Engine Weird thing happened tonight

Just a quick update my ecu is repaired and on its way back to me from EcuExchange here is what they said..


The repair details below are generalized, if your computer has any short circuits or we suspect any wiring should be checked before reinstallation we will put specific details above.

Your computer will return ship ASAP, we do clean and seal the board for moisture intrusion as well as clean the outside.

The power supply in your computer was defective due to age, causing distortion on the system voltages. We replaced the power supply along with the capacitors and voltage regulators. which are common to fail and this will prevent future defects.

We also Replaced a couple other circuits which are known to fail while we were in there to prevent future failures.

If you have any questions, please feel free to ask. We're always happy to help.

Is it ok to put my Bama chip in when I get it back?
Got my Ecu back hooked it back up put the negative terminal on the battery mine is in the trunk. Tried to start it still just cranks no start .


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You need to do try some things....

Ground the battery really good to the unibody then find the two ground wires going to pins #40 and 60 plus the ECU relay ground wire ...

Those wires need to be cleaned up and grounded good to the unibody too but best place is to route those negatives direct to the battery as the battery is a Cathode that absorbs r/f noise.....

For the negative path in a trunk mounted battery I do whats very unheard of as its not too cost effective but there are cheaper ways that work just as good using this stuff.... ....


For my ground strap I use a roll of 1/8" thick soft copper flashing and use a brake and a sheetmetal trimmer and I trimmed off a 8ft long piece thats 2" wide then I made two overlapping bends by folding it back against itself then soldered the joint...

After that I drilled 40 holes in it and then I took a grinder and I grinded away the paint on the inside floor of the vehicle 1" then I drilled and used copper rivets to rivet the copper strip to the body all the way to the firewall then I made a copper grounding lug that gets attached with a thick braided grounding strap to the engine block and another 2 gauge cable to the core support area...

I also take some paint then some undercoating to cover over the area then I put back the rug and the passenger seat if its a full interior vehicle...


I even made special grounding strips for my regular batteries that filter EMI radiation aswell as r/f interference..

If anyone knows physics and such you'll know that it takes destructive methods to destroy EMI radiation until it was discovered in 2017 that Ansitropic Crystals absorbs EMI radiation naturally....LOL.....Oh and for those that dont know the alternator produces EMI radiation when it produces voltage....



Some will say that solid copper grounding is not needed and plain old cable direct to the unibody is ok but you need a double run of 0 gauge to ground an automobiles electric system better than solid copper or the steel unibody when the battery is further than it is from the factory as length adds resistance so youll need a battery that delivers atleast 1000 cold cranking amps and 850 cranking amps and a ground that bridges the power lightning quick and stong as an ox..........

I would also run a 0 gauge positive wire and if you dont have a mini starter mount the starter relay as close to the starter mounted to the transmission or frame....

I also run a 4 gauge wire from the battery to the two column switch power feed wires and add a 4 gauge wire to the 10 gauge ECU relay power wire too...

That much extra distance will cause all sorts of voltage issues...

In my Lamborghini Diablo kitcar I made the whole firewall out of a 1/8" 4' x 8' sheet of copper too with a copper busbar from the battery to the firewall...........It wasnt easy but it was well worth it as I dont get any of the power issues the other members get with slow lazy power windows or slow cranking highly laborous hot start issues or dim lighting on the instrumentation panels and most overall;-No Stacked-up grounds all on a single screw because fiberglass is a very poor electrical conductor ...LOL
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Interesting, but not necessary.
New vehicles typically have one negative ground cable from the battery to the frame with a junction that goes to the engine block.
Not a single ECU, (Electronic Control Unit) be that the Engine Control, Trans Control, Body Control, Chassis Control ect ect have ground wires that attach directly to the battery negative post. Some cars have over 50 ECU's and not a single ground wire goes straight to the battery.
You will see lots of ground wires attached to the frame or body.
Also on new cars that have the battery mounted in the trunk, or behind or under the passenger seat will have a CCA rating in the mid 700's or so. With the massive amounts of electronics on these vehicles that seems to be completely sufficient to operate the vehicle. Low voltage on a new vehicle can cause all kinds of problems, yet the factory does not jump through all of hoops listed above.
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If the ecu is grounded directly to the battery at the post and the cables are accidentally reversed or a connection across the posts occurs it can turn the ecu to toast, same with 'stacking' grounds to more than one circuit to a single spot, bad idea, I'm not a expert in automotive electrical stuff just advice given to me by persons smarter than me.
I'm not disagreeing with the above posts, some are more technical than the average hot rodder can comprehend
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