Major issue with PenStar 3.6L Cylinder # 3 reads PO303 code and misfires. Replaced plugs, coils, plenum gaskets, throttle body gasket & # 3 injector since it sounded bad. Took the car to 2 Chrysler dealerships paid $185.00 diagnostics test and was told I used aftermarket plugs and coils and that was the issue. Dealer wanted $1,700.00 to fix and hold the car for several days? I purchased the Mopar plugs, plenum gaskets and 1 coil pack is what they told me I needed. Replaced everything and the issue never went away after spending $660.00.
Did some more research on the net and other places and found this has been an issue for some time with this 3.6 PenStar. Took the car to another Chrysler dealer who told me they needed to do their own diagnostics test even though I had one done 2 days ago pure bullshit. Could not get rid of the code or the misfire car ran fine with the exception of the rough idle. I purchased a PDM and had it programed for the vin of the car $245.00 since this cleared the issue for someone else. Installed the PDM and had the same issue. Reinstalled the original PDM back in the car. Also checked for any vacuum leaks, cleaned the TCM since that seems to cause issues also. At this point I am waiting to see if I can get a trusted mechanic to look at it and it won't be Chrysler $35.00 per Mopar plug and $84.00 per coil and it did not fix the issue. Chrysler needs to step up and address this issue. I have been a Mopar fan since I was a kid but this crap is total lack of customer service.
Update from Nov 30, 2023: Had the 300 into another mechanic. Apparently, the oil filter assembly was leaking oil inside the engine causing low pressure that would not allow the valves to close. I was informed they needed to repair this before going any further. Repair cost was $1,018.00 which included another diagnostic test. Everything was installed and still #3-cylinder PO303 code. Mechanic said this is a known issue with the 3.6L where the valve seats are bad. There are recall bulletins out there but not one for the 2014 Chrysler 300. he only option was to replace he engine. Refractured engine is about $3,500.00 plus labor plus the other money I had spent so it's not worth having it done. The mechanic said to go after the dealership / Chrysler but at this point I think that's a waste of time the car will be sold for parts which is a darn shame since everything else is in great shape. If you get that PO303 code and the plug and coil change does not fix it be careful not to spend any more money trying to fix it. Chrysler has lost my business I will never buy another Chrysler, Jeep, Dodge or any other product the make.
A D V E R T I S E M E N T S
Major issue with PenStar 3.6L Cylinder # 3 reads PO303 code and misfires. Replaced plugs, coils, plenum gaskets, throttle body gasket & # 3 injector since it sounded bad. Took the car to 2 Chrysler dealerships paid $185.00 diagnostics test and was told I used aftermarket plugs and coils and that was the issue. Dealer wanted $1,700.00 to fix and hold the car for several days? I purchased the Mopar plugs, plenum gaskets and 1 coil pack is what they told me I needed. Replaced everything and the issue never went away after spending $660.00.
Did some more research on the net and other places and found this has been an issue for some time with this 3.6 PenStar. Took the car to another Chrysler dealer who told me they needed to do their own diagnostics test even though I had one done 2 days ago pure bullshit. Could not get rid of the code or the misfire car ran fine with the exception of the rough idle. I purchased a PDM and had it programed for the vin of the car $245.00 since this cleared the issue for someone else. Installed the PDM and had the same issue. Reinstalled the original PDM back in the car. Also checked for any vacuum leaks, cleaned the TCM since that seems to cause issues also. At this point I am waiting to see if I can get a trusted mechanic to look at it and it won't be Chrysler $35.00 per Mopar plug and $84.00 per coil and it did not fix the issue. Chrysler needs to step up and address this issue. I have been a Mopar fan since I was a kid but this crap is total lack of customer service.
Update from Nov 30, 2023: Had the 300 into another mechanic. Apparently, the oil filter assembly was leaking oil inside the engine causing low pressure that would not allow the valves to close. I was informed they needed to repair this before going any further. Repair cost was $1,018.00 which included another diagnostic test. Everything was installed and still #3-cylinder PO303 code. Mechanic said this is a known issue with the 3.6L where the valve seats are bad. There are recall bulletins out there but not one for the 2014 Chrysler 300. he only option was to replace he engine. Refractured engine is about $3,500.00 plus labor plus the other money I had spent so it's not worth having it done. The mechanic said to go after the dealership / Chrysler but at this point I think that's a waste of time the car will be sold for parts which is a darn shame since everything else is in great shape. If you get that PO303 code and the plug and coil change does not fix it be careful not to spend any more money trying to fix it. Chrysler has lost my business I will never buy another Chrysler, Jeep, Dodge or any other product the make.
- Graham K., Wake Forest, US