Hello all. I recently flashed my ECU with a tune from elevate/autotech. When accelerating hard, it feels fine until about 2k RPM and then all of a sudden experiences sporadic and semi violent powerloss. I highly doubt its the tune as I'm sure autotech has done MANY tunes. Other possibilities may be the need for colder plugs, bad TCV, old ignition coils (although I doubt this). Has anyone else heard of or experienced this? Cheers!

 

A failing fuel pressure sensor will act like that. But you should get a check engine light with a code for bad fuel pressure sensor.

Any knocking? You might also be getting some timing pulled if the ECU detects knocking.

 

No codes were thrown... what does knocking sound/feel like? I've never experienced it. The car does shudder and kick in randomly in rapid intervals.

 

Just went out for a romp to see how it behaved... It seems as though every time boost goes past 10psi it goes all wonky. That being said, it feels like I'm not getting enough fuel. But if that was the case I figure I'd be seeing codes.

 

Your tune may have the codes turned off. That's a wag only. I do not know what they due to the tune.

If it goes lean above 10 psi then it could very well bog. This is dangerous territory too. Like melting pistons from temp spikes.

Knocking you may or may not hear. In the old 80's cars without knock sensors you could hear knock clear as day. It's a metallic rattling sound from the engine compartment with the car under heavy acceleration. Usually premium fuel would fix it. You running premium? You may have bought a tune which requires premium to stop knocking. Now modern cars with knock sensors will pull timing when they detect knock. Some engines pull a bunch of timing which causes the car to fall on its face. Others it's a gentle loss of power until the knocking is no longer detected. The rate at which degrees of timing are pulled can be altered in the tune. An aggressive tune may dictate an aggressive knock retard rate to make sure no engine damage is done.