Message So I started noticing on my wideband that I would go lean under boost and began investigating. I hooked up an in line fuel pressure gauge that I could read from the cabin and monitored fuel pressure under boost. During normal driving (below 0 psi) the car is fine and keeps the proper 44 psi pressure differential. Once the Z goes to 0 psi or into boost fuel pressure begins trailing off causing the lean condition. For the intial accelerations under boost I wont notice this condition but after a few boosts or an hour or so of driving it appears so I'm assuming it is heat or workload related. Is it a pretty safe bet that the fuel pump is failing or could the fuel pump controller actually be a culprit also? Also what is the best option for obtaining a pump or controller? New OEM or verified working used? Thanks for the advice.
