Vacuum Question

[dennyge]

My 99 RAM 5.9L has a small vacuum leak as indicated by the cabin blower shifting from panel to defrost while going up hill on cruise control. This weekend, I took my son to a hockey trip (about a 4 hour drive) and noticed that while cruise was engaged the speed of the vehicle would slowly drop until I reset the cruise. I am assuming this may be due to the leak as well. Two questions:

First: Am I on the right track that this may be due to the leak?

Second: Being a shadetree mechanic, how would I go about searching for the leak?

Thanks, guys!

[jdl]

Are there any trouble codes?

[dennyge]

I have not had it scanned, but there is no CEL or flashing codes.

[jdl]

If you think there is a problem with a vacuum actuator, you can test the actuator by using a hand operated vacuum pump. I wouldn' pull anymore than engine vacuum.

This isn't a diesel, is it?

There may be a vacuum reservoir that you can check. I don't have any vacuum diagrams for your vehicle. You might follow the vac line off the cruise, to see where it goes. You can check vacuum lines by plugging one end and pulling vac on the other end.

[dennyge]

Thanks for the info, jdl. Unfortunately, when I say "shadetree mechanic" I mean more of the shadetree than the mechanic part. I wouldn't know a vacuum line from a steering wheel. How could I identify the vacuum line and cruise?

BTW--Not a deisel

[jdl]

The vacuum lines usually look like small rubber hoses.

There should be a decal under the hood, that has vacuum diagrams. You'll have to look for it.