Car starts and runs fine until you really get into it in 2nd or 3rd gear, especially having this problem at the track.

Car ran fine last year with no issues on a version 1 aem. Changed that out this year for a stock ecu. Had the stock ecu I bought in the car for a while without really beating on it so I wasn't aware of any issues.

Take the car to the track starts breaking up like crazy. Next day I change out the ignition system, injectors and ecu. Car starts on my stock ecu, throw my friends ecu in the car with my tune and the car won't start at all and throws crank sensor code.

That code would makes the breaking up make sense sort of but with the sensor as bad as my friends ecu thinks the car shouldn't even run... a bad crank sensor should also stop your motor from getting spark or fuel..

How is my ecu picking up enough signal to run and drive the car decently but another ecu won't even start the car up because of a bad crank sensor... And my friends ecu is a working ecu that was pulled out of a running car.

Anyone ever experience anything like this?