Chrysler 300 crank no start no codes checked most everything?

So my chrysler 300 is in a crabk no start condition. I changed the crankshaft position sensor, changed the throttle body, and the accelerator pedal, changed the spark plugs and coil packs, checked the injectors, changed the o2 sensors, changed the coolant temperature sensor. The throttle body, accelerator pedal, coil packs, o2 sensors and coolant temperature sensor were all changed in response to codes i recieved from my OBD2 scanner. The rest i changed based on symptoms and somewhat educated guesses. Another relevant detail, is that i have no compression in one cylinder. The rest are all fine. It is a 6 cylinder engine so i would expect it to run nonetheless. I recently noticed that my EGR valve TUBE was loose and missing the gasket. I remedied that. I have reset my throttle position sensor after each thing i have changed. I got the car in a no start condition. It had sat for 11 months. I completely emptied the fuel system and replaced the fuel with good fuel. The air filter in like new. The only other tbings i could think of are my cam shaft posotion sensor or my ECU. i was under the impression that the cam shaft position sensor alone would not cause this problem. But maybe in combination with the bad cylinder? Does anyone have any advice on what could be causing this issue? I have basically no money to work with so , im going to have to collect change and borrow from friends in order to pay for whatever i change next. So id like to be corre t if possible. I need to get this car fixed so that i can have reliable transport to the job im starting next week. Thanks in advance!!

For an engine to start requires fuel, air, spark and compression. You addressed the #2,3, and 5/6ths of #4. What about #1, fuel supply and pressure?

Squirt some starter fluid into the throttle body while it is cranked. If it starts and runs only as long as you are spraying, your fuel supply is not functional. Could be a pump, could be a relay, could be wiring.

If you get this running, it will not be reliable. Period. The engine is bad.


You checked compression. But can’t can’t check fuel pressure?

That means the battery died.

Does the car have a anti-theft system?

If so, that needs to be reset for the engine to start.



Those 3.6L Pentastar engines are known for having internal engine failure and being that you have no compression in one cylinder and no money, you are probably better off investing your money on something else that runs…

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Well, OP has replaced a lot. I’d have quit when I saw zero compression.

I have little to add except the first thing is to check for fuel pressure and spark. Whatever is missing sends you down a different path. If you have neither then the security system might do that but I don’t know. I’m not a mechanic. Then there is a,ways the timing if the chain sheared a sprocket but that is kinda drastic. If you can peek through the oil filler or something to see if the lifters are moving when cranking, that at least says there is some chain.

Back to why the car was parked in the first place for almost a year.

I have tried spraying statter fluid into the throttle body and it makes no difference. I have changed batteries to a good charged battery. I dont know anything about the antitheft system though. Does anyone know how to adress that? And im aware it wont ever be a reliable car, i just need to it to run for a short time so i can get a few paychecks in and either replace the engine or get a different car.

I read the post on how to reset the antitheft system, and i have already changed the battery, and thebcar does crank and definitely responds and there is not antitheft system light on the dash blinking. So i do not believe this is the issue.

Also, i wasnt able to check fuel pressure because i cant seem to find the shrader valve or a proper location to place a T valve for fuel pressure testing, however i know it is getting fuel bevause the spark plugs had fuel on the tips , so i know its getting gas. Might have flooded at some point but i have let it sit and tried again without pressing gas as well. One thing that might be relevant is that when i press the gas pedal or pump it, there is intermittently the sound of it almost turning all the way over like the sound of it sparking and everything but only sometimes. It did start and idle one time after i first changed the spark plugs but i turned it off after letting it idle for a few minutes to go grab my coat to take it on a test drive and then would not start again afterwards.

And the car was parked for so long because the previous owner said it had stalled out on a hill and they had another vehicle so they didnt bother looking into it.

Also its a 2.7L not a 3.6L.

I cant seem to find any shrader valve, and theres akso no spot to put in a T valve that i can find…

If it didn’t respond to the starter fluid then it is likely a spark or compression problem and not a fuel problem anyway. The valve thought I’d ion the fuel rail. You have changed so much that the possibility is a bad part or install on something you have alrespady done. There comes a point though where it is cheaper to have a shop do a diagnosis. But I’m not a mechanic.

I have gone back and triple checked everything i have done on it multiple times in order to rule out that possibility.
To reiterate my original question, does anyone have any thoughts about the camshaft position sensor being the culprit? Or the ECU? I appreciate all the quick responses by the way! Thankyou guys!

One more comment before the pros chime in. Code scanners can be nice but not every problem results in a code. Plus the code only directs the circuit to look at and not the particular problem. Also you can have multiple codes that are ghost codes related to only one problem. Codes need to be cleared with the lower codes first and the higher ones may disappear.

Factory manuals, or their on line versions such as all data, have trouble shooting charts that help to diagnose issues. They may not cover everything but when you get to the bottom with yes/no questions, much has been ruled out. If you are not using one, it’s a good place to start back up.

I’m still wondering about timing and maybe a compression test needs to be done. A timing chain or belt issue would stop a car dead going up a hill. Many of the other items wouldn’t.

What year is this 300?


It’s a 2009

There are no metal shavings in the oil, and the one time I did get it to start and idle there were no unusual sounds to indicate any timing issue… It seemed to me that the crankshaft sensor had gone bad and that was the original issue , I think whatever the issue is now may have been caused by it sitting or something. It might be worth noting that I had tried to start it a few times before changing out the gas because I didn’t think it smelled bad at first, and that the throttle body and spark plugs and O2 sensors were all filthy before I changed them . One of the O2 sensors was even “blown up” for lack of a better description. Like the tip had expanded outwards. The gas has been completely bled out and replaced with fresh gas now and all the parts that I could find with excessive carbon build up have been either cleaned or replaced. I also forgot to mention that I cleaned the MAP sensor with electronic parts cleaner. Not sure if any of that helps to narrow it down…

What exactly was the compression in the cylinders that you said were “fine”? And the one that was dead?

The reason I ask is if I remember correctly there is no Mass Air Flow sensor on this engine. The car calculates fuel requirements largely on input from the MAP sensor. If your bad cylinder has an intake valve issue, that could throw off your intake vacuum enough to cause running problems. Also, I don’t see specifically where you tested and verified good spark. Are you sure you have good spark at the plugs?

That 2.7 is one of the most unreliable engines ever, difficult to repair and not at all durable even when running at its best.

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I changed the spark plugs and coils but no I guess I didn’t actually check that they were getting spark now. I need to use a spark tester thing correct? There’s no DIY way to do it without one is there? Like with a multimeter or something? I guess I just assumed they were getting spark because the one time I actually did get it to start and idle, was right after I put the new spark plugs in…
the compression on 5 of the 6 cylinders was roughly 120, with 2-4 of that. (119-123) and the compression on the one cylinder was 0.
I didn’t – and don’t – think this is relevant but might as well throw it out there: At the time of compression test, which was before changing the plugs or coils or anything else; the only thing I’d changed at that time was the crankshaft position sensor; the coil in the cylinder with bad compression was almost completely broken at the tip, like the rubber boot, with spring attached, was hanging onto the rest of that coil, by a figurative thread. When I got around to changing the coils it was completely broken off and I had to reach in with very skinny tweezer things and grab it to remove it. But Im pretty sure that wouldn’t effect compression since the coils and plugs are to be removed to perform the test. But I could be wrong, please correct me if I am. Also I just saw a video in which the guy was saying that to preform a compression test you’re supposed to pull out all the spark plugs at once and then test with all 6 removed? Is that accurate? Because I was under the impression that you are supposed to leave all of them (the spark plugs) installed and pull only the one you are testing out at a time. I’m sorry for all the confusion and for if these seem like supid questions. And I know it might sound like a waste of time to get it running when I’m going to have to replace the engine anyways, but I literally just need it to run for long enough to get a couple paychecks under my belt so I can afford to get a used engine and do the swap. So any advice on how to get it running (even if it is only temporarily) is greatly appreciated. Otherwise, yeah I understand that it’s a terrible car and that getting it running with a bad cylinder is not a permanent fix. Thankyou. <3