So, what does everyone do with all the crappy vacuum lines that are rotting away?

I'm chasing EGR codes with the truck.  I'm thinking that one of the causes are the near-30 year old vacuum lines rotting away.  I know that a few of them snapped as I was changing the injectors, and I replaced and/or patched them as necessary.

I'm thinking of getting some stainless tubing and just running that for everything.  Hard connections for everything on the engine, a rubber connecter on one side for the stuff going to the AC and other such crap.  4 foot of 316SS is $20 from McMaster

I think most people just replace them every 25 or 30 years

Chances of me owning the same car for the next 20 years is 0, so if I replace anything I always go with rubber. Cheap and easy. It'll probably outlive the car at this point. 

I buy hose by the 25' roll from Rockauto. 

Replacing vacuum hoses definitely helps.

What species truck is it?  I have found that GM trucks are sensitive to exhaust backpressure.  They use exhaust pressure on the EGR inlet side to balance the flow vs. the vacuum operating the diaphragm.  Upshot is, if you have a free flowing exhaust, the EGR valve doesn't work anymore.

Fords used a differential pressure sensor to sort of do the same thing.  It has a spectacularly high failure rate.

In reply to Pete. (l33t FS) :

93 F150 4.9L

In reply to Mr_Asa :

Ah yes.  The DPFE, if it isn't new, is probably bad.  If it IS new, it merely might be bad.    It's been a long time since I've tested one, so I couldn't tell you the 15 second test off the top of my head.

WillG80 said:

Chances of me owning the same car for the next 20 years is 0, so if I replace anything I always go with rubber. Cheap and easy. It'll probably outlive the car at this point. 

You need to fall in love with a car. You'll do things that make absolutely no sense.

I replace the obviously bad ones, and then reset the codes and check again.  I'm chasing an EVAP code on my Crammit right now.  I replaced a hose and need to reset the codes, but I think it still might have an issue.  I was working on the ignition switch today and found a precariously unprotected wire near the exhaust, plug wires and steering shaft.  Once I get it fired up, I will have to look into that in more detail too.  Old cars are a constant maintenance concern due to things that are old and worn out. 

I replace them with silicone. 

Pete. (l33t FS) said:

In reply to Mr_Asa :

Ah yes.  The DPFE, if it isn't new, is probably bad.  If it IS new, it merely might be bad.    It's been a long time since I've tested one, so I couldn't tell you the 15 second test off the top of my head.

Strangely, at least up till the point I rebuilt the engine, I've only ever had one EGR code pop up and that was ~10 years back.  Sometimes you get lucky 

Currently have codes 332 and 538

I loved the days when you could work on OBD1 stuff and just pull all the vacuum lines out and cap them - no codes.   First thing I would do on any DSM I had is get rid of every vacuum line, block the EGR, 3" straight exhaust off the turbo, put in a manual boost controller, and get back to the party.  

In reply to Mr_Asa :

You think you've got it bad? Imagine a V12!!!!! Then add that the computer is in the trunk and a rubber hose has to go all the way back there.   Nope you can't just pull it through either.  I pulled the whole interior including carpets and insulation. And still wound up having to cut it out in pieces. 
   I like the idea of stainless steel neatly bent line to replace the spaghetti look that rubber hose looks like.  

93gsxturbo said:

I loved the days when you could work on OBD1 stuff and just pull all the vacuum lines out and cap them - no codes.   First thing I would do on any DSM I had is get rid of every vacuum line, block the EGR, 3" straight exhaust off the turbo, put in a manual boost controller, and get back to the party.  

I could make a joke here about Mitsubishis vs real cars, but that isn't too fair since Mitsubishi knew damn well what they were doing when they did the code for the 4G63 engines.

Fords had test strategies for the air pump and EGR, and they also had really good FMEM.

WillG80 said:

Chances of me owning the same car for the next 20 years is 0, so if I replace anything I always go with rubber. Cheap and easy. It'll probably outlive the car at this point. 

Cheapskates like me buy new and drive for 20 years. That made my cost of ownership $87.50 per month for a V8 4x4 1997 pickup that went to the junkyard with a beautifully running engine & trans  etc etc. etc. never once let me down.  Cost me only $1000 over a 20 year period in repairs.