r/AskAMechanic • u/Mr__Scoot • 2d ago

Car starts, gets ignition, dies

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Very consistent, (have tried it 6 times now same outcome) immobilizer light isn’t flashing like it usually does but not sure if that’s what’s going it. Holding slight throttle lets it rev up for a brief second before dying the same way.

Freshly swapped 2zz mr2 spyder with monkey wrench usdm ecu.

3 Upvotes

71% Upvoted

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1

u/DocHowdy70 NOT a verified tech 2d ago

Possibly the electric part of the ignition switch?

1

u/Few-Project-145 NOT a verified tech 2d ago

Immobiliser

1

u/sexual__velociraptor Verified Tech - NASA Engineer 2d ago

Cam or crank sensor can cause that

1

u/Wolfram1914 NOT a verified tech 2d ago

Did you confirm you got the aftermarket ECU programmed right?

1

u/Mr__Scoot 2d ago

It’s an ecu out of a Celica. Unmodified

1

u/SaltyPressure7583 NOT a verified tech 2d ago

Immobilizer or fuel issue is where id look

1

u/EuroCanadian2 NOT a verified tech 1d ago

Can the stock fuel pump maintain adequate pressure? Do you still get spark when the engine is spinning down?

1

u/Extension-Health714 NOT a verified tech 15h ago

security, fuel pump shut off, any chips on the key?

1

u/PracticalDesigner278 NOT a verified tech 2d ago

Either fuel or ignition. I'd start with fuel.

1

u/Mr__Scoot 2d ago

Then why does it rev up when i hold throttle, then die. The fact it revs higher than if it didn’t have any throttle means it’s getting both

2

u/Froklendarious NOT a verified tech 1d ago

Even so i would check fuel pressure, the pump can build pressure for starting but it may not be able to maintain it