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304 Issues. Jeckle and Hyde

Walkers Bay

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So long yarn short.
I have a 304 in a VS Calais. Nice enough car, strong motor, 140km, HSV chip and knock sensor.
It starts, idles, does everything it should right up til the computer goes into closed loop.
Then it will not power away, splutters under heavy acceleration, you couldn't pass a car f you wanted.
Pop a lead off a sensor, trick it into open loop again and goes great again.
2 completely different motors in the same car.
I've tired...
Fuel pump and regulators (both)
Computer and Memcal
Tested the temp sensor (computer)
Tested TPS
Checked O2, even back probed and drove with it
Timing
Idle sensor, tick.
Changed the intake manifold gaskets.
Vacuum lines, checked and replaced as required.

What else could could it to fall so flat in the closed loop?
 

immortality

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Tried changing the O2 sensor?
 

immortality

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Where did you get the PCM/tune from? has it been altered?

What does it do if you do a full hard reset (disconnect the battery) so everything is back to running on stock tables?
 

Walkers Bay

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Where did you get the PCM/tune from? has it been altered?

What does it do if you do a full hard reset (disconnect the battery) so everything is back to running on stock tables?

It's a legit hsv computer with knock boards and sensor etc
I have a stock computer and tune too.
 

immortality

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Have you checked for fault codes?

You may need to log the car to see what is happening.

How old are the plugs, leads, rotor/cap and ignition coil?
 

Deuce

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@immortality
Do you think once up to temp it's detecting false knock and pulling ALL the timing?
WalkersBay, maybe disconnect knock sensor and drive
 

Walkers Bay

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Have you checked for fault codes?

You may need to log the car to see what is happening.

How old are the plugs, leads, rotor/cap and ignition coil?
Its logging a lean O2 sensor
The plugs have been done, the leads tested, the dizzy cap is new.
I'm leaning away from coil and ignition module because of how well it runs in open loop.
 
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