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Discussion Starter · #1 ·
I'm really hoping someone can help me with an issue I am having with my WRX after a full engine rebuild.

So my car has been off the road for almost 2 years while I underwent a full engine rebuild. I finally got it all back together and went to fire her up and the car cranked, but did not start.

I had a local technician come check it out, and the first problem we noticed was that the fuel pump did not turn on when the ignition was in the on position. I had replaced the fuel pump to a DW unit and swapped it back with the oem one as well just to make sure it wasn't the fuel pump. They are charging me 100bucks/hour and after 10 hours of checking each pinout of the ECU they told me some of them were having wrong readings and that they want to swap out the entire dash harness which is gonna cost me thousands in labor. They think a rodent might've chewed through some wires while my car sat for 2 years, but I think it's kinda unlikely. I want to troubleshoot a bit further before I go with this option.

There's 2 things that I initially might think is an issue but the car is at the shop right now so I don't have access to the car but next time I visit I want to try out some things before I decide that the harness needs to be replaced.

First, I have installed new composite TGVs and in the installation notes it said the ground needs to be relocated. My technician told me this shouldn't be the issue since there are bolts that run through both the manifold and the blocks so it should still be grounded, but I had painted my manifold so it is most likely a grounding issue that I'm having. I was confused as to how to relocate the ground.

Do you run a wire from the ground on the manifold to the engine block, from the manifold to the chassis, or do you move the grounding point completely from the manifold to somewhere else? If someone has any idea on how to properly ground your car after a TGV delete it would be appreciated.

Second culprit is that my car was broken into while it was sitting and had my radio stolen. The thieves cut a bunch of wires to get the radio out but I don't really see anything in there that could be causing an issue. I will try to get a picture next time and make sure that the ground wire, which was one of the lines that was cut, isn't touching something.

I know my issue is kind of vague, I'll try to get a more clear idea of what the issues are the next time I'm down at the shop, but first and foremost I want to make sure my car is grounded properly with the composite TGVs in place if someone could give me some advice.

To clear up what I'm asking, there are 2 grounding points on the manifold. Shown in the pictures B and D. I am not sure if I need to run wires from those points to the block, or to a new point on the chassis. If anyone knows and could help me out it'd be seriously appreciated.



 

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Your grounding worries has no bearing on the fact that your car won't start. You are correct to want to properly ground it, but it has no effect on starting. You can run proper grounding wire to EITHER the block or the chassis.

Rodents chewing wires is certainly possible (I have seen it happen several times) but if they had, you'd likely find evidence in the cabin of them chewing on other things and you'd see poop and shredded stuff elsewhere.

Of course no one here can tell you what the problem is, but since you had a total rebuild and mentioned the shop telling you wrong readings on ECU pins, It's a pretty good bet something isn't connected up properly in the wiring as a result of the build............................(and its not the TGV grounds)
 

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Discussion Starter · #3 ·
Your grounding worries has no bearing on the fact that your car won't start. You are correct to want to properly ground it, but it has no effect on starting. You can run proper grounding wire to EITHER the block or the chassis.

Rodents chewing wires is certainly possible (I have seen it happen several times) but if they had, you'd likely find evidence in the cabin of them chewing on other things and you'd see poop and shredded stuff elsewhere.

Of course no one here can tell you what the problem is, but since you had a total rebuild and mentioned the shop telling you wrong readings on ECU pins, It's a pretty good bet something isn't connected up properly in the wiring as a result of the build............................(and its not the TGV grounds)
Thanks for your advice, I just thought that an improper ground would definitely cause some electrical issue because a bunch of sensors located on the engine block like the crank, cam, and knock sensors would require a proper ground to function properly. As mentioned, going with the entire harness swap is gonna cost me thousands and the build has already exhausted me of my funds, so I'm looking for anything that might help me solve or crack down the issue before I drop the money on it. My biggest fear is what if I do the whole harness swap and the issue still persists... :cry:

I'm so close to finishing the build after 2 years and to get the news that the car basically needs to be taken apart again has me in tears basically.
 

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Discussion Starter · #4 ·
Your grounding worries has no bearing on the fact that your car won't start. You are correct to want to properly ground it, but it has no effect on starting. You can run proper grounding wire to EITHER the block or the chassis.

Rodents chewing wires is certainly possible (I have seen it happen several times) but if they had, you'd likely find evidence in the cabin of them chewing on other things and you'd see poop and shredded stuff elsewhere.

Of course no one here can tell you what the problem is, but since you had a total rebuild and mentioned the shop telling you wrong readings on ECU pins, It's a pretty good bet something isn't connected up properly in the wiring as a result of the build............................(and its not the TGV grounds)
So it did turn out that all it needed was a grounding wire to be run from the manifold to the chassis... The manifold had no ground because the composite TGVs and the manifold had voltage on it due to it, causing none of the sensors on it to function properly as well as the fuel pump. All the ECU pinout turned out normal after proper ground as well. Car starts up fine now! :)
 

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Yup.. if you're not getting good readings from your crank position sensor (among other things), the car won't start.
 
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