I'm having intermittent grinding noises coming from driver side IWE. When I first heard the grinding I put the truck in 4x4 and now I am driving around in 2 wheel drive with the lines removed from the solenoid, so I am hoping the IWEs are OK. I checked vacuum at input to solenoid (22"), passenger side IWE (22"), and driver side IWE (4"). Seems like I must have a leak in my vacuum line. I tried blocking off the hoses at the IWEs and pulling vacuum at the other end of the line (output of solenoid), but my pump is junk and didn't seem to be working (I might buy a new one and retest). Is there anything else I might be missing? Does anyone know a part number for these vacuum lines or where to purchase them for a decent price? Can you buy parts of the vacuum line system or do you need to purchase the whole thing?
Thanks

 

Could be the drivers side IWE leaking.. pull vacuum on the IWE itself to be sure.

 

So, I finally got around to doing some further testing on the system and I think my original guess was incorrect. I mentioned that I was only measuring 4" on the drivers side. I tested this again but this time i also pulled the hose off the passenger side IWE and plugged it with a golf tee. As soon as I did this I could see the gauge (connected to the driver side) climb to 20". So now I am thinking that the seal on the passenger side is blown and when the system is all connected the vacuum on the drivers side is affected and at 4-5" it is sometimes engaged and sometimes disengaged, which might be why I was hearing the intermittent grinding. If anyone has any thoughts please share. I think I will buy a couple IWEs and start there.

 

Thanks for the advice. I still haven't bought a reliable vacuum pump. I suppose I should as it would probably determine which IWE or vacuum line is the problem. I am not sure why the one I was using stopped working so suddenly, they seem so simple to use. Not sure what I could have done to break it.

 

You can barrow one from auto zone loan a tool program.