Refer to this thread: https://www.dieseltruckresource.com/...d.php?t=123116

Add any advice you can think of...

I checked EVERYTHING!

If this thread was previously deleted, I'm sorry for reposting, because I am in such a rage right now I dont know if I clicked "submit"

 

Buy a hand vacuum pump with gauge from the autoparts, as cheap as around $20.
On the big line from the vacuum pump to the booster there are several small lines that tee off. Disconnect them one at a time and pump down till you find the one where the gauge creeps down.

 

You did click submit.

I removed it because a little noise from the behind the dash at shutdown it didn't seem like an emergency situation to me.

Remain calm and do what Bill said.

Don't worry, be happy.

 

Don't waste your money on the vacuum pump for this problem because it won't tell you anything. I had the same problem with the four wheel drive vacuum leaking on a 97 also. I really think what happens is the four line connection on the transfer case developes a small leak either in the connection of one of the lines themselves or maybe even in that valve. Regardless, most of the time I could get mine to hold vacuum again just by unhooking the connection and cleaning it up and rehooking it. Sometimes it took alittle wiggling of the connection with the truck running and someone watching the vents to see if the airflow changed but I always got it. If you have anymore questions about it private message me with your phone number and I would be happy to call you right away and maybe I can help. Good Luck.

 

WannaDiesel - did you move his thread to another forum or remove it altogether?

 

I've never tried this on a deisel engine, but this is what I do with a gasser. Spray the lines with carb cleaner. Just little shots. The engine will speed up when it sucks the cleaner into the engine. Don't use alot now, just a shot. The engine should rev up just a tad when you find it.

In the old days we used an un-lit propane torch, but it's can be dangerous.

 

that won't work as the vacuum is not from the engine, it is generated from the vacuum pump

 

That what I was thinking, but hey, doesent hurt to throw an idea out there. I agree a pump won't help. It will just verify a leak, not tell you where it is.

 

You guys must not have ever used a pump.
Once you find the leaking circuit you move down it till it gets to the point where it quits leaking.
Problem isolated.
Plus you can use the pump later for bleeding brakes.

 

Well, that was the problem!

I must have had low-vac since I owned the truck - cruise works 100% better now!

I cut another connector off a donor truck ('96 1500) and just tapped into the lines on my truck...

I also upgraded some of my lines... and made new "T" fittings...

I hate vacuum leaks, and this one was a pain to track down!

Thanks to everyone who helped!