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Starboard engine won’t fire
I have a Cobalt 343 with twin 496 HO’s. Last fall I damaged a push rod on my starboard engine, still started and idled fine when we pulled it out to have it rebuilt. Just had the engine reinstalled last week and in won’t start, just cranks with a poor fire about every 20th revolution, or so. We’ve swapped the crank sensor, cam sensor and pcm with the running port engine and still have the same response and we have great fuel pressure. Any thoughts?
*also, I’m told the left vs right engine pcm’s might be different? -Any help would be appreciated... -Currently no active faults are shown while connected to mercury diagnostics... |
Timing?
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What's the motor serial number?
Reason for the rebuild? When key is turned ON, does the fuel pump run? Do you hear it beep? When cranking can you see the Tach show 300 rpm or so? |
Originally Posted by AllDodge
(Post 4791526)
What's the motor serial number?
Reason for the rebuild? When key is turned ON, does the fuel pump run? Do you hear it beep? When cranking can you see the Tach show 300 rpm or so? Damaged push rod Yes - and I have >40 psi of fuel pressure when turning key to on position Yes, we have rpm |
Something is not making connection
RPM shows so CPS is connected Fuel pump turns ON so MPR and FPR is working Coil harness to engine harness Injector harness to engine harness Fuse to fuel injector harness From manual 33 The normal resistance values for these sensors at 21 degrees C (70 degrees F) are: Camshaft Position Sensor - A to B 24.04 mohms and B to C 24.05 mohms Crankshaft Position Sensor - A to B 23.2 mohms and B to C 23.21 mohms. With software prior to level 091, a malfunction of the crankshaft position sensor or the camshaft position sensor will not set a fault.With level 091 software, if the camshaft position sensor is bad and does not send a signal to the PCM, the engine will backfire and not start. |
Did you replace the timing chain? If so, what did you use?
Also, who did the work, you or a shop? |
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