Noise from ecu when car is turned off

[clafrance]

I just had a JDM engine and transmission installed and I drove it home last night with no problems (aside from no headlights, probably unrelated to this though). This morning I started it up to make sure nothing else was wrong with it, and when I turned the car off I heard a buzzing noise comming from the ecu. I banged on the metal around the ecu and the noise changed from a clicking/buzzing to just buzzing. I didn't have time to do much else this morning but I was wondering if anyone had an idea as to what this could be? Should I start pricing out new ecu's? .... Prior to the engine install the ecu had never made any noise and all of the capacitors looked fine. Thanks.

 

[LightningGSX]

I think the JDM ecu's have a different pinout.So if you have the USDM ecu, I would guess something is not hooked up right.

 

[clafrance]

Would this cause it to make the noise only when the car is turned off?
I started it and it sounded fine, turned the car off and took the key out, and about 30 seconds later it started the "noise".

 

[LightningGSX]

Its possible, I couldn't really tell you for sure.

 

[BISHILVR]

ecu is prob on it's way out bro'

 

[LightningGSX]

Check the caps inside the ecu for leakage.

 

[Thunderskull]

Mine made the noise just before and then while it caught on fire. I'd replace it ASAP.

 

[clafrance]

I checked the ecu today and it's fine, my mechanic and I narrowed it down to a relay that sits next to the ecu. If I unplug it the car is fine, when plugged in and the car is off it buzzes and other celenoids under the hood do as well. We're thinking it's a bad ground but not sure where. The part number of the relay is E8T07071, does anyone have any experiance with this problem or any suggestions as to where to look? Thanks.

 

[clafrance]

I just got back from driving it around and it seems like it "sputters" when you get on the gas hard. Other than a little bit of idle surge (1100-1400rpms) the car appears to be running great. It's going back to my mechanic maybe monday, unless he calls me and it's something I can pick up at any parts store.