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Hello, my brother has a 07' 2.2 that turns over but won't start. Car has 170k on it and was running good until it didn't start the other morning.

The first thing I tried was to pull any codes but the scan tool wouldn't connect, found a blown fuse (radio I think) and now the tool connects and I can get the live data but there's no codes stored.

Second I hooked up a fuel pressure gauge and it's getting around 50-55psi.

I used a spark plug light and all 4 cylinders have spark, then tried spraying starting fluid in the throttle body but won't fire. I replaced the plugs too but still nothing.

At this point I was sure it had a broken timing chain so I pulled the valve cover but everything seems okay, chain is tight and the camshaft moves freely when you turn it over.

The only thing I think it could be is a bad crankshaft position sensor that's throwing off the timing so bad that it won't even fire with the starting fluid but I wanted to get your opinion before we start spending money because my brother is a broke college student. Thanks in advance for any help!
 

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Bad crankshaft sensor is your most probable cause.
 

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Bad crankshaft sensor is your most probable cause.
Thanks for the reply! I found the sensor locally for $25 so going to swap it this weekend and go from there. What really has me puzzled is why I couldn't connect to the ECU at first, not sure if a bad sensor could blow the fuse but it worked fine a couple months ago when he had a emissions code from a vacuum leak.
 

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Replaced the crankshaft and camshaft sensors and still no go. Also checked every fuse under the hood, on the side of the console, and the main 50 amp one in the trunk. I'm guessing something in the ECM may have been damaged when the fuse blew but if anyone has any other ideas I really appreciate it.
 

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After checking the signal to the coils it appears the ignition module is bad, all the coils fire but it seems to go in a almost random pattern and nowhere close to when a piston is topping out on a compression stroke. I know the module is in the ECU on the 07' and was wondering if I can just swap in a used one from a identical car or will it need reprogramming?
 

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Even a used one will need a flash. Could also be a cam position sensor but hard to tell with no code. ECM needs both crank and CAM sensors to determine firing order and timing.
 

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Picked up ecu and got it unlocked using the key method but still won't run. I replaced the cam sensor when I did the crank one. I think it's time to throw in the towel and bring it in because I'm out of ideas.
 

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So we decided to take another look at the engine before putting the valve cover back on and it appears the timing chain jumped by 3-4 teeth, not sure if there's any damage to the valves but it looks like the intake valves are open at least a little on the firing stroke so there's no compression.
 

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So after pulling the timing cover it's now apparent that it jumped way more than a few teeth, just looking at the top it looked like it was only a few teeth off between cams but the crank is almost 180° off from the top end so it had to do some damage. Going to let him decide if we should start looking for a used long-block or just scrap it because the car needs everything like brakes, struts, and tires.
 
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