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This sounds like a lack of fuel and could be a lack of fuel pressure from the electrical pump at the tank.1st thing to try is to remove the fuel filler cap and then flick the ignition on whilst listening for the brief ‘buzz’ of the pump
If the connections to the pump are corroded or damaged then the pump could stop at any time or could not be running at full speed. Check that its relay switches in and out and the relay contacts are clean and bright – replace the relay if in any doubt and do the same for the fuse,Ideally measure the pressure at the injector rail (should usually be around 3Bar / 45psi +) and if this is low check the pump as described and also consider changing the fuel filter as if this partially blocked this too will reduce pressure.
You can also get this issue with contaminated fuel , if there’s water or dirt in the tank then either the petrol floats on top of the water or the filter sock on the pump is choked up – so if the other things check out then I’d consider pulling out the fuel pump and cleaning the filter sock
And one other thing to try is to loosen off the fuel filler cap, as there’s a 1 way valve built into the cap to let air into the tank and so prevent a vacuum from being created as the fuel leaves the tank to the engineIf this helps then replace the cap with a new item
if you're confident you still have fuel pressure when the issue occurs
then this could be a wiring issue as things tend to expand when hot and its possible a poor or partial electrical connection is being pushed apart on one of the major sensors so check the connection plug and wiring to the following;
Airflow meterCrank position sensorCam position sensorO2 sensorThrottle position sensor
unplug each in turn and use some switch / contact cleaner spray on the pins to ensure its all grease / dirt free
Also worth checking the connections to the fuel pump for the same reason - unplug each in turn and give them a good squirt of switch / contact cleaner - Not WD40
as you've already replaced sensors I feel its very likely an issue with the wiring loom and checking it over as I've mentioned is the 1st check and if this shows nothing I'd then disconnect the ECU and the sensors and use a meter to continuity check between the two
if you have a P170 code then its too lean and the next thing to check would be to check for exhaust leaks before the O2 sensor as if this has been experiencing an exhaust leak then it will have been running very rich as the sensor will see the extra air pulled in as fresh / lean fuelling and be adding fuel to compensate.
this can lead to catalyst failure as the extra fuel can re-light inside and melt the catalyst
The best way to find an exhaust leak is to run the engine from cold and feel around the exhaust joints with your bare hands - you'll have about 30 seconds before it all gets too hot and you should feel any escaping gas blowing over your fingers
if you haven't already then measure the fuel pressure to confirm that is at least 3 bar
glad to help
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