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-   -   Hey Guys I could really use your help. (http://www.jeepforum.com/forum/f28/hey-guys-i-could-really-use-your-help-2286929/)

JeepOwner33 04-02-2014 06:29 PM

Hey Guys I could really use your help.
 
I have been having an issue with my 2003 Jeep Liberty Renegade for about a year now. This issue has stumped 2 different repair shops and a jeep dealership. Maybe you guys have heard of this before and give me a little advice.

So the issue is this. The Jeep runs fine. Starts easily at the turn of the key. Perfect. Until the engine gets warm. If you drive about 4 or so miles and the engine gets warmed up, the next time you turn the engine completely off it will refuse to start for about half an hour.

It turns over just fine and cranks... and cranks... it just will not kick on. I am guessing it's either a heat or fuel line issue. If I leave the jeep sit for about 6 hours after driving it seems to be fine, but if I want to go somewhere immediately after its warms up, I have to wait half an hour. It's almost as if the jeep specifically waits half an hour after I first turn the key and it fails to start. It's amazingly frustrating.

I have replaced the fuel pump, the crankshaft sensor that was bad, and the fuel pump sensor and still have the issue.

Next I was going to try the spark plugs and wires and maybe even the coil packs to see if it does any good.

I have had the jeep at a couple of different good repair shops and even a jeep dealership shop and no one seemed to be able to chase down the issue.

I am sick to death of having to sit around and wait half an hour before I can go somewhere. I have been stranded like this about 10 times minimum. I am even considering a trade in, but I love my jeep. Please help!

tjkj2002 04-02-2014 07:33 PM

Any codes?

Since it's a heat issue suspect a cracked crank sensor or cam sensor,need to use a lab scope to check the square wave signals from both when it's not starting.Also did you replace the fuel filter when you did the pump? Talking about the one on top of the gas tank,it also has a pressure regulator in it.Since the KJ uses a returnless system that pressure regulator is very important.

JeepOwner33 04-02-2014 07:55 PM

Nope
 
No codes.

Replaced the crankshaft sensor that was tested as being bad, but that didn't fix the issue.

Cam sensor is one of my next options.

Fuel filter I do not believe so, I will keep that one in mind as well thanks.

olliehopnoodle 04-02-2014 08:29 PM

So you can drive it around for however long with no issues but once you turn the engine off (after going a few miles) it will not start for about 1/2 hour? Never a problem with a cold start. No codes.
And when you crank it, it 'cranks' fine but just doesn't start? Is this a good summary? And it is very consistent?

JeepOwner33 04-02-2014 08:57 PM

Exactly the issue
 
I have driven it 500 miles in one stretch and did not have one single issue. It drives perfectly. Runs smooth. Once its warmed up, and you turn it off... It won't start. It turns over and its like it just won't catch and run. So I let it sit. You can try and try all through out the half hour and nothing. But right at the 25 minute-half hour mark it will turn over and start with no trouble like normal.

I have spent about $900 dollars trying to hunt down this issue over the past year with no luck. At the moment I am thinking either the Cam Sensor or Coil packs are malfunctioning once they are warm, but I am just not sure. I am not much of a car guy, and when my issue stumps 2 shops and a dealer... what can you do?

olliehopnoodle 04-03-2014 11:24 AM

Let's determine if it is spark or fuel. Get a can of 'starting fluid' from your local auto supply. When the libby won't start, spray some of the starting fluid into the air intake. Try to start it. If it runs for a second or two you most likely have a fuel issue. If it doesn't run you probably have a spark issue. If it doesn't run, try it a few times in a row. wear safty goggles as a backfire might occur.

If you find it is a fuel issue one thing you can try is getting a automotive stethescope (spelling?). While the engine is running listent to one of the injectors. You can actually hear them operating. When you are having the problem listen to them while you are cranking to see if you can hear them operating.

tjkj2002 04-03-2014 12:09 PM

Quote:

Originally Posted by olliehopnoodle (Post 21831417)
Let's determine if it is spark or fuel. Get a can of 'starting fluid' from your local auto supply. When the libby won't start, spray some of the starting fluid into the air intake. Try to start it. If it runs for a second or two you most likely have a fuel issue. If it doesn't run you probably have a spark issue. If it doesn't run, try it a few times in a row. wear safty goggles as a backfire might occur.

If you find it is a fuel issue one thing you can try is getting a automotive stethescope (spelling?). While the engine is running listent to one of the injectors. You can actually hear them operating. When you are having the problem listen to them while you are cranking to see if you can hear them operating.

Never use starting fluid on a gas engine,more so a fuel injected gas engine.Bad,bad,and oh so bad.

Bnova 04-03-2014 02:12 PM

Quote:

Originally Posted by olliehopnoodle (Post 21831417)
Let's determine if it is spark or fuel. Get a can of 'starting fluid' from your local auto supply. When the libby won't start, spray some of the starting fluid into the air intake. Try to start it. If it runs for a second or two you most likely have a fuel issue. If it doesn't run you probably have a spark issue. If it doesn't run, try it a few times in a row. wear safty goggles as a backfire might occur.

If you find it is a fuel issue one thing you can try is getting a automotive stethescope (spelling?). While the engine is running listent to one of the injectors. You can actually hear them operating. When you are having the problem listen to them while you are cranking to see if you can hear them operating.

Quote:

Originally Posted by tjkj2002 (Post 21833001)
Never use starting fluid on a gas engine,more so a fuel injected gas engine.Bad,bad,and oh so bad.

Yep! I was wondering how long it would take for that response to come. LOL:)

olliehopnoodle 04-03-2014 07:28 PM

Why? I use it all of the time, no issues.


http://www.gumout.com/ourProducts/starterFluid.asp

http://www.valvoline.com/products/co...tarting-fluid/

http://www.autozone.com/autozone/acc...fier=7877_0_0_

http://www.autozone.com/autozone/acc...er=525386_0_0_

http://en.wikipedia.org/wiki/Starting_fluid

I will adjust my answer, spray it into the throttle body. It doesn't take much, just a second or two. Unless these guys come up with a factual reason not to try.

Do not spray it while you are cranking it and do not spray it to keep the engine running.

grnd93 04-03-2014 07:36 PM

A lot safer on a gas engine than a diesel. If used cautiously he will have no issues.

tjkj2002 04-03-2014 07:47 PM

Quote:

Originally Posted by olliehopnoodle (Post 21844785)
Why? I use it all of the time, no issues.


http://www.gumout.com/ourProducts/starterFluid.asp

http://www.valvoline.com/products/co...tarting-fluid/

http://www.autozone.com/autozone/acc...fier=7877_0_0_

http://www.autozone.com/autozone/acc...er=525386_0_0_

http://en.wikipedia.org/wiki/Starting_fluid

I will adjust my answer, spray it into the throttle body. It doesn't take much, just a second or two. Unless these guys come up with a factual reason not to try.

On multiport FI engines like used in a KJ,and any vehicle made after '96 is they are dry intakes.Adding highly combustible fuel into the intake can ignite and if you look at your typical intake manifold it's plastic.

Fire and plastic,well you get the point.

Oh and on throttle by wire TB's stuff like that can take off the special coating and cause issues that require the whole TB to be replaced.

olliehopnoodle 04-03-2014 07:49 PM

Okay, I researched some more (if you call reading opinions on the web research). It burns fast and if you overuse it you can take out the engine. Your call. I will continue to use it when needed.

olliehopnoodle 04-03-2014 07:53 PM

Quote:

Originally Posted by tjkj2002 (Post 21845353)
On multiport FI engines like used in a KJ,and any vehicle made after '96 is they are dry intakes.Adding highly combustible fuel into the intake can ignite and if you look at your typical intake manifold it's plastic.

Fire and plastic,well you get the point.

Oh and on throttle by wire TB's stuff like that can take off the special coating and cause issues that require the whole TB to be replaced.

That makes sense. You are correct and the liberty has a plastic intake so a backfire into the intake might have some bad results. I appreciate you clarifying your 'bad bad bad' statement.

OP, your call. If you overspray or there is an ignition source in the intake (backfire or otherwise) you might end up with more damage.

Bnova 04-03-2014 07:58 PM

Quote:

Originally Posted by olliehopnoodle (Post 21844785)
Why? I use it all of the time, no issues.


http://www.gumout.com/ourProducts/starterFluid.asp

http://www.valvoline.com/products/co...tarting-fluid/

http://www.autozone.com/autozone/acc...fier=7877_0_0_
just out of curiosity, why would you use it all the time??
http://www.autozone.com/autozone/acc...er=525386_0_0_

http://en.wikipedia.org/wiki/Starting_fluid

I will adjust my answer, spray it into the throttle body. It doesn't take much, just a second or two. Unless these guys come up with a factual reason not to try.

Do not spray it while you are cranking it and do not spray it to keep the engine running.

just for curiosity sake, why would you use it all the time?

olliehopnoodle 04-03-2014 08:11 PM

All of the time is probably an overstatement. ;) It's not like I use it everyday. But I have both my 82 Jeep and an older Mustang that I rotate in storage. Often they will sit for a month or two or even longer. If it has been more than a month or so I will use it to get the engine going. I usually crank it for about 5 seconds, if it doesn't start I squirt a little starting fluid. Just a couple of quick bursts does the trick.


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