Engine starts and runs great when cold, after warming up the engine stumbles and dies

This is usually caused by a bad ecm. As the engine warms up, the ecu gets heat soak and will start to fail.

How long will shipping take?

Standard orders that are placed will ship out next business day. If you want overnight shipping please select in the drop down menu on the check out page.

Where do i ship my core ecu back?

Return label will be placed in the package.

Gt40Marine

5210 Rainier Dr e

Bonney Lake, Wa 98391

A list of possible symptoms

Low fuel pressure
Heat Soak
Bogging down after reaching running temp
No spark
Fuel pump not priming
Boat has been jump-started on reverse polarity
Engine Computer water or burn damage
Injection pulse or fuel pump loss of power
Erratic engine idle
Bad running condition
Bad fuel economy

Mark Hillman

Client Review

"We (N3 Boatworks) ordered an ECM from Gt40Marine last summer. No issues. Customer service on point".

Adam Barnhart

N3 Boatworks

"We (N3 Boatworks) ordered an ECM from Gt40Marine last summer. No issues. Customer service on point".

Riley Jones

Client Review

"We (N3 Boatworks) ordered an ECM from Gt40Marine last summer. No issues. Customer service on point".

"What Others are Saying"

Symptoms of a Faulty ECU

Low fuel pressure

Heat soak

Bogging down after reaching running temp

No spark

Fuel pump not priming

Injection pulse or fuel pump loss of power

Erratic engine idle

Bad running condition

Bad fuel economy

Boat has been jump-started on reverse polarity Ecu has water or burn damage

Frequently Asked Questions