Engine wont fire.

[Phillbert]

I swapped motor n box in the ute, got it going
Bit rough to start but when it started it's fine. Idles correct and rev's great....

I disconnected the battery lead to reset computer so i could reset the fault codes and tune the TB (start car, rev for 20sec at 2000rpm)

I put the battery lead back on and now it won't start, I didn't change anything just took the battery lead off for 1 min and back on.

Light come on, car cranks but no start.
I got someone to put some aerostart in the TB when cranking and it didn't start.
It was low on fuel so i put another $20 in it so not that problem
Can hear the fuel pump doing it's thing
Even changed the old memcal back over to see if that was an issue

Where do i go next?
No i have checked spark yet, will do tomorrow as i was over it today...

 

[The_Captain_1971]

Spark check for sure mate; that will either confirm or eliminate a few things!

Battery? Dizzy?

keep us posted on what you do

 

[Trevor loves holden.]

Open relay or a fried fuse.

 

[BlackVXGTS]

Have you checked your error codes? Which battery lead did you disconnect - positive or negative (earth)?
https://forums.justcommodores.com.a...nd-comprehensive-dtc-error-codes-list.179140/

 

[Phillbert]

Took the Poss (+) off
Checked codes again and had 12 and 23
Code 23 - Mass Air Temp Sensor (MAT) high voltage

 

[BlackVXGTS]

Code 23 is Intake Air Temperature Sensor (IAT) Signal Voltage High.

You should have disconnected the negative battery terminal (earth). Your car may have received an electrical spike that damaged some component(s) as Trevor loves holden suggested in his post. Code 23 should not stop your car from starting.

 

[Phillbert]

Replaced the Start Relay and got it going, ran it for about 10 mins turned it off, when to start again and same thing blown start relay.

 

[Lex]

Check the wiring to the relay.

 

[Phillbert]

ok this is getting weird.
Changed the Starter Relay it started for about 10 mins till i shut it off with key.
It won't start again, thought it was the same thing but not so, changed the Starter Relay again but no go this time. Back to same thing...
I put the old Relays back into the other ute i have and it fired up first go so it's not the relay.

Checked the wiring and it seems ok from what i can see.

 

[Phillbert]

oh forgot to add i checked the error codes and only 12 came up