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08/09 ECU ground location

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In the pics below, is that the ground for the ECU? I've seen a few vids on other similar cars like WRX's where the ECU is actually grounded to the intake bolts. I can't find anything on any of the intake bolts or the TMIC bracket.


Reason I'm doing this is I haven't logged with my Accessport in years, and wanted to check up on things before I do a couple more mods and get a protune. The issue I'm having is every single time under load and WOT the Accessport stops logging and momentarily looses connection in the upper 3000RPM range. Speaking with COBB, and doing some research the first suggestion is to check and clean up all grounds. Cleaned up the battery terminals, the ground to the drivers side shock tower, and the head to frame grounds and the last one suggested was the ECU. Couldn't seem to find any pics anywhere. Cleaning these up is step 1 to see if it works, next is a new battery (I'm due anyway) and after that I'd like to run fresh grounds like I've seen mentioned in a few of the DIY threads. If there is still no improvement I'm going to try a different set of plugs, I forget what's in the car now but saw that somewhere as another suggestion to try. Figured one thing at a time to see if there is any improvement.





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There should be 2 braided ground straps on the underside of the engine to the body, one on either side. Since they are not insulated they tend to disintegrate.


Mine had disintegrated and would occasionally throw a weird "Drive Mode Changed" or some such on the dash till I fixed that.

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The grounds are right under the throttle coupler, firewall side on the tgv (drivers). When I removed all of that I extended a ground cable to the starter ground.


When I had that issue with my accessport, the pins were loose on the OBD-II connector.

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  • 2 weeks later...
Thanks for the pics Max Capacity. Got me into the general area for what I think is the ECU ground. My car being an 09, it has all the air pump junk in the way so the grounds in your very first pic are not in the same spot. I have some bracket that goes around the side of the intake manifold/injectors and there seems to be one ground towards the rear of that bracket, really buried behind some hoses. Haven't gotten a chance to run all the new wires yet, but realized if I monitor voltage when WOT it dips to 13.5 then cuts out after that. So maybe it drops even further. I'm slow and lazy doing things but I'll post back when I get around to trying a few things and see if there is any improvement.
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IIRC, the engine grounds changed in 07 with the D25 heads/air pump setup. My 05 had the same two-ground manifold setup in the pics Max Capacity provided, but the 07 motor I swapped in had only one ground off the manifold in the same general area. Pretty sure that's the only ground from the manifold wiring harness




Is it a v2 or v3 accessport? Thought I remembered my friend's v2 acting similarly before it ended up kicking the bucket

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