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Topic Review (Newest First)
02-23-2013 12:19 PM
xpdude sorry some how i posted here instead of a new thread. my bad....
02-23-2013 12:18 PM
xpdude
1995 wrangler yj engine problem trying to fix and go jeeping!

The problem is that it sounds like the timing is out on it when i turn it on. it will run ok and miss a little run semi smooth. i rev it and the engine light comes on and it stalls. restart, then it loads up and it start to flood with gas then backfires loudly 3-4 times sounds like a john deere 60 tractor when you gas it, then it will quit. try to restart and it vaporlocks unless i take out the f/p relay, then it starts then dies and backfires. 2.5 liter auto trans 95 wrangler is what i am serviceing. i know it has good fuel presure, new fuel pump, 35PSI then 40 psi when you remove the vacumm to the fuel regulator with the few mins i had it running i checked the fuel presure. spark is ok also. compression is 150psi 1-3 cyl then 160psi on the 4th cyl. I have replaced the timing chain, timed it according to the haynes manual. distributor was installed according to the haynes manual, 10 o clock on the oil pump gear and putting that pin to keep the rotor still. The entire ignition system has been gone through... all the sensors related to the ignition system, crank positon sensor, coil pickup, COIL its self, and cap/rotor / spark plugs have been replaced. I am wondering what the heck is wrong with my jeep that it won;t run! check engine light comes on then goes off when you get it started. i haven't pulled codes yet.
10-03-2011 11:42 PM
benaldridgejr
Quote:
Originally Posted by hep49
How much vacumn at the motor that is on the front axel?
Mine seems to have very little.
It should be enough to almost keep yur finger sucked on the hoses. It doesnt take much if yur actuator is in good working order.
09-23-2011 08:10 PM
hep49 How much vacumn at the motor that is on the front axel?
Mine seems to have very little.
08-10-2011 10:26 PM
asia517
Quote:
Originally Posted by jakec View Post
i took all the vacuum lines off and flipped the shift fork housing upside down, bolted it back on and now its locked all the time like a tj. it works great. the front diff spins all the time but it doesnt affect anything unless there is another problem or you have a fulltime locker in front.
I'm wanting to take all these spaghetti lines out and simplify the vacuum lines and wiring as much as possible, is there anyway you can elaborate on this post you wrote, which hoses did you remove? any pics or info would be a huge help. thanks Erik

I will pm you my contact info maybe it would be easier to have a 5 min conversation on this.

Thanks again
08-08-2011 09:57 PM
Beastmaster Wow, sorry to hear that. People have no idea all the training and experiance going to waste. Thank you for you service and I hope all goes well.
08-08-2011 07:01 AM
army2000ng That's o.k. I first served in the Airforce before transferring to the Army. I did 21 years before retiring. I am a disabled vet without a job, it seems being disabled and a little older hinders my ability to get a job. People consider me a risk. Oh well; guess I'll spend more time with my jeep. Gonna have it painted today? "Green."
08-07-2011 02:48 PM
Beastmaster Out frickin' standing Army!!! I think this is exactly what I am looking for. I promise to not say bad things about our boys in green (I'm retired AF btw). Now I just need to figure out what goes to the controls. ;-)

Thank you very much for the help and advice.
08-07-2011 08:24 AM
army2000ng
hvac-heating-air diagram for 1990 jeep

Beastmaster:
Hope this diagram helps.
08-07-2011 08:20 AM
army2000ng You might want to invest in two books. M.R.279 volume 1 and 2. They are about 70 bucks or less on e-bay. These books are specifically for Jeep Wrangler YJ. They were made from the auto manufacturer to the jeep mechanic.It's a little pricey but if you are gonna keep your jeep for a long time having the right manual will go a long way. The Chilton auto manual and others show way to many other models, where this book is just for those models needed to fix or repair your jeep by year, engine size and transmission. I too have an after market carb, Holly 2bbl.
08-06-2011 07:16 AM
Beastmaster Thanks for the diagram. I think I can use it but what I am actually looking for is some information on the hoses behind the dash board (going from the heater/AC control box to the various homponents of the hea/AC system, those are the ones I am missing. The engine vacuum diagram you posted will help too, so thanks. BTW, to answer your question, my air cleaner is round, on top. I have an after market Holley 2bbl TBI system as well as an after market distributor.
08-05-2011 05:35 AM
army2000ng Is you air cleaner on the side or on top(round ) like mine? This is for a 2.58 cu in 4.2
08-05-2011 05:32 AM
army2000ng
BeatMaster Vacuum Diagram

Here is an attachment for the Jeep Vaccum line diagram
08-05-2011 05:27 AM
army2000ng
Quote:
Originally Posted by Beastmaster View Post
Thanks for the post Army, my YJ has a 6 cyl with lots of after market work. I don't know why the previous owner pulled out the lines but as long as I can find out the routing I think I can replace them and get things (heater, etc.) running.
"I am sending you a picture of the vacuum diagram. Hope it's clear enough for you, make sure you print it out."
08-04-2011 08:39 PM
Beastmaster Thanks for the post Army, my YJ has a 6 cyl with lots of after market work. I don't know why the previous owner pulled out the lines but as long as I can find out the routing I think I can replace them and get things (heater, etc.) running.
08-04-2011 08:24 AM
army2000ng
Quote:
Originally Posted by army2000ng View Post
What would anyone consider to be a good price to re-attach the vacuum lines, replace front main gasket and valve cover gasket? Anyone please answer.
Well after spending good money, all my vacuum lines are finally installed correctly. Found one mechanic out of 7 that knew how to work on them.
08-04-2011 08:22 AM
army2000ng
1988 Jeep yj

Is you 1990 a 4 or 6 cylinder? What engine does it have?
08-03-2011 08:23 PM
Beastmaster Hi all, I'm new to the forum and have a vacuum related question. I just bought a 1990 YJ, great vehicle, but when I went to troubleshoot the heater controls I found out the previous owner stripped all vacuum lines out from behind the dash. Does anyone have a diagram of how the heater (and A/C) control vacuum hoses are supposed to be routed? Thanks in advance.
08-02-2011 04:24 PM
army2000ng What would anyone consider to be a good price to re-attach the vacuum lines, replace front main gasket and valve cover gasket? Anyone please answer.
02-20-2011 08:46 PM
benaldridgejr
Quote:
Originally Posted by Jdean14
I replaced the 4WD Actuator. It worked once and shifted the Jeep into 4WH after a short turn of the wheel and a quick roll forward. It was working great. Then I backed the rear wheels into some snow and tried to use the front wheels to pull out. After a loud pop, the front wheels stopped working and rear wheels were spinning. The front wheels would not engage any more even after several tries. When I shift into 4WD there is a slight metal clicking noise like the front wheels are just missing engagement. Is there something I might have done wrong that is making the fork not slide all the way or anything else that would cause the system to slip out.
I would think you still have a vacuum problem. See how strog your vacuum is with the two lines off by shiftin in and out of 4wd. Also, if those C clips arent in perfect they can pop off causing the fork to not engage properly. Start by taking the actuator back off and check your clips on the fork.
02-20-2011 08:41 PM
benaldridgejr Great post! I recently just had to do a vacuum diagnosis on mine also. Turned out to be the fork actuator. (the disc shaped object on your front diff that the vacuum lines go to) another quick 4x4 diag is to pull the two lines off and feel for a vacuum, switch to 4wd and see if the vacuum changes to the other hose. If so, you probly need an actuator. If it doesnt change, the vacuum switch on the diff is bad or there is a leak. There are also plastic lines under the battery that crack the most often due to old batteries corroding and such.. Just get all the old wire loom off them and do some spraying. Be sure to re-loom them after tho. I LOVE the posi-lock system but last i checked it was pricey.. But fail proof! Hope this helps some too.
02-20-2011 08:24 PM
yuanyelss was wondering what the effects of this will be? One was completely torn off right at the plug in point, and the other had a very small, threadlike, piece of wire still holding it in place until I bumped it and it completely snapped off.
02-19-2011 12:56 PM
J0J0 wow this is well wrote thanks alot i am thinking i am having the same problems its not going into 4wheel all the way, the tire spins then kinda stops hope this is my problem i don't know what else it could be.
02-04-2011 12:50 PM
Jdean14 I replaced the 4WD Actuator. It worked once and shifted the Jeep into 4WH after a short turn of the wheel and a quick roll forward. It was working great. Then I backed the rear wheels into some snow and tried to use the front wheels to pull out. After a loud pop, the front wheels stopped working and rear wheels were spinning. The front wheels would not engage any more even after several tries. When I shift into 4WD there is a slight metal clicking noise like the front wheels are just missing engagement. Is there something I might have done wrong that is making the fork not slide all the way or anything else that would cause the system to slip out.
02-04-2011 10:22 AM
WranglerYJ91 Google 4x4 posi-loc
02-01-2011 06:22 PM
T. Dixon I have a 91 YJ. Went through all the vac. check lists with flying colors. I pulled the actuator and watched it shift outside of the axle ok. If I manually slide the unit into 4X4 and put the actuator back it works untill I disengage it and try to reingage it, then no luck. My shift fork has about 3/8" of play between the fork and the shaft. Possibly this play won't let the actuator push the slide into 4X4? I ordered a fork from Quadratec to try a new one. Any suggestions would be appreciated.
01-12-2011 09:15 PM
jakec i took all the vacuum lines off and flipped the shift fork housing upside down, bolted it back on and now its locked all the time like a tj. it works great. the front diff spins all the time but it doesnt affect anything unless there is another problem or you have a fulltime locker in front.
12-21-2010 10:47 AM
Seaules where did you get the posi kit??
12-15-2010 12:53 AM
GavinDubai Stupid question.. what does the vacuum do? Where is it located?
12-08-2010 11:59 AM
gracemely Good information. Well written too.
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