2004 3.7 V6 hard cranking when warm

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Dominic Demico III

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Greetings,


I am new to to forum as well as a new Jeep owner

I recently purchased a 2004 Jeep Liberty with the 3.7 V6 equipped with the 5 speed manual. It has almost 200,000 miles on it. When I was driving it home, I had a check engine light that came on and started to flash. Once home, I found code P0132 (bank 1, sensor 1) oxygen sensor high voltage. I checked wiring and all was good. I put a new NEK sensor in, and instantly codes PASSED and it was running great. Now that I put a few miles on it, all still seemed well.

Now, the new issue (which did happen originally as well) is that once the engine is warm, and go to restart it after 20-30 min, it will hard start and run great, then after another 20-30 min, it will crank but wont turn over, try again, same thing. it takes a good 5 cranks until she purrs. then again its running great. once, it did throw code P0138, (bank 1, sensor 2) oxygen sensor. but now codes are clear and i can expect this randomness to happen. If i start this vehicle the next day cold, she starts right up. this scenario i mentioned above happened today. cold start> drive 50 miles> restart 30 min later> 1 hard crank> drive 2 miles > restart 10 min later> rough 5 cranks to start.> park for the evening

air filter is brand new, cleaned MAF sensor, all tubing clean. No smoke, coolant/oil appear to be separate (no head issue). i will notice a rich smell once awhile at idle.

Any help with this would be greatly appreciated

thank you !!!
 

LibertyTC

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Welcome to the forums.
Many starting issues may be cured by installing new spark plugs.
Use NGK ZFR6F-11G ONLY gap at .040 inch.
You must be registered for see images attach

Fact the ignition on the jeep fires these plugs hot and can eat the gaps. Replace them every 40K miles.
If the coil packs have never been replaced, it may be a good idea to replace all 6 with Mopar ones.
What brand of 02 sensor did you install? Jeep likes NTK o2 sensors only.
To clean/ improve injector performance, I'd also get 2 bottles of Chevron Techron Concentrate and take the jeep for a good long hwy run.
You must be registered for see images attach

Then see how the Jeep runs.
Btw anytime you get a flashing egine light, pull over shut it off, wait, then re-start it.
If it is misfiring, it can damage the engine if you continue to drive with the misfire.
 

gribbled

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I'm having a maybe similar issue with my 05 KJ 3.7L (owned since new). When the engine is cold it starts perfectly, but after being warmed up to normal temperature it will crank fine, catch, than instantly die. This happens if you drive it to a store, go in for a few minutes, and come back out. I don't think anything is overheating or vaporizing as it is winter here (like 30 degrees outside).

The interesting symptom is that if I push the gas pedal down a bit (like 1/2") prior to cranking, then it starts perfectly. I'm wondering if this means it is having trouble getting air?

Plugs are iridium, 15k miles 3 years old. The air filter looks pretty clean. There are no stored codes of any sort.

Any idea where to start? This is a repeatable problem. BTW this is been an amazingly reliable vehicle but only has 127k miles on it now.
 
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Ksat

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Could be a vacuum leak or stuck open EVAP solenoid.
 

tommudd

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I'm having a maybe similar issue with my 05 KJ 3.7L (owned since new). When the engine is cold it starts perfectly, but after being warmed up to normal temperature it will crank fine, catch, than instantly die. This happens if you drive it to a store, go in for a few minutes, and come back out. I don't think anything is overheating or vaporizing as it is winter here (like 30 degrees outside).

The interesting symptom is that if I push the gas pedal down a bit (like 1/2") prior to cranking, then it starts perfectly. I'm wondering if this means it is having trouble getting air?

Plugs are iridium, 15k miles 3 years old. The air filter looks pretty clean. There are no stored codes of any sort.

Any idea where to start? This is a repeatable problem. BTW this is been an amazingly reliable vehicle but only has 127k miles on it now.
One thing get rid of those iridium plugs , customer brought me one , missing at times, hard starting etc
Put in correct spark plugs , NGK coppers first thing and ran better, started everytime, no more issues
KJs do not like iridiums no matter what Autozone etc tells ya

and of course I hear you saying well they been on there 3 years , yes but they have hit that point where they are giving you issues I would say
 

Ugeneste

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Greetings,


I am new to to forum as well as a new Jeep owner

I recently purchased a 2004 Jeep Liberty with the 3.7 V6 equipped with the 5 speed manual. It has almost 200,000 miles on it. When I was driving it home, I had a check engine light that came on and started to flash. Once home, I found code P0132 (bank 1, sensor 1) oxygen sensor high voltage. I checked wiring and all was good. I put a new NEK sensor in, and instantly codes PASSED and it was running great. Now that I put a few miles on it, all still seemed well.

Now, the new issue (which did happen originally as well) is that once the engine is warm, and go to restart it after 20-30 min, it will hard start and run great, then after another 20-30 min, it will crank but wont turn over, try again, same thing. it takes a good 5 cranks until she purrs. then again its running great. once, it did throw code P0138, (bank 1, sensor 2) oxygen sensor. but now codes are clear and i can expect this randomness to happen. If i start this vehicle the next day cold, she starts right up. this scenario i mentioned above happened today. cold start> drive 50 miles> restart 30 min later> 1 hard crank> drive 2 miles > restart 10 min later> rough 5 cranks to start.> park for the evening

air filter is brand new, cleaned MAF sensor, all tubing clean. No smoke, coolant/oil appear to be separate (no head issue). i will notice a rich smell once awhile at idle.

Any help with this would be greatly appreciated

thank you !!!
Check the camshaft and crankshaft position sensors
 

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