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i repaired the wiring and now its has 5.4 vdc at terminal a, terminal b is a good ground, and terminal c also has 5.4vdc. now i have no more po340 but it still doesnt start. the compression is 160 psi on all 4 cylinders. the valves,pistons and timimg chains and gears are all new and set correctly. it has started twice, but it didnt start easy either time. when i removed the spark plugs to see the spark it does have a strong looking purple spark on all 4 plugs. im a harley-davidson mechanic and have been for 40 years, and i know their ecm's dont usually go bad without some warning with hard starting or pinging usually happening before its quits. are these ecu's similar, i ask because this whole thing started with hole being burnt in the pistons. thanks for any help you can offer.

Vehicle: 2007 Chevrolet Cobalt 2.2L

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The ECM would not be bad, if the ECM was faulty it would have neither ignition spark  and Injector pulse. P0340 is just one code you have to deal there is also a near start condition this is the P0341 code, this would verify the camshaft signal. Try this clear the code for now at the MAF air duct use brake cleaner or carburetor cleaner no starting fluid. spray fluid in the throttle body, put the MAF air duct back start the engine, crank the engine a lot until start, when it start allow at least 4 minutes and see if P0341 set, P0340 you can also set this code due to hard to start situation.

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