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Q: Why the MegasquirtPNP Pro ECU blew all six ignition coils at first start

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The engine was taken out of the car and an overhaul (new crankshaft bearings, seals, piston rings and valve seals) was done . The engine was started on the ground and worked great. I converted the engine to single turbo (500 bhp). Engine still on the ground. I used the factory computer just to start the engine and it worked ok. I decided to install the MSPNP Pro ECU, followed the installation instructions. I tried starting the engine with the MSPNP Pro ECU hooked up. The engine backfired, did not start and a burst of hot air came through the intake manifold. I disconnected the MSPNP Pro ECU and reinstalled the factory computer but the engine would not start. On troubleshooting I found that all six ignition coils were damaged. I replaced the coils. The engine is starting again with the factory ECU. I would not attempt to use the MSPNP Pro ECU until I know what possibly went wrong ------ David

My car has 93000 miles.
My car has a manual transmission.

A: Hello. From what you describe it would appe...

Hello. From what you describe it would appear to me that the aftermarket ECU may have been the cause of the issue. I would verify that the aftermarket ECU was properly installed, as that is the only common denominator that all six of the coils have in common. This is more likely if the aftermarket ECU required any sort of wiring or harness modifications to fit. If not, it may be possible that the aftermarket ECU, or one of the ignition components or associated wiring has failed.

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