'06 Liberty 3.7L 4x4 - Cranks with no start

[DaveVella1]

Hey everyone,

I recently purchased a 2006 Jeep liberty 4x4 limited. It's the 3.7L gas engine for reference. I'll keep this short:

Vehicle has had Fuel pump, and Starter replaced and the Battery is new.
When I go to start the vehicle after it has sat for more then 30 mins or so, it will start up no problem. The idle on the vehicle is steady at 600Rpms when I start it, after it's been down the highway, etc. ONCE I've driven it for any short or long period of time and I turn the vehicle off, I will need to wait for at least 30 mins to turn it back on.

If I do not wait, it will crank with no issues, no lights dimming, etc. but it will not start.

To further this, I pulled my dip stick and it smells strong of gasoline indicating a lean run. Removal of the sparks (NGK) further indicates a lean run.

The only other item I can mention is that the alternator is beginning to whine (ordered part to replace) but doubt this to be the issue.

Anyone have any idea's of what this can be? In a week I have the following parts coming to see if they fix the issue:
Spark plugs
Coils
Alternator
Camshaft sensor
Crankshaft sensor
PCV valve
Air filter (because why not)


Thanks everyone and I will keep you all updated on what I find as I've spent days now looking through threads with so many almost identical issues but no resolves other than fuel pump.. which I've replaced.

 

[Big Al]

Just by what you said and your getting fuel in your oil, you may have a ring job in the near future.
Compression test and a leak down test will confirm this.

 

[DaveVella1]

I'm going to do the tests next Friday and will let you know. The oil is not running off the dipstick, pretty much the typical consistency which wouldn't indicate to much gas getting in. Hopefully it's more of a lean issue and not ring because no one wants to be doing that job haha!

 

[LibertyTC]

Welcome Davevella1.
Yes compression test it/ leak down.
If you have a strong smell of gas on the dipstick, it would be a rich mixture condition.
Have you had an engine light on, or scanned for any codes lately?

 

[DaveVella1]

Test will be done and I'll let you know.
No engine light at all nor any codes at any point. I've changed the crank and crank sensor along with the PCV valve today and still have the issue.

I'm getting my hands on a multimeter to read my battery again. I have a suspecion the dying alternator has a part in this. After driving it today post installs of the sensors I tested it. Turned it off and tried to turn it back on. As always it failed but I found my interior dome light and head lights dim considerably when I cranked it.

Never had it so noticable before so I'm thinking my whining alternator was worse than expected.

 

[LibertyTC]

Jeep won't like any low voltage conditions at all. Use a battery charger if you have one.
What brand of battery & how many CCA (cold cranking amps) is your battery rated at?
Yes VOM meter is a necessary tool. What it the output voltage reading when running?
After sitting then for 20 minutes parked, doors closed nothing on, what is the voltage reading then?

 

[DaveVella1]

I failed to look at the brand of battery however I have some answers:
Output voltage is 14.5-14.9 when running
After parked nothing on 12.27

It's odd though, if I let the car sit over night once more and tested it at 12.4. I realize the battery is about 50% charge and I will replace it but I don't believe I'm having a battery issue as the alternator is working fine (just replaced it this week) and still having a issue of starting when the jeep has ran (i.e. the motor is hot).

 

[LibertyTC]

Your state of charge at 12.27 is is about 65%. Charge your battery up.
If replacing battery consider that AGM Batteries are more powerful & recover better as they are deep cycle.
AGM are also better sealed & wont corrode your terminals.
Your gas cap is it a Mopar cap? I wonder if it is not sealing or pressurizing properly. Try a new cap...

 

[DaveVella1]

View media item 6677View media item 6676View media item 6675View media item 6674View media item 6673View media item 6672Hey again, Lots has been discovered since you've responded but unfortunately no cure has been haha!
Here's the update:

Purchased and installed the following; Fuel tank cap, Vapor canister solenoid, 6 Sparks, 6 coils, Crankshaft sensors, Camshaft sensors, PCV valve, Fuel pump, Starter, Alternator (not installed yet), MAP sensor (not installed yet), 6 fuel injectors (not installed yet), Temperature coolant sensor.

Battery info: Charged to about 93% now - Motormaster 1933, Cranking 850, Cold crank 690, Reserve 110.
No corrosion and all wires look good.

Fuel line pressure: 50-51psi, turn the engine off and after 15 mins its held pressure minus about 5-6psi.

***Edit, after taking the jeep for a run with the wife, I came home and parked it. Turned it off and did the new fun thing of seeing if it would turn back on, big surprise it did not. I immediately threw my pressure gauge on the fuel rail while it was off but key to on position and it only read 20psi. Is this normal? Should I be looking for a vacuum leak or could a faulty injector cause this?

For the longest time I've been focusing on 'heat' being the culprit as in thinking when the engine heats up there's something going wrong. I think I've gone about this wrong and believe it's a injector issue causing a flooding problem. Volt wise I'm standard across all 6 injectors but I'm thinking one is flooding the engine as all other ignition components sound fine. It's cranking easily, spark is there, coils are new, but I have noticed when it won't start my oil dipstick has a slight odor of gas. Any comments or suggestions?

I'll keep you posted next week when I receive and install the remaining parts. If you have any other tests I should try in the meantime let me know please because after these next installs I fear I'm out of ideas.

I'll attach some photos for reference.



p.s. I'm really looking forward to when I can post pictures and comments about all the cool S*&% I add to it and not just issues -_-

 

[sleazy rider]

*sigh*

Charge the battery to 100%. Full stop. Fuel injection systems are sensitive to battery state. Quit throwing parts at it and potentially introducing other issues. Diagnosis is what you need to do. That starts with the battery ready.

 

[DaveVella1]

*sigh*

Charge the battery to 100%. Full stop. Fuel injection systems are sensitive to battery state. Quit throwing parts at it and potentially introducing other issues. Diagnosis is what you need to do. That starts with the battery ready.

I agree that the battery is where to start. I've swapped my battery out with a friends battery (3 week old NAPA Legend premium AGM) and tried both cold start, after a short drive, and longer drive over a day's period and still ran into the same issue unfortunately.

 

[uss2defiant]

what's the battery voltage after the swap and after the drives?

 

[daves06lrenegade]

I would suggest having a mechanic with a true OBDII reader/scanner look at the signals at the cam and crank sensors both when cold and hot...
Or do it yourself...
A small O'Scope that can read up to 200khz should be able to "see" the cam and crank pulses that are usually under 10khz...
https://www.ebay.com/itm/New-2-4-LC...559480?hash=item2af75af3f8:g:Up4AAOSw2SVfUMNn

Also check or have have him check for fuel injector signals at the PCM...
They are known to be heat sensitive... The big problem is you MUST get the replacement programmed to the car's VIN#
Dave

 

[Duster]

I was gonna guess PCM also.

But since that is already a guess, next time it won't start like that go in the fuse box under the hood and swap the ASD relay with the one just like it next to it. See what happens.

 

[DadOSix]

View media item 6677View media item 6676View media item 6675View media item 6674View media item 6673View media item 6672Hey again, Lots has been discovered since you've responded but unfortunately no cure has been haha!
Here's the update:

Purchased and installed the following; Fuel tank cap, Vapor canister solenoid, 6 Sparks, 6 coils, Crankshaft sensors, Camshaft sensors, PCV valve, Fuel pump, Starter, Alternator (not installed yet), MAP sensor (not installed yet), 6 fuel injectors (not installed yet), Temperature coolant sensor.

Battery info: Charged to about 93% now - Motormaster 1933, Cranking 850, Cold crank 690, Reserve 110.
No corrosion and all wires look good.

Fuel line pressure: 50-51psi, turn the engine off and after 15 mins its held pressure minus about 5-6psi.

***Edit, after taking the jeep for a run with the wife, I came home and parked it. Turned it off and did the new fun thing of seeing if it would turn back on, big surprise it did not. I immediately threw my pressure gauge on the fuel rail while it was off but key to on position and it only read 20psi. Is this normal? Should I be looking for a vacuum leak or could a faulty injector cause this?

For the longest time I've been focusing on 'heat' being the culprit as in thinking when the engine heats up there's something going wrong. I think I've gone about this wrong and believe it's a injector issue causing a flooding problem. Volt wise I'm standard across all 6 injectors but I'm thinking one is flooding the engine as all other ignition components sound fine. It's cranking easily, spark is there, coils are new, but I have noticed when it won't start my oil dipstick has a slight odor of gas. Any comments or suggestions?

I'll keep you posted next week when I receive and install the remaining parts. If you have any other tests I should try in the meantime let me know please because after these next installs I fear I'm out of ideas.

I'll attach some photos for reference.



p.s. I'm really looking forward to when I can post pictures and comments about all the cool S*&% I add to it and not just issues -_-

I don’t understand the percentages on your battery status. Where does this number come from?

further, i think you are close to solving this.

think about your fuel psi.

was 50ish. Key off, gage installed. No start but only 20psi.
I dont think that is enough for the injector to feed fuel to the cylinder.

agree with ****** Rider. Stop the parts cannon and work thru the diagnosis.

 

[DaveVella1]

Hey everyone,

I'm still here working away trying to solve the issue. To answer, my battery is now running at 13.3v now thanks to the friends 'gift'.
Injectors were changed over the weekend which definitely helped with my rich starts, no longer gas vapor smell coming through on cold starts (a win!).
Running I have 53psi, not running but on I have 34psi after the motor has been off for appx 10 minutes. Am I losing pressure to quickly?

Revelation also happened today. I had typical crank no start issue after a 1hr run around the city. Went to hook up to the fuel rail and used the release valve on the gauge to bleed off about 1oz of fuel. The car started right up afterwards. Tried the test once more by turning engine off and waited 5 mins. Typical crank and no start. Bled the gas/pressure again and again I had it fire up fine..

Forget about the fact that when I bought the jeep a month ago I saw them with the tank dropped 'replacing' the fuel pump. I'm curious on your thoughts.