1995 Jeep Wrangler runs rough won't idle - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > YJ Wrangler Technical Forum > 1995 Jeep Wrangler runs rough won't idle

FS: 2007-2013 Jeep Wrangler "HALO" Angel Eye KitFlowmaster's Force II Axle-back exhaust system for the 201FS: Wranger BRIGHT License Plate LED! Just $3! Great value

Reply
Unread 04-18-2010, 09:24 PM   #1
serge110
Registered User
1995 YJ Wrangler 
 
Join Date: Apr 2010
Location: colorado
Posts: 7
1995 Jeep Wrangler runs rough won't idle

I gave it a basic tune-up to include: Plugs, wires, filters, cap, rotor. Replaced the O2 sensor, fuel filter and the fuel pressure regulator. None of this has helped. It still will not idle unless my foot is on the gas. Any input would be great as I feel like I am stumped at this point.

serge110 is offline   Reply With Quote
Unread 04-18-2010, 10:07 PM   #2
Straycur
Registered User
1995 YJ Wrangler 
 
Join Date: Jan 2009
Location: AK
Posts: 93
Are you getting a CEL? Sounds like a Throttle Position Sensor
Straycur is offline   Reply With Quote
Unread 04-19-2010, 12:33 AM   #3
serge110
Registered User
1995 YJ Wrangler 
 
Join Date: Apr 2010
Location: colorado
Posts: 7
What is the CEL?
serge110 is offline   Reply With Quote
Unread 04-19-2010, 01:07 AM   #4
Larry93
Registered User
1993 YJ Wrangler 
 
Join Date: Jun 2004
Location: long island
Posts: 333
Check engine light.
Larry93 is offline   Reply With Quote
Unread 04-19-2010, 06:24 AM   #5
serge110
Registered User
1995 YJ Wrangler 
 
Join Date: Apr 2010
Location: colorado
Posts: 7
Check Engine Light

The check engine light is not on? I think it should be, possibly doesn't work. We just purchased this weekend for our son. Thoughts?
serge110 is offline   Reply With Quote
Unread 04-19-2010, 07:21 AM   #6
Roadyy
Registered User
 
Roadyy's Avatar
1994 YJ Wrangler 
 
Join Date: Mar 2010
Location: Down South
Posts: 1,592
does the cel come on when you turn the key on before cranking it?
if it does then turn the key on-off 5 times really quick then leave in on position for couple seconds it will start blinking. you will get several sets of blink sequences. example. blink blink pause blink =21 blink blink blink pause blink blink blink = 33 etc. Then compare those to the codes to see what errors you have. you can use the search feature to find the thread for the codes or look in your Haynes repair book.
Roadyy is offline   Reply With Quote
Unread 04-19-2010, 08:12 AM   #7
gkainz
Registered User
1995 YJ Wrangler 
 
Join Date: Nov 2005
Location: Arvada, CO
Posts: 263
IIRC, it only takes 3 off-on cycles of the key to start the code blink sequence?
gkainz is offline   Reply With Quote
Unread 04-19-2010, 10:28 AM   #8
serge110
Registered User
1995 YJ Wrangler 
 
Join Date: Apr 2010
Location: colorado
Posts: 7
Great - the codes I got were 12 (battery disconnected/all is normal - did disconnect the battery yesterday for testing) 33 (air conditioning relay -which we don't have air) and 55 for end of codes.

When I did the fuel pressure test it was at 38 1/2 and when I removed the vacuum hose it went to 39. So, I replaced the fuel pressure regulator and nothing changed.

Could it be a map sensor? Going to start looking for more vacuum leaks, possibly change out the manifold gasket....thoughts
serge110 is offline   Reply With Quote
Unread 04-19-2010, 10:48 AM   #9
YJake
Registered User
1991 YJ Wrangler 
 
Join Date: Jun 2008
Location: Orlando, FL
Posts: 2,199
I would almost say it's the Throttle Position Sensor (TPS), but I can't physically hear or feel what's going on.

Does it sound funny while it's running like it's misfiring?

Jake
__________________
/l , [____],
l---L--[]lllllll[]-_
()_) ()_)==@=)_)

Quote:
Originally Posted by clemsonfan16 View Post
The 4banger only whines because it wants more!
Quote:
Originally Posted by Opihi59 View Post
3 Things to know about the forum: Always PB blaster, Always check the FAQ, Always do a search, and if none of that works, ask Mean Max.
YJake is offline   Reply With Quote
Unread 04-19-2010, 11:02 AM   #10
serge110
Registered User
1995 YJ Wrangler 
 
Join Date: Apr 2010
Location: colorado
Posts: 7
Yes it does sound and feel like it is misfiring. Give me a dwell meter timing light and a carb.
serge110 is offline   Reply With Quote
Unread 04-19-2010, 12:30 PM   #11
Que89YJ
Web Wheeler
1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit, Michigan
Posts: 14,549
No CEL light and its running rough could be a few different things. It sounds like you've turned a wrench so start with the vacuum leak check. Take a can of starter fluid or carb cleaner and spray around the engine looking for a change of idle for a vacuum leak. While you are at it, clean the throttle body really good too. Is it any different at idle cold and warm? The next step would be the temp sensor. There are 2 of them; one for the guage and one for the Engine controller.You want to check/replace the one for the engine controller. It is in the front of the block by the thermostat housing. Check/replace the TPS sensor. BTW the idle pressure should be 31PSI on the fuel pump. With a new regulator I dont know how it is reading high with the vacuum hose on and off. The fuel pressure should increase as vacuum increases.
Que89YJ is offline   Reply With Quote
Unread 04-19-2010, 09:33 PM   #12
Straycur
Registered User
1995 YJ Wrangler 
 
Join Date: Jan 2009
Location: AK
Posts: 93
To check the TPS, you need a multimeter. The center wire on the harness is the TPS output. If you backprobe this with the key on, these are the readings you should get - idle more than 200 milllivolts, WOT less than 4.8 volts.
If you actuate the throttle plate, the TPS should follow smoothly.
It may also help to pull your idle air control motor next to the TPS and clean the pintle with a soft cloth and some alcohol, and check the bore for blockage.
Straycur is offline   Reply With Quote
Unread 05-02-2010, 08:35 PM   #13
serge110
Registered User
1995 YJ Wrangler 
 
Join Date: Apr 2010
Location: colorado
Posts: 7
Thank you all for your help! After combining all of the above with several more things the Jeep is up and running!!! Thank you so much for your help!
serge110 is offline   Reply With Quote
Unread 05-02-2010, 08:42 PM   #14
YJake
Registered User
1991 YJ Wrangler 
 
Join Date: Jun 2008
Location: Orlando, FL
Posts: 2,199
What did the problem end up being?

Jake
__________________
/l , [____],
l---L--[]lllllll[]-_
()_) ()_)==@=)_)

Quote:
Originally Posted by clemsonfan16 View Post
The 4banger only whines because it wants more!
Quote:
Originally Posted by Opihi59 View Post
3 Things to know about the forum: Always PB blaster, Always check the FAQ, Always do a search, and if none of that works, ask Mean Max.
YJake is offline   Reply With Quote
Unread 05-03-2010, 06:27 AM   #15
sloan74
Registered User
2013 JK Wrangler 
 
Join Date: Apr 2010
Location: Charlotte NC
Posts: 605
Might want to do the fluid change also before you give it to him, esp if he is going to take it offroad. 9 times out of 10 this has not been done in a while. I just did mine this weekend on a 95' I purchased as well.

You need to (I am assuming it's a 2.5L 5 speed manual):

1.) Transmission fluid change (very easy, 15/16 socket head, takes 80w90 gear oil - use synthetic, fill until it's full - almost dripping out the fill plug)

2.) Transfer Case fluid change (very easy just need a 30mm socket head, uses ATF +4, use good stuff, you only need 1.25 quarts)

3.) Rear differential fluid change + new gasket ($3.50 at Autozone), uses 1/2 socket head, this one might take a few to change out depending on the last time it was done, you will need to clean the cover real good and casing ring itself before you reseal it, rebolt and refill. Most my time spent here for me was cleaning the cover/casing, mine was in aweful shape.... Uses 80w90 gear oil - use synthetic, fill until it's full - almost dripping out the fill plug

4) Front differential fluid change + new gasket (same as the rear for the most part), although this one is a little easier to do.

All 4 of these are relative easy though. If you can do all the stuff you already listed, these should not be a problem.

Estimating $70-100 (pending on brand/quality) bucks total for the gaskets + fluids for all 4.

Last edited by sloan74; 05-03-2010 at 06:48 AM..
sloan74 is offline   Reply With Quote
Reply
Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.