surging while crusing

[gofast63]

I can seem to figure this out. I've took care of all of my boost leaks and checks plug and gaped them to .28, cleaned fuel injectors, its a rebuilt engine, I'm now running my 550cc injectors and had this same problem with the 450cc. Coil packs new, rebuilt throttle body, rebuilt turbo, replaced seal on biss screw. My wideband hits 16 while crusing when it surges.

 

[91tsiawdtalon4g63]

16 isn't bad when you're cruising. You're saving gas when it's a little lean on cruise. Explain more on your surging if you could please

 

[IdleSurge]

More than likely you are hitting fuel cut. Check your idle position switch and tps sensor. Your ecu might be thinking that the car is idling when you are cruising and it will try to lower the rpms and one way it can do this is by cutting fuel hence why you are leaning out.

Does the car surge at all during idle?

try cruising at speeds below 1200 rpm and above 1500 rpm. Report back if it only surges and leans out at speeds above 1200 or 1500 rpm?

Does it surge if your throttle is at 20% or only surges if the throttle is at 2%-8% ?

16:1 afr is not good when cruising aim for a range of 14.4-15.2