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Unread 10-27-2012, 01:55 PM   #16
2005WK37David
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2005 WK 
 
Join Date: Oct 2012
Location: Hickory, NC
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Switched back to 10% ethanol gas, and the first time I gave it the option to let me down it did. Let it sit for about 30 minutes after running for a while, then came back to start it, and same issue. Engine compartment up to 150 degrees near the fuel rail.

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Unread 04-08-2013, 02:20 PM   #17
BigRick
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I know its been a while since this posting - But I had this exact same problem w/ a 2001 Lincoln LS I had - Ended up being a leaky fuel injector. Essentially, the injector would leak fuel into the cylinder after shutting down the engine. Leaked in the first 30 mins after shutting off the motor - after that the pressure would equalize and it would stop. In the 10 to 30 mi range, the motor was essentially flooded and wouldn't start. After sitting for several hours, that leaked fuel would evaporate and it started fine. It took the dealer to figure out which injector was leaking, but after they fixed it, never had another problem.

Maybe in your case the ethanol leakes past an o-ring or something, I don't know but it's worth looking into.
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Unread 04-14-2013, 01:47 PM   #18
2005WK37David
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Since my last post on 10-27-2012, I have driven over 17,000 miles, on ethanol free gas. Every two months i will fill up once with ethanol gas, and will have the same issue, so back to ethanol free gas.

I have read about how ethanol is causing some issues on orings and such, but mainly on small engines, like lawn equipment and such.

I average 15mpg, and it starts every time when using ethanol free gas. It has 337,000 miles on it, and it sounds like it is new, and runs like it is new.
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Unread 11-10-2014, 02:47 PM   #19
Jeep85
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I've been dealing with the same problem for 2 years. Have not tried letting gas out of fuel rail by pressing shrader valve. I usually grab another cold one and it starts every time. The longest its taken to start is 30 min. Just replaced crank sensor with no luck. I've found 4 other threads on other forums with exact same problem but no fix.
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Unread 11-10-2014, 03:08 PM   #20
Jeep85
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Heres a few with same problem. I have a 2005 jeep Cherokee Laredo 3.7L and it seems to be a 3.7L engine problem in the cherokee and liberty models

http://repairpal.com/wont-start-when-hot-311

http://www.jeepkj.com/forum/f196/pro...hen-hot-50905/

http://www.city-data.com/forum/autom...p-liberty.html
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Unread 11-10-2014, 05:52 PM   #21
luckyse7ens
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Quote:
Originally Posted by Jeep85 View Post
Heres a few with same problem. I have a 2005 jeep Cherokee Laredo 3.7L and it seems to be a 3.7L engine problem in the cherokee and liberty models

http://repairpal.com/wont-start-when-hot-311

http://www.jeepkj.com/forum/f196/pro...hen-hot-50905/

http://www.city-data.com/forum/autom...p-liberty.html
It seems to be the early model years?
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Unread 11-11-2014, 07:00 AM   #22
Jeep85
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Yea. If it were a problem with ethonal gas you would think it would be more common.
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Unread 11-12-2014, 04:01 PM   #23
2005WK37David
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Quote:
Originally Posted by Jeep85 View Post
Heres a few with same problem. I have a 2005 jeep Cherokee Laredo 3.7L and it seems to be a 3.7L engine problem in the cherokee and liberty models

http://repairpal.com/wont-start-when-hot-311

http://www.jeepkj.com/forum/f196/pro...hen-hot-50905/

http://www.city-data.com/forum/autom...p-liberty.html

I found this interesting in the first article, "When an engine is hot, and turned off, the fuel that is in the lines and injectors must be kept under pressure to prevent vapor lock. If the pressure drops, the fuel turn from liquid to a gas (vapor) then the fuel pump cannot pump the fuel when trying to start. Have the residual fuel pressure checked."

I now have 403,000 miles on my engine, and just replaced the fuel pump and injectors. I will soon find out if this fixed that problem when I run my first tank of ethanol gas soon.

This might not be an "ethanol" problem, and could have been a fuel pressure problem, but ethanol does have a lower boiling point than regular gas if I remember correctly. So maybe I just experience it with the ethanol gas.

This engine does not have a return fuel line, but after inspecting the fuel rail when I replaced the injectors I found that the fuel enters the drivers side of the rail, and then crosses over to the passenger side. The holes for the injectors on the drivers side are larger diameter than on the passenger side. Also noticed on the passenger side, it looks like there is a baffle in that side that runs the length of the passenger side basically splitting the fuel rail on that side to an upper and lower side, and the baffle has springs between it and the inside bottom of the rail.

As I look back on my previous post from about 80,000 miles ago, I was averaging 15 mpg, but lately I have been averaging 13 mpg, this is why I decided to replace the injectors and clean the injector ports on the heads. Upon doing all this I also noticed that I was only running 35 psi on the rail and at the tank, so I also replaced the fuel pump.

I have only put 150 miles on it since all the work I just did to it, that I posted on another thread. I will be getting it back on the road probably Friday after I finish detailing it. Then will be able to test my ethanol theory.
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Unread 11-13-2014, 11:08 AM   #24
BrooklynWK
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I get the same problem too sometimes in my 05 WK 3.7. I just chalk it up to a hot start issues. Nothing that really worries me I think the fuel just gets to hot and vaporizes a little bit. If it does the start rough idle I turn it off and usually runs fine after another start up right after. I'm in NY on LI and we don't have Ethanol-Free stations otherwise I would only run ethanol free gas...

David, you really have 403K on the motor? I think I was high at 206k! very nice!
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Unread 11-13-2014, 11:11 AM   #25
BrooklynWK
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Quote:
Originally Posted by 2005WK37David View Post
I found this interesting in the first article, "When an engine is hot, and turned off, the fuel that is in the lines and injectors must be kept under pressure to prevent vapor lock. If the pressure drops, the fuel turn from liquid to a gas (vapor) then the fuel pump cannot pump the fuel when trying to start. Have the residual fuel pressure checked."

I now have 403,000 miles on my engine, and just replaced the fuel pump and injectors. I will soon find out if this fixed that problem when I run my first tank of ethanol gas soon.

This might not be an "ethanol" problem, and could have been a fuel pressure problem, but ethanol does have a lower boiling point than regular gas if I remember correctly. So maybe I just experience it with the ethanol gas.

This engine does not have a return fuel line, but after inspecting the fuel rail when I replaced the injectors I found that the fuel enters the drivers side of the rail, and then crosses over to the passenger side. The holes for the injectors on the drivers side are larger diameter than on the passenger side. Also noticed on the passenger side, it looks like there is a baffle in that side that runs the length of the passenger side basically splitting the fuel rail on that side to an upper and lower side, and the baffle has springs between it and the inside bottom of the rail.

As I look back on my previous post from about 80,000 miles ago, I was averaging 15 mpg, but lately I have been averaging 13 mpg, this is why I decided to replace the injectors and clean the injector ports on the heads. Upon doing all this I also noticed that I was only running 35 psi on the rail and at the tank, so I also replaced the fuel pump.

I have only put 150 miles on it since all the work I just did to it, that I posted on another thread. I will be getting it back on the road probably Friday after I finish detailing it. Then will be able to test my ethanol theory.
Interesting to think about I was under the hood poking around on my friends 08 3.7 WK and I was looking for things that were revised. One thing I noticed was that the 08+ rails on the 3.7 looked different, looked like they were a little taller and poss bigger? Wonder if they addressed this issues and changed the rails. Either way I'd fancy doing a swamp to 08+ rails on my 05 if it would be possible. Also have to consider that the 08 is Drive By Wire and mine is cable throttle.
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Unread 11-13-2014, 03:37 PM   #26
2005WK37David
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Quote:
Originally Posted by BrooklynWK View Post
I get the same problem too sometimes in my 05 WK 3.7. I just chalk it up to a hot start issues. Nothing that really worries me I think the fuel just gets to hot and vaporizes a little bit. If it does the start rough idle I turn it off and usually runs fine after another start up right after. I'm in NY on LI and we don't have Ethanol-Free stations otherwise I would only run ethanol free gas...

David, you really have 403K on the motor? I think I was high at 206k! very nice!
Yep, 403,000 miles.

Once this tank runs out, I will try ethanol gas and see what happens.

I was always thinking that the gas was turning to a vapor cause of the lower boiling point of ethanol gas, but according to that article, it could be doing that as a result of low fuel pressure, or fuel pressure bleed off. If the regulator in the pump in the tank is releasing pressure, then I could see it causing this issue.

I am running around 61 psi fuel now.
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Unread 11-18-2014, 07:38 AM   #27
Jeep85
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I tried letting the fuel out of the fuel rail and it started right up. If i drive home (45 min) from work and then try to leave my house within 15-20 min It just keeps cranking and almost starts. But emptying the fuel rail seems to allow it to fire right up.
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Unread 11-19-2014, 03:13 PM   #28
2005WK37David
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Quote:
Originally Posted by Jeep85 View Post
I tried letting the fuel out of the fuel rail and it started right up. If i drive home (45 min) from work and then try to leave my house within 15-20 min It just keeps cranking and almost starts. But emptying the fuel rail seems to allow it to fire right up.
Check your fuel pressure, should be 59 psi +/- 2 psi.

Check it running, and then with it off, should not drop far below that when off.

I found that ethanol free fuel does not cause this issue when pressure is low, but ethanol fuel does.
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