bcuformula

hi guys new to the forum just got a 99 formula auto 116k miles car has slp lid k&n magnaflow if i accel very lightly car runs good full accel runs great middle accel it chugs and lurches i have already changed plugs to factory ac delcos new wires fuel filter and o2 sensors no codes current maintains no vaccum leaks(did smoke test) 56 - 59 lbs of fuel pressure if i install my superchip program it won't get out of its own way

any suggestions would be great

thanks in advance

groundZ-28ERO

sounds like a tuning issue, mine surges bad in reverse if i lightly tap the throttle, also a tuning issue.

TTOP350

Since it has a K&N, clean the maf wires. Also check the fuel PSI while driving and issue is present.

westxwitesnake05

iTrader: (17)

is it throwing any codes? I had a similar symptoms with my car when I first got it.. it would studder and backfire, ect. turned out to be the crankshaft position sensor right above the starter.

Paul Bell

iTrader: (9)

bcu, welcome to LS1tech! SEARCH will be your best friend around here!

What's the condition of your MAF? Is the screen still in there? Have you changed the fuel filter?

Juiced99

I had the same issue...it's your MAF...unplug it and drive it..that will let you know if thats the problem or not. I ended up going with a 85mm off a Z-oh...and car feels like it gained 30hp.

bcuformula

cleaned it with maf cleaner didn't seem to help it maintained 56-59lbs at all rpms

bcuformula

thanks and not throwing any codes maf is clean and screen is there yes change fuel filter when i changed the plugs and wires