Starting issue

[offroadohio]

I have developed a starting issue on my 07 with 38,000 miles. It only seems to do it when the engine has been working harder, i.e. towing a trailer, offroading ect..

With the turn of the key it will start up, run a couple seconds and die. Sometimes it will start right back up with no issues, other times I have to hold the pedal to the floor until it it starts up and then quickly let off the pedal to keep it running.

There is no CEL, and I ran a diag on it just to check the memory and the only thing I got was a code for the electric fan ( I had an issue with it not kicking on)

It just recently started doing this. I've had one time that I had to let it sit in the middle of the woods for 10 minutes before it would fire back up.


Anyone have any idea's?

 

[offrovering]

have you had the battery checked? shouldnt be bad but I would start ruling that out. if the alternator is bad and not charging the battery, it could be drained. if the alt is bad usually you will have a wild tach.

no other codes or symptoms? low idle before it dies, etc?

 

[incommando]

Are you using a good name brand gas? My brother had this issue with a 4.7 in a Dakota and they recommended he use a better gas. He did & it has not happened again. Just a thought.

 

[offroadohio]

Its not a battery or alternator issue. It cranks and starts fine.

When it does it, after I get it started it only idles at around 350rpm... normally its around 700 I think.

Only does it when engine is worked harder than your typical sunday drive.

It did it worst at Jeepskool than anywhere else and I was running BP fuel.

It id dit once today runnin mom n pop starfire fuel.

 

[Ry' N Jen]

Loose ground somewhere?
Ours had, then I checked the battery again and even though it put out good power levels, it had an oddly loose negative terminal which ended being the problem.

 

[chirokj]

had a similar issue on the fiance's escape but it only happened after it rained. the battery cables were fine, used shell gas so i played around with the RPM screw under the hood and brought them up a bit. it would idle at 400ish before but now is fine

 

[offrovering]

ok so you have low idle. cleaned tps, or maf/map? not getting enough air causing low idle and possible stall.

pulled any vac lines at the throttle body to see if its a vac leak?

 

[J-Thompson]

offroadohio
you said that you had an issue with the fan not kicking on
you also said that it only does it when it has been "working hard"
I had just about the same problem with my TJ
I had to do a bunch of cooling system up grades to get it to stop
I added
electric pusher fan
aux trans cooler
new fan shroud ,old one got broke by a branch a while back
new fan clutch
now I can run trails in the 95* heat of the summer with the AC on pushing the Jeep to the max with a 4.0 I6 that is not known for its cooling abilities with no issues

All that being said I would start looking for a very slight lack of cooling power
one thing to do would be to push it hard and then when you kill the engine just turn the key on and look at what the temp is
if it shoots all the way to the max or close there to it then that is your problem
hot engines do not like to start

 

[JeepJeepster]

When you said 'working hard,' define what you were doing with the jeep just before that. What do you tow and how heavy is it? Going offroad isnt really ******* the engine at all, I just put it in 4low and crawl around. I guess if you fly around in mud all day then yes, its harder on everything(very hard).

You said you had trouble with the fan not kicking on. What did you do to fix it and how did you figure out it wasnt kicking on? Did it ever over heat?

Have you tried to clean the TB or intake? A jeep with 38k shouldnt need to be cleaned all that much but you never know.

Get that code cleared and see if anymore some back.

 

[offroadohio]

It never gets above 1/2 on the temp gauge unless the fan doesnt kick on. regardless of how hard I run it. I THINK i fixed the fan issue by simply cleaning the connecotr, I'll find out as I am going on a trail ride tommorrow.
Fan usualy stops working any time I get any type of water in the engine bay. ( even car washes if I spray the bay down)

When I say hard I mean hard. 75mph towing a t trailer wieghing in at 3500+
5-6,000 rpm up muddy hills, rocks, etc.
http://www.youtube.com/watch?v=gCycdKLN_fY
Granted that video is of my old tubed out tracker, I do the same kind of lead footed driving in the liberty.


The easiest I have been on it when the starting issue has occured I was I towing my atv and little 400pound trailer. I shut it off to unload the quad the the shop and it took a few minutes to get it fired up.

The Jeep only idles low when it has this starting problem. With normal start up it idles where it should. When it has the issue, once I get it started it addles below 500rpm for a few minutes and then jumps abck to normal.

It has been VERY hot once. It was my fualt becuase I was running a/c on the trail, and had it stuck and was cranking 5,000rpm for a few minutes and then the computer shut it down. I never onc elooked at the guage. I normally watch my guages pretty well, but I'm typically in a 20+ year old vehicle that has issues already.
It had to cool down to normal temp before it would start back up.

It was a few months later that this current issue developed so I dont believe its related. However since then I keep an eye on the temp when offroading. Anytime it gets past 1/2 way I get out and check the fan. Everytime I've found it above 1/2way I've tapped the fan with a small hammer I now carry and its kicks on and drops back to the 1/2way mark. But like I said early I think I fixed the fna issue.

I just filled up with 92 octane BP gas and will be taking it out on the trails tommorrow. I will see if the problem pursist, or if it is indeed a crappy fuel related issue.

 

[J-Thompson]

Going offroad isnt really ******* the engine at all, I just put it in 4low and crawl around. I guess if you fly around in mud all day then yes, its harder on everything(very hard).

bro you must not be climbing any hills then
I am talking steep to the point that wheel spin is going to happen no matter what tires you have
so steep that you can not walk up them
steep that if it is wet you will not make it
so 4 low is not going to be enough to make it up your engine will be working
also on top of all this I am a huge sissy and need my AC going when it is above 85* out side

 

[offroadohio]

Took it out, had a fan issue early into the ride. got it to kick on and put a constant water supply froma garden hose for about 10mintues to the fan motor and it kicked on everytime. I'll be going to mechanical fan shortly.


As far as the starting issue it only occured a couple times today, and that was near the end of the day after I clogged the radiator fins with mud and it was running about 3/4 of the way up the guage. But this time it wou;d start, sputter a little and die, and then fire up and be fine without stepping on the throttle.

As my early post from yesterday stated I filled up with 93 octane instead of 87 octane, and put shell gasoline in instead of BP. I'm going to switch back to BP for the next ride and see what happens. Its very possible Incommando's "poor fuel quality" suggestion was the issue.

 

[tjkj2002]

I'll be going to mechanical fan shortly.

You will need to keep the electric fan,the mechanical fan for the KJ is NOT ment to be the sole cooling fan and you will still overheat.You must retain the electric fan,your check engine light will turn on without the electric fan connected also.

The HD cooling(new electric fan,shroud,mechanical fan,and clutch) kits are pretty cheap now,I just installed one yesterday and the guy bought it for under $250 shipped and took all of 10min to install.

 

[J-Thompson]

Took it out, had a fan issue early into the ride. got it to kick on and put a constant water supply froma garden hose for about 10mintues to the fan motor and it kicked on everytime. I'll be going to mechanical fan shortly.


As far as the starting issue it only occured a couple times today, and that was near the end of the day after I clogged the radiator fins with mud and it was running about 3/4 of the way up the guage. But this time it wou;d start, sputter a little and die, and then fire up and be fine without stepping on the throttle.

As my early post from yesterday stated I filled up with 93 octane instead of 87 octane, and put shell gasoline in instead of BP. I'm going to switch back to BP for the next ride and see what happens. Its very possible Incommando's "poor fuel quality" suggestion was the issue.

you have a cooling problem not a fuel problem
and you need to address it before you damage your engine
if you read my earlier post I had the same problem and I can now run
in 95* heat with the AC on working the piss out of my engine and never get above normal
if ANY THING makes your gauge get above normal temp then you have a cooling problem
address the cooling issue and the poor engine running will go away
or keep farting around with the fuel system and screw up your engine

I would fix the electric fan ,they will blow more CFM at idle than a mechanical fan
and CLEAN OUT THE RADIATOR AND CONDENSOR
if they have mud in them they are cutting air flow and making it harder for the radiator to cool the water
after this STAY OUT OF THE MUD

 

[offrovering]

not to switch things but 93 octane from shell is not poor fuel, if anything the BP is poor. your engine will not shut off from higher octane fuel

 

[offroadohio]

not to switch things but 93 octane from shell is not poor fuel, if anything the BP is poor. your engine will not shut off from higher octane fuel

Yeah, thats what I just said. I switched from BP to shell and went with high octane to see what it would do.

I clean the radiator after every outing. I pull the grille and the fan and wash it from both sides. If I want to stay out of the mud I will have to move from Ohio, it is impossible to go wheeling and not get into some mud somewhere.

I'm going to ad the mechanical fan and replace the current elec one with an aftermarket unit, also going to completely remove the radiator and wash it out along with the ac condensor, trans cooler and ps cooler.

As I also said I am going to switch it back to regular unlead and see if that effects anything, it may have just been a coinicidence ( sp???) that it started with very little issue every time yesterday even while hot