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Having issues starting the car quick stemmed from a change of battery. 


I changed the battery and stupidly forgot to secure the terminals to the battery. 


Was driving along and saw the battery light flashing. Releasing I may not have secured the terminals enough I switch the car off whilst rolling and tried to turn on again. There was no power. Tried to clutch start so I can inspect on arrival at my destination and it wouldn't start. I pulled over to connect the battery turned turned the key and the wippers started going off on their own really fast. It was like a surge of power. From there the instrument cluster wasn't functioning and the car wouldn't start. All lights, fan, starter motor work but wont fire up. I cant hear the fuel pump. The Efi main relay is clicking on key turn.


There is 12v going to the ECU plug (mega squirt diy).

Car was running great before this. I did notice the Can positioning sensor was loose. I tightened up but no start and no dash lights.


Any ideal?



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Check all your fuses

Check your ground strap, bad grounds can cause weird stuff to happen.


But yeah, if the battery/terminals were loose something may have shifted while driving and shorted, which would probably pop a fuse etc.

Checked all the fuses and they are all good in fuses box under dash and in engine bay.

Are there any hidden?


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anastasic81 wrote:It was like a surge of power.

(mega squirt diy).

I don't like this combination......

It's also possible you had a fault before you replaced the battery. This may have made the old battery seem weaker than it was. Installing a new battery could have made the situation worse too.

Have you checked the earth straps yet? On an NA they are from PPF to chassis near the rear axle, from engine to firewall near the exhaust manifold, from the loom to the front of the intake manifold and the battery earth strap from battery to body. I think they're the same on an NB but I'm not completely sure. Things can go pretty feral when that first one - PPF to chassis - is loose.

Edit: also forgot to ask how well you inspected and cleaned the battery terminal clamps before eventually tightening them up.

I'll check the earths. The thing I don't understand, it kicks over strong and the lights, power windows don't seem like the are straining.

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The first thing I thought, and what I keep thinking, is maybe the map in the Megasquirt has been wiped clean. The first thing I'd do is check it's still programmed correctly.

That cant happen.

I just wanted to plug Alex from BARTUNE who built the mega squirt ECU. It's been over a year since I bought the unit from him. In reaching to see if he can help he has been extremely helpful. Although my issue is still there he has provided a fair bit for me to look at!

Not sure if he is still building ECUs but his service is excellent and much appreciated in times like these.





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