Pulled out the ECM, replaced it and now fuel injection gets no power

Post by **jimmy57** » 30 Aug 2018, 07:02

If the ECM is not making contact then using the ECM remove/install tool will fix that and it should run. DO you know what fault codes the shop got? I m not aware of any emissions related faults caused by the ECM connections.

Post by **chrism** » 30 Aug 2018, 08:42

jimmy57 wrote: 30 Aug 2018, 07:02 I m not aware of any emissions related faults caused by the ECM connections.

Virtually all engine management sensors are wired to the ECM. So if the ECM is not properly connected there could be a multitude of sensors that are unable to communicate their readings back to the ECM. This can lead to all kinds of error codes.

For instance, I had some persistent fault codes pointing to a problem with the throttle module. Thorough cleaning didn't fix it. $350 for a new throttle module didn't fix it. But re-seating the ECM back into it's connector did fix it.

As these cars age and various harness connections become dirty/oxidized , I almost think that reseating the ECM is a first thing to do to eliminate that possibility. It's quick and free to do. Well, free except for the price of the latching tool which I've seen for as low as $15. The Haynes manual has a diagram showing how to DYI a homemade latching tool.

Post by **mrbrian200** » 30 Aug 2018, 09:41

jimmy57 wrote: 30 Aug 2018, 07:02 I'm not aware of any emissions related faults caused by the ECM connections.

The only ones I am aware of are O2s/fuel trims: O2 signal current may not 'punch through' minor oxidation on the contacts because current is so low, which is also why it's considered unwise to use standard 'bulb grease' on the ECU connector or O2s pigtail connectors. And the somewhat rare issue where arcing between a couple of the terminals at the TCM disturbs CAN communication.

Beyond that, issues with higher current circuits there probably indicates a flood or power washing under the bonnet without 'care'. The back of the ECU and TCM connectors (vehicle harness side) aren't weather pack sealed like most everything else under the hood. It's best not to point a sprayer/steam cleaner nozzle at the area directly around/underneath that box that holds those two computer modules.

PedroMotta4183 · Post by **PedroMotta4183** » 30 Oct 2018, 17:16

Solved issue:
Turns out the computer was not properly placed back in with the plastic tabs fully pressed in. Once I tried to set the computer again, and it fully set it, the car started right away.

inexus · Post by **inexus** » 29 Nov 2023, 00:06

Did you ever solve this problem and if you did how did you solve it.? My car has been sitting in the driveway for a whole week now. I pulled out the ECU and the TCM and when I put them back, the car has never started…!!!!!
It’s a real pain especially when you know that the car brought itself to where it is now.

dikidera · Post by **dikidera** » 29 Nov 2023, 01:21

inexus wrote: 29 Nov 2023, 00:06 Did you ever solve this problem and if you did how did you solve it.? My car has been sitting in the driveway for a whole week now. I pulled out the ECU and the TCM and when I put them back, the car has never started…!!!!!
It’s a real pain especially when you know that the car brought itself to where it is now.

Why yes, just read the post above yours. It literally says right there he had to re-seat them and fully pull up the tabs to lock the computers.