Modified XJ Cherokee Tech XJ (84-01)
All modified tech questions. If it modifies your XJ beyond stock parts ask it here.
Sponsored by:
Sponsored by:

Creating/BuyingVacuum Lines

Thread Tools
 
Search this Thread
 
Old Jan 7, 2017 | 09:35 PM
  #1  
tfritz123's Avatar
Thread Starter
Newbie
 
Joined: Aug 2016
Posts: 16
Likes: 0
From: Worcester County, MD
Model: Cherokee
Default Creating/BuyingVacuum Lines

Jeep is a: 1995 Cherokee SE(?) 4.0L Automatic 212,000 miles

Yesterday I did the injector swap that we all know about. All went smooth and it runs (technically). The Idle is bad and will occasionally stall at idle, not under throttle. While I was doing this I broke 3 vacuum lines I know of, Fuel Rail Pressure Regulator line, the small one on to of the intake maifold, and one on the back of the engine bay which i think leads to the MAP. This is due to me not paying attention and the plastic is very fragile.

I believe these are causing problems with the idle and I want to place them ASAP, like tomorrow if possible. What is the best was about replacing these line to get the engine back to how it should be?

Can I just create my own, do internal diameters matter, or
should I buy the new?

PLEASE I AM BEGGING someone to post a link to vacuum lines. I have been searching but after the past 2 weeks working on the jeep I just cant seem to find things anymore.

If anyone has any other two cents on things to consider after the swap let me know
Reply
Old Jan 7, 2017 | 10:11 PM
  #2  
cliffy's Avatar
Senior Member
 
Joined: Sep 2014
Posts: 739
Likes: 6
Year: 2012
Model: Grand Cherokee (WK)
Engine: 3.6 V6
Default

It is a vacuum line, I broke one doing something and used a piece of black rubber hose and hose clamps to replace it. Depending on location it could work as a band aid. Autozone has access to diagrams for vacuum systems for free.

Last edited by cliffy; Jan 7, 2017 at 10:24 PM.
Reply
Old Jan 7, 2017 | 10:39 PM
  #3  
fb97xj1's Avatar
CF Veteran
 
Joined: Dec 2015
Posts: 3,038
Likes: 338
From: PA
Year: 1997
Model: Cherokee
Engine: 4.0L
Default

Parts store carry various sizes of vacuum line, including elbows (hard and soft) and "T" fittings. they also sell rubber hose. Rockauto sells this stuff as well. Near the top of the page next to the little cart icon, go to Tools and Universal Parts > Hoses/Pipes/Clamps > Vacuum Hoses. They might even carry factory style lines and hoses for your year, you will have to check. Go to Parts Catalog and scroll down to Jeep. There is also ebay. Just match the inside (or outside diameter) with whatever you have now. Some list both.

In a pinch i have used heat shrink to hold the broken lines together, using a heat gun. Way quicker than a booklet of matches. A section of rubber hose with an inside diameter that matches the outside diameter as the vacuum line also works. A little snug is best. Some wrap the lines in electrical tape. This should be used as an emergency road side repair only to get to wherever it is you need to go. I have even seen drinking straws spliced in, held fast with zipties (the small ones). Again, an emergency roadside repair.

If you cant find something, sometimes you have to get creative.

Last edited by fb97xj1; Jan 7, 2017 at 10:41 PM.
Reply
Old Jan 8, 2017 | 08:29 AM
  #4  
bad_idea's Avatar
CF Veteran
5 Year Member
 
Joined: Apr 2016
Posts: 1,820
Likes: 60
From: Pasquotank, NC
Year: 1990
Model: Cherokee
Engine: 4.0
Default

I replaced most of the hard plastic vacuum lines under the hood with vacuum hose. Identify the size that fits on the nipples correctly and replace with that size. I would suggest making a good guess, then go to the auto parts store and ask for 2" of each size close to what you think it is. Vacuum lines are measured in 1/32 of an inch, so it is a PITA to identify the CORRECT size. Use your 2" sample pieces to identify what line needs to be what size and length. Write a list. Replace every vacuum line, they are all due. Go back to auto parts store and buy that list. Its a PITA, but well worth it. Replace lines one at a time to avoid mixing them up.
Reply
Old Jan 8, 2017 | 10:24 AM
  #5  
PNWjeeper's Avatar
CF Veteran
 
Joined: Feb 2012
Posts: 1,206
Likes: 2
From: Southern Oregon
Year: 1990
Model: Cherokee
Engine: 4.0
Default

Just for my own curiosity, did you reset the computer after replacing the injectors?
Reply
Old Jan 8, 2017 | 10:41 AM
  #6  
tfritz123's Avatar
Thread Starter
Newbie
 
Joined: Aug 2016
Posts: 16
Likes: 0
From: Worcester County, MD
Model: Cherokee
Default

At first I wanted to avoid resetting the pcu because I didn't want a rough idle, however I did have a rough idle so I did reset that computer (I think). Other posts have state I will have a bad idle for about 50 on-off running cycles for the computer to collect data and make adjustments as necessary. That's why I want to get the vacuum leaks fixed asap and I'll probably reset it again.

I have noticed great throttle respose and when it is cooperating it idled great and at cruising speeds it purrs like my Acura.

Thank you you everyone for you responses and not accosting me for breaking things lol. I'll update this after I fix the lines
Reply
Old Jan 8, 2017 | 01:48 PM
  #7  
tfritz123's Avatar
Thread Starter
Newbie
 
Joined: Aug 2016
Posts: 16
Likes: 0
From: Worcester County, MD
Model: Cherokee
Default

Okay here is an update like promised:

Went to advanced auto and bought >>5/32'' Outer Diameter (OD)<< emissions tubing and all sorts of rubber connectors so i wouldn't have to make the trip twice. Got home and luckily I had enough factory tubing left to simply use straight rubber >>5/32'' Inner Diameter (ID)<< rubber connection to bridged the connections so the vacuum/pressure was restored. Cost me about $10 to fix.

Update to the Injectors:
After fixing the vacuum leaks/broken connection I immediately noticed a massive difference in idle, pretty much normal. Very smooth. Under driving conditions everything was going well and no Check Engine Lights (CEL). Only thing i did notice is the initial starting is still rough and I need to give it gas to start but once its started it is fine. Went around the block and did some donuts (its icy here right now) and it didn't stall and everything was running well. Also the system has been started about 20 times since reset so it may still be learning and not its different again so it may regulate itself.

Moral of this write up is that those vacuum lines are important and pay extreme attention to Inner Diameter and Outer Diameter when purchasing the tubing to make sure they will all fit. My elbows I bought were 5/32 to something like 9/64 and the the tube would not stay in there which is important with a pressure sensitive system.

Keep this thread in mind when someone is asking about those small vacuum lines.
Reply
Old Jan 8, 2017 | 03:44 PM
  #8  
Outlaw Star's Avatar
CF ADMIN
Veteran: Army
 
Joined: Sep 2010
Posts: 34,088
Likes: 257
From: Lantana, Fl
Year: 1996
Model: Cherokee (XJ)
Engine: 4.Slow
Default

You will be fine with making your own. Just use quality line so it does not collapse under vacuum.
Reply
Old Jan 9, 2017 | 05:04 PM
  #9  
cruiser54's Avatar
::CF Moderator::
 
Joined: Aug 2011
Posts: 43,971
Likes: 1,578
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Default

Thanks for the update!!
Reply

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 



All times are GMT -5. The time now is 01:51 PM.