my signature and find the FSM for your car and you'll have all the info you'll ever need to make the repair and help you track down the potential problem.

[atraudes]

How did you determine the EGR switch isn't receiving signal? Is it throwing a code or did you bust out the multimeter?

[robert z.]

Used a multi meter. Gets 13 volts steadily at idle in park on the rack in gear revved up still 13 volts

[atraudes]

What gave you the indication to focus on the EGR valve? Is it throwing a code? Lean combustion or a defective catalytic converter can also cause a high NO condition, so that alone doesn't indicate a defective EGR system.

Any additional background, findings, or thought process you can provide can help.

[robert z.]

New cat checked egr valve and it works fine. Egr switch not getting signal

[atraudes]

Voltage is applied to the EGR switch only by the ECU, and it applies it as it sees fit, based on the operating conditions of the engine. I'd say the fact that the switch is receiving voltage is a good sign and indicates that the connection from it to the ECU is working properly. If you want to learn more about the conditions under which the ECU applies that voltage, refer to the two sections on the EGR valve and system in the FSM.