Possible bad ECM?

GUYFIXINGTRUCK..

MEMBER
2004 TOYOTA TACOMA
2.7L
4 CYL
4WD
MANUAL
230,000 MILES

Hi, I’m on here asking another question. My truck listed above had a misfire that was on one cylinder for a while. The engine would shake on acceleration and Check Engine light would blink, I swapped coils, looked at wiring nothing visibly wrong. New plugs, new coils, a lot of new sensors. Swapped fuel injectors as well, misfire still on same cylinder. And then all of a sudden randomly the misfire switches to another cylinder after all that time. Still couldn’t figure out what it was. Anyway, the truck sat for a while and went out to turn it on again just to get it running and then the fuel pump wouldn’t prime. Now I’m really thinking it’s the ECM, I mean I know they rarely go bad, but I think that may be what it is. Maybe that’s why the misfire moved and now there is no power to fuel pump. I don’t know, I don’t have a lot of knowledge, money or tools so simple explanations would be nice lol. Thanks God bless.

1 Reply

JACOBANDNICKOLAS

MECHANIC
108,320 POSTS

Hi,

When you try starting it, does the starter engage but the engine fails to start? Or does nothing happen?

If possible, record it cranking and upload it for me to hear.

Next, as far as the ECM, each coil has power once the key is on. A ground path is provided to fire the coil when the ECM deems it necessary. In most cases, it won't fix one and cause a different one to fail, but anything is possible.

You mentioned the vehicle sat for a while. Are you sure the battery is fully charged and in good condition?

Let me know.

Joe