4.0 Engine sputtering/losing power - 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 > TJ Wrangler Technical Forum > 4.0 Engine sputtering/losing power

TeraFlex Now at Rockridge 4WD! BEST DEALS around!Alloy usa heavy duty ball joint kitsENGO QUADLUX 6" to 54" LED AMBER AND WHITE MULTI

Reply
Unread 12-23-2011, 11:10 PM   #1
beserkur
Registered User
2001 TJ Wrangler 
 
Join Date: Feb 2010
Location: Montreal, Quebec
Posts: 98
4.0 Engine sputtering/losing power

hello everyone,
This has happened twice so far,today and yesterday,
Leave for work in the morning,little traffic so no idling.Leave work,stuck in traffic for at least 15 mins,then suddenly engine is pinging,shuddering,no power(500 to 1100 rpms max)Turned off engine,restarted it right away-everything's fine,drove home ok.
This morning,same as yesterday,left work,caught 20mins traffic(bumper to bumper)was almost home (was driving at 100km)same symptoms,again,pull off to the side,turn motor off,restarted,ran fine as if nothing happened.

So,the second time when I pulled off to the side,I tried a few things to see if I could diagnose this-I floored it to see if my rpms would go any higher,nope but the motor pings something fierce.Next i tried just letting off the gas completely to see if it would stall on it's own-nope,kept running rough but wouldn't stall-let it for at least 3 mins.
then I kept "goosing" it to see if I could get it to stall that way-no dice.

The first time it did it-I had fueled up that morning,at the same place I always do-but the station is not a banner type-just an independent.
I believe it's either bad gas or water in the gas.since it has never happened before it just reaffirms my belief.
Another interesting fact is that about 2 weeks ago my CEL has come on and stayed on ever since.I now believe that was an early indicator that the gas is poor quality or contaminated with water.
I'm gong to check more thoroughly tomorrow but I wanted to know if anyone has any ideas on this.

__________________
.[__]
OlllllllO
[]__[]

Jeep [COLOR="Red"]"Improvise,Overcome,Adapt"-Recon Motto[/COLOR]
beserkur is offline   Reply With Quote Quick reply to this message
Unread 12-23-2011, 11:54 PM   #2
HarryJeepGuy
Registered User
 
Join Date: Dec 2011
Posts: 50
What code is it throwing?!? If the light has been on for 2 weeks I doubt it's bad gas.
I'm assuming you don't know the key trick to get the CEL code. With the Jeep parked and off, turn the key from off to on 3 times fast without starting it, and leave it in the on position. It will display the code(s) where the odometer is.
HarryJeepGuy is offline   Reply With Quote Quick reply to this message
Unread 12-24-2011, 09:14 AM   #3
Cassafrass
Registered User
2000 WJ 
 
Join Date: Oct 2010
Location: Arizona
Posts: 624
I had basically the same problem with my 4.0. It happened twice within a few days. One time I pulled over, turned it off and it ran fine. The second time a few days later it happened, the CEL flashed, I pulled over, let it chill out (never turned it off) pulled back on the highway and it hasn't done it since. Mine was throwing a code for a cylinder misfire. Its been months since then. No CELs, no loss of power, nothing.
Cassafrass is offline   Reply With Quote Quick reply to this message
Unread 12-24-2011, 11:14 AM   #4
mightydog78
Registered User
2013 JK Wrangler 
 
Join Date: Jan 2009
Location: Charlotte/Winston-salem, NC
Posts: 1,989
Spark plugs, o2 sensor, catalytic converter, dirty intake, TPS, IAC
__________________
2013 JKU Sahara

Charlotte, NC / Southport, NC

Mechanical Engineer
mightydog78 is offline   Reply With Quote Quick reply to this message
Unread 12-24-2011, 02:05 PM   #5
JPNinPA
Registered User
2005 LJ Wrangler 
 
Join Date: Feb 2011
Location: Dayton, Ohio
Posts: 2,278
May just be bad gas like you think. Being it does it only while idling, I'd clean the TB and IAC. Did you note any temp issue or battery voltage issues?
__________________
"Never look down on anyone unless your helping them up"- Jesse Jackson
JPNinPA is offline   Reply With Quote Quick reply to this message
Unread 12-26-2011, 02:13 PM   #6
beserkur
Registered User
2001 TJ Wrangler 
 
Join Date: Feb 2010
Location: Montreal, Quebec
Posts: 98
Quote:
Originally Posted by HarryJeepGuy View Post
What code is it throwing?!? If the light has been on for 2 weeks I doubt it's bad gas.
I'm assuming you don't know the key trick to get the CEL code. With the Jeep parked and off, turn the key from off to on 3 times fast without starting it, and leave it in the on position. It will display the code(s) where the odometer is.
Hi Harry,well I do know how to get the codes,and there are several,but it's all related to misfiring and insufficient voltage etc....
But I still maintain it's bad gas.The crank and cam sensors are new.
I also gotta let you know that I am a mechanic,so I have a very good knowledge of what is going on,just wanted some input from you guys to see if I'm right.
It seems these crank and cam sensors fail quite often(twice in my case)
I;m going to drain my tank and put some fresh gas from a good known source and try it out.I'll get back to you guys and let you know what happens.
Just for fun I'll throw out the codes I've got....
P0353
P0352
P0351
P0301
P0302
P0303
P0304
P1391-this is crank/cam sensor codes.
__________________
.[__]
OlllllllO
[]__[]

Jeep [COLOR="Red"]"Improvise,Overcome,Adapt"-Recon Motto[/COLOR]
beserkur is offline   Reply With Quote Quick reply to this message
Unread 12-26-2011, 02:50 PM   #7
HarryJeepGuy
Registered User
 
Join Date: Dec 2011
Posts: 50
That's why I hate to assume... Lol. I don't know your year or milage, but if you have changed your cam and crank sensors twice already, 0351,0352,and0353 make we think your coil rail could be going bad. Not enough spark causing misfires.

P0351 (M) Ignition Coil # 1 Primary Circuit Peak primary circuit current not achieved with maximum dwell time.

P0352 (M) Ignition Coil # 2 Primary Circuit Peak primary circuit current not achieved with maximum dwell time.

P0353 (M) Ignition Coil # 3 Primary Circuit Peak primary circuit current not achieved with maximum dwell time.
HarryJeepGuy is offline   Reply With Quote Quick reply to this message
Unread 12-26-2011, 05:25 PM   #8
beserkur
Registered User
2001 TJ Wrangler 
 
Join Date: Feb 2010
Location: Montreal, Quebec
Posts: 98
Quote:
Originally Posted by HarryJeepGuy View Post
That's why I hate to assume... Lol. I don't know your year or milage, but if you have changed your cam and crank sensors twice already, 0351,0352,and0353 make we think your coil rail could be going bad. Not enough spark causing misfires.
well my odometer just hit the 100,00 kilometer mark(60,000 miles)
It would surprise me that the coil rail would fail at this early stage,but it is a possibility,just seems peculiar that it would be so intermittent and also that it runs just fine if I stop and restart.
Anybody have a coil rail fail that has the same symptoms as mine?
It seems to me that it would happen more and more as I drive it and be less intermittent.
I'm still sure that it was bad gas/water in gas-this would surely screw up the O2 sensor,causing my CEL to illuminate.I could care less about that idiot light since they malfunction all the time,meaning any little thing can cause it to come on,not necessarily affecting performance.
__________________
.[__]
OlllllllO
[]__[]

Jeep [COLOR="Red"]"Improvise,Overcome,Adapt"-Recon Motto[/COLOR]
beserkur is offline   Reply With Quote Quick reply to this message
Unread 12-26-2011, 06:00 PM   #9
JPNinPA
Registered User
2005 LJ Wrangler 
 
Join Date: Feb 2011
Location: Dayton, Ohio
Posts: 2,278
I haven't experienced those codes but what is your battery voltage? Also what about checking the ground to the engine and to the rail?
__________________
"Never look down on anyone unless your helping them up"- Jesse Jackson
JPNinPA is offline   Reply With Quote Quick reply to this message
Unread 12-26-2011, 08:05 PM   #10
HarryJeepGuy
Registered User
 
Join Date: Dec 2011
Posts: 50
I'm surprised you had to change your cam and crank sensors twice already at 60k miles. I changed my coil rail at 100k troubleshooting a misfire code. It ended up being a fuel injector, but I left the new rail on and kept the old one for a spare. I've had a tank of bad gas before, and it ran like **** the entire time, backfiring and stalling. I guess you have plenty of things to look at, good luck. I'd try resetting the codes to see what it throws next. If it's been 2 weeks you're on a different tank of gas by now right?
HarryJeepGuy is offline   Reply With Quote Quick reply to this message
Unread 12-26-2011, 08:43 PM   #11
JPNinPA
Registered User
2005 LJ Wrangler 
 
Join Date: Feb 2011
Location: Dayton, Ohio
Posts: 2,278
http://www.jeepforum.com/forum/f13/h...351-x2-704058/

Was interested being I never experienced this myself. Here is a link to help you out.
__________________
"Never look down on anyone unless your helping them up"- Jesse Jackson
JPNinPA is offline   Reply With Quote Quick reply to this message
Unread 12-28-2011, 12:19 PM   #12
beserkur
Registered User
2001 TJ Wrangler 
 
Join Date: Feb 2010
Location: Montreal, Quebec
Posts: 98
Quote:
Originally Posted by JPNinPA View Post
I haven't experienced those codes but what is your battery voltage? Also what about checking the ground to the engine and to the rail?
Battery is 2 months old and battery load test gives me 12.4v and a 15 sec load drops it to 11.6-then right back up to 12.4.
The grounds are all good.
__________________
.[__]
OlllllllO
[]__[]

Jeep [COLOR="Red"]"Improvise,Overcome,Adapt"-Recon Motto[/COLOR]
beserkur is offline   Reply With Quote Quick reply to this message
Unread 12-28-2011, 12:26 PM   #13
beserkur
Registered User
2001 TJ Wrangler 
 
Join Date: Feb 2010
Location: Montreal, Quebec
Posts: 98
Quote:
Originally Posted by HarryJeepGuy View Post
I'm surprised you had to change your cam and crank sensors twice already at 60k miles. I changed my coil rail at 100k troubleshooting a misfire code. It ended up being a fuel injector, but I left the new rail on and kept the old one for a spare. I've had a tank of bad gas before, and it ran like **** the entire time, backfiring and stalling. I guess you have plenty of things to look at, good luck. I'd try resetting the codes to see what it throws next. If it's been 2 weeks you're on a different tank of gas by now right?
Yeah I was really surprised too,it just decided not to start one morning,no forewarning at all. about year apart I'd say.

But anyways,I went out for a test drive yesterday,after about 30 mins driving time-no traffic,it started doing it again,put it in neutral and turned off engine,restarted and it was fine.still 1/2 tank left of that same gas.
I think I'll just run it dry,then fill up.
__________________
.[__]
OlllllllO
[]__[]

Jeep [COLOR="Red"]"Improvise,Overcome,Adapt"-Recon Motto[/COLOR]
beserkur is offline   Reply With Quote Quick reply to this message
Unread 12-28-2011, 04:47 PM   #14
JPNinPA
Registered User
2005 LJ Wrangler 
 
Join Date: Feb 2011
Location: Dayton, Ohio
Posts: 2,278
If the gas doesn't correct it look at the link I posted up. Skip to the end and see they bought the CPS from the dealer. The others didn't fix the issue or failed quickly.
__________________
"Never look down on anyone unless your helping them up"- Jesse Jackson
JPNinPA is offline   Reply With Quote Quick reply to this message
Unread 01-17-2012, 08:17 PM   #15
beserkur
Registered User
2001 TJ Wrangler 
 
Join Date: Feb 2010
Location: Montreal, Quebec
Posts: 98
UPDATE: Replaced the crank sensor-all is well,problem solved.
__________________
.[__]
OlllllllO
[]__[]

Jeep [COLOR="Red"]"Improvise,Overcome,Adapt"-Recon Motto[/COLOR]
beserkur 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.