Wanted How to test EGR valve on 95 Explorer

[jmrich6]

How do you test an EGR valve on a 95 Explorer?

Ran OK before, except the gas mileage was going down hill, then we took the top half off to replace the lifters & pushrods. It now runs real rough & the "check guage" light is on. Also, when we take the vacuum hose off of the EGR valve, nothing changes & there is no vacuum (suction).

 

[1998Exp]

You can test the EGR valve by applying vacuum from a hand vacuum pump. As it opens, the idling will get unsteady, and with the valve fully open, will probably stall.

However,EGR valves rarely fail. What makes you think it's the source of your problem? EGR is not applied at idle, so the absence of vacuum is normal.

If I am not mistaken, a 95 model will be OBD-1, which does not have extensive diagnostics, but there will still be a code for the EGR system if that's the problem. It's very simple to read OBD-1 codes. All you need is a paper clip and a test light; no scanner required.

 

[1998Exp]

If you don't have a vacuum pump (probably a good idea to buy one - they are cheap and versatile...), the poor man's trick is to plumb manifold vacuum into the EGR. Takes a piece of tubing and perhaps a 'T' fitting.

 

[jmrich6]

Thank you! I thought that might be the problem because it has some of the symptoms of a bad EGR valve. Bad gas mileage, rough idle. I had my brother in law bring up his tester and it said it had a emissions problem.

 

[juancho1970]

did that increase your gas mileage.