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Hi there guys I have a GC 2016 3.6 with 60k I just bought used with all services done at the dealer. Today I was driving a bit hard and noticed when I got a stop that I can feel the rpms drop for a few second randomly every maybe 1 or 2 minutes.

Then when the car try to take the hight if the i press the pedal the engine shakes a in small amounts and seems like not much power like the car running too rich. It starts to happens most of the time above 30mph. Then it's noticiable when I'm too low on rpms on high gears and I accelerate.

No cel, at least al the vaccum hoses are fine, but oil looks perfect
 

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It's very unlikely to have a bad coil causing misfires and not get a CEL. The misfire codes and CEL are triggered by the Crank Position Sensor noticing a difference in crank speed between cylinder firings, so basically anything causing a misfire can light the cel. But a bad coil would definitely cause the type of misfire that would quickly be picked up and light a CEL.....

Check you fluids, if you have a headgasket leak, you could be low on coolant. The only way to check coolant properly is to remove the pressure cap from the radiator and check the fluid is within an inch of the where the pressure cap seals.... ONLY DO THIS WHEN THE ENGINE IS COLD

Check for Vacuum Leaks, but a big vacuum leak will light a CEL....

Fuel Injector Cleaner couldn't hurt, as well as cleaning the throttle body.....

If you can check fuel pressure.....

Both the 3.6L and the HEMI have had follower arms or lifters fail, that can damage the cam and cause a valve for one cylinder not to open fully. This will cause rough running at first and eventually would cause misfires.....

At the same time, the WK2 uses hydraulic engine mounts... ...they typically only last 60k miles.... ....so nothing could be wrong with the engine, but the bad motor mounts would let more vibrations through to the chassis.... ...but engine mounts couldn't cause the engine performance or rpm problems you're reporting...
 

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Discussion Starter #3
It's very unlikely to have a bad coil causing misfires and not get a CEL. The misfire codes and CEL are triggered by the Crank Position Sensor noticing a difference in crank speed between cylinder firings, so basically anything causing a misfire can light the cel. But a bad coil would definitely cause the type of misfire that would quickly be picked up and light a CEL.....

Check you fluids, if you have a headgasket leak, you could be low on coolant. The only way to check coolant properly is to remove the pressure cap from the radiator and check the fluid is within an inch of the where the pressure cap seals.... ONLY DO THIS WHEN THE ENGINE IS COLD

Check for Vacuum Leaks, but a big vacuum leak will light a CEL....

Fuel Injector Cleaner couldn't hurt, as well as cleaning the throttle body.....

If you can check fuel pressure.....

Both the 3.6L and the HEMI have had follower arms or lifters fail, that can damage the cam and cause a valve for one cylinder not to open fully. This will cause rough running at first and eventually would cause misfires.....

At the same time, the WK2 uses hydraulic engine mounts... ...they typically only last 60k miles.... ....so nothing could be wrong with the engine, but the bad motor mounts would let more vibrations through to the chassis.... ...but engine mounts couldn't cause the engine performance or rpm problems you're reporting...
Thanks, coolant are perfect, there is no sign of water on the oil.
Right now if i start the engine there is no check engine and ess icon, but the car doesn't run fine when driving, at idle is fine.
 

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Today i double check the vacuum hoses, connection to the maf, etc. Its hard to explain but it feels like you try to accelerate and in front of you is a truck stopping your car. If you accelerate gently on the pedal is fine but when you load the engine with gas is start to shake or feels weird.
 

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It all boils down to the duration of the misfire wether the PCM chooses to ignore it or not. Recreate the condition that causes the misfire for appx 10 seconds. While this isn't the proper way to diagnose it, that should set a code and at least help you identify the problem cylinder.
 

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We didn't factor in low voltage. That's an entirely different can of worms that can open up. Definitely time for a battery. That's mildly premature for a battery failure though.
 

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Discussion Starter #11
Well autostart works again with the new battery. Car runs better but when you flood the pedal is start to fail again, no codes, no nothing. Bad alternator that affect the fuel system?
 

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The battery disconnect has most likely reset most of the rediness monitors. Several drive cycles will need to be completed before any faults are detected.
 

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Hi there guys I have a GC 2016 3.6 with 60k I just bought used with all services done at the dealer.....
Are you in Africa? I noticed a flag in your avitor that appears to be African....

Bad Fuel, Leaded Fuel or clogged catalytic converters are a possibility to consider.

In the U.S. the quality of the fuel supply has improved to the point that bad gas causing problems is just about unheard of..... ....so most of us on this forum are from the U.S. and we don't even consider the possibility of bad fuel causing problems........

Not so in many other Nations.... ...I suspect Europe might be the same as far as quality and tight control of the fuel supply..... ...but many developing nations, all sorts of things could be going wrong..... ...and no offense meant by developing nation, just stating a Nation not as developed in Industry as much as the original Industrialized Nations....

When I was in Iraq, we got bad fuel from a local supplier for our admin vehicles, with the modern fuel injection systems and catalytic converters they started displaying the same symptoms you're complaining of. As well, some places still use leaded fuel, which will destroy catalytic converters and can clog them, which your symptoms could be clogged catalytic converters.... ....bad a catalytic converter would fail its OBDII test and light a CEL with a stored code.... ....of course if you have an export model, that would not have to meet OBDII and thus it might not have that feature.....

There was another poster from Africa talking about modifying his WK2, that stated his Catalytic Converters were clogged... ...I think it became clear that was not his problem and he was just looking for an excuse to buy an aftermarket exhaust and get rid of the catalytic converters.....
 

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Does the Dealer charge you to read fault codes? Cause you know there are several tools out there to do it yourself, that cost less than a single Dealer visit......

You can have stored Fault Codes and not light a CEL, especially misfires, it has to suffer a certain number of misfires within a certain amount of time to light the CEL, and the CEL will go out if go long enough without more misfires.....

From the symptoms you describe, for it to be misfires causing them, they would be severe and often enough that they would surely light a CEL, if the misfires were the cause and/or a major contributor... ....so the CEL not lighting, is a little baffling for a problem like this.....

Also keep in mind, if you're outside the U.S., then you may have an export model that has meet different rules and standards, and what sets off a CEL may be programmed different because its export and we advising you are doing based off our experience with the U.S. Domestic version of the WK2......
 

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Discussion Starter #18
Does the Dealer charge you to read fault codes? Cause you know there are several tools out there to do it yourself, that cost less than a single Dealer visit......

You can have stored Fault Codes and not light a CEL, especially misfires, it has to suffer a certain number of misfires within a certain amount of time to light the CEL, and the CEL will go out if go long enough without more misfires.....

From the symptoms you describe, for it to be misfires causing them, they would be severe and often enough that they would surely light a CEL, if the misfires were the cause and/or a major contributor... ....so the CEL not lighting, is a little baffling for a problem like this.....

Also keep in mind, if you're outside the U.S., then you may have an export model that has meet different rules and standards, and what sets off a CEL may be programmed different because its export and we advising you are doing based off our experience with the U.S. Domestic version of the WK2......
Hi there yes im at the dealer. The car came with no codes but with the syntoms. I guess it came like that cause yesterday I replace the batteries. Then they check the codes and no issues, drove again the car with a dealer mechanic and the engine throw p0306. Here to scan the car is approximately $35 usd. I know a few people on my local dealer so they made a discount.
 
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