miss at 2500 rpm - 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 > miss at 2500 rpm

ROCK BOTTOM prices on LIFT KITS at Rockridge4wd!! WANT TO Alloy usa heavy duty ball joint kitsWe have FLASHLIGHTS! Great for your Emergency bag!

Reply
Unread 04-28-2007, 09:55 PM   #1
greenyiride
Registered User
 
Join Date: Sep 2005
Location: San Diego
Posts: 26
miss at 2500 rpm

Well I got a solid week of normal operation after my tranny rebuild and new clutch.

A new problem now, my Jeep (1995 2.5 stick) has a miss at 2500 rpm and a whirring sound is coming from the engine compartment at speeds over 35 mpd but only when I feather the gas. If I'm off the gas it stops and if I'm on the gas it stops it only happens between those times and only while driving. The noise started before the misfire problem. I can't get it to miss revving it in the driveway, it only happens while driving. It sounds great at other rpm. I did a search and found a thread about a bad TPS but I had replaced mine about 3,000 miles ago. I have checked the plugs, wires and cap and I have a fairly new coil.

The whirring noise is similar to the noise the exhaust makes when the cat is broken- up. Before you ask I just replaced the cat and cleaned the old remnants out of the exhaust. I get no codes from the computer.

I know others have experienced the "hard to diagnose problems" that Chrysler has so graciously provided us. I guess it gives me something to do other then drive the Jeep, keeps the miles low.

greenyiride is offline   Reply With Quote Quick reply to this message
Unread 04-28-2007, 11:34 PM   #2
Coolhand1
Registered User
 
Join Date: Apr 2007
Location: East Central Oklahoma
Posts: 75
I feel your pain, I'm having similar "hard to diagnose Chrysler problems"
__________________
[B]1991 Wrangler Renagade[/B]
31x10.50 TRXUS M/T
Hurc-lined
Centerlines
Airaid
For the record, 3,692 Renegades were built in 1991.
Coolhand1 is offline   Reply With Quote Quick reply to this message
Unread 04-29-2007, 12:43 PM   #3
Jamezcon
Registered User
1995 YJ Wrangler 
 
Join Date: Feb 2006
Location: westport, Ct
Posts: 70
Fuel Pump!!!
Jamezcon is offline   Reply With Quote Quick reply to this message
Unread 04-29-2007, 12:46 PM   #4
Jamezcon
Registered User
1995 YJ Wrangler 
 
Join Date: Feb 2006
Location: westport, Ct
Posts: 70
my 2.5 was doing the same
Ended up being the Fuel Pump
Now runs like a charm
Jamezcon is offline   Reply With Quote Quick reply to this message
Unread 04-29-2007, 01:08 PM   #5
greenyiride
Registered User
 
Join Date: Sep 2005
Location: San Diego
Posts: 26
Got new fuel pump and filter a little while ago while trying to figure out an intermitent no start / engine shut off problem. The pump was weak. I reset the computer last night, I'll try driving it again and see if it changes. I'm thinking maybe a vacume leak?

When I figure it out I'll post the answer as I'm sure it is happening or will happen to others. I'm just trying to avoid going to the dealer and getting into the, "lets change this part and see", cycle.
greenyiride is offline   Reply With Quote Quick reply to this message
Unread 04-29-2007, 04:51 PM   #6
flame0086
Registered User
1991 YJ Wrangler 
 
Join Date: Nov 2005
Location: Bellingham, WA
Posts: 1,587
I once had a random miss, with some bucking of the jeep. It turned out to be a bad TPS. You would know if it was something pluged in the exhaust because you would lose a noticiable power loss.

I would start with checking some of the basics. Make sure all your ignition wires a solidly pluged in. Also pop off the distributor and make sure all of the contacts are clean and not corroded.

Since it only happens at a cretain RPM, I would suspect a bad sensor of some sort. If not the TPS, maybe the MAP?
__________________
100 mpg!! Western Washington Univeristy X-Prize Team http://wwuxprize.blogspot.com/

Support Search and Rescue
Get Lost
flame0086 is offline   Reply With Quote Quick reply to this message
Unread 05-04-2007, 12:38 AM   #7
greenyiride
Registered User
 
Join Date: Sep 2005
Location: San Diego
Posts: 26
It turned out to be the MAT sensor, it ended up showing a check engine light after a couple days (code 23, MAT sensor). I pulled the sensor from the intake and found it was crusted with debris. I cleaned it with carb cleaner, put it back in and my mysterious miss at 2500 rpm is gone. I will be replacing it with a new one soon. I hope this helps someone.
greenyiride is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


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.