Revelation Z28

iTrader: (10)

ive noticed that when i back out of the driveway, the rpm will dip and the engine will sputter a little until i get going. when when i do coasting at 5mph, itll buck. and when i need to accellerate, sometimes ill only be getting minimal power, but itll also feel like it doesnt know what the throttle position is in. a few times i was in 1st and 4th and i wasnt getting any power to the rear wheels which told me its a slipping clutch, but that checked out ok. also, ive noticed a change in how the car runs when the switch from open loop to closed loop happens, the engine sounds like it has a small cam and the body shakes. also it backfires alot during engine braking. and another thing i noticed is it doesnt keep that 1500rpm idle until i come to a complete stop. itll go down to its 1000rpm idle speed..

i have recently put in:

walbro 255 from summit with a length of FI hose to connect to the fittings on the assembly.
GM AC delco optispark
AC delco plugs
and OEM plug wires. (i took the taylor OTVC kit off)

now im thinking the pump may be getting too hot because i dont have the racetronix hotwire kit.

or it could be the coil since its 2 1/2 years old.

or a vacuum leak. but i cant hear any hissing.

so i ask of your help on this guys

Fixxer99TA

iTrader: (5)

I want to say O2 sensors, considering the change... How old are those?

Revelation Z28

iTrader: (10)

like 3 months old

sweet-94z28

iTrader: (30)

Have you ever cleaned your MAF? It makes a difference sometimes, but I am also gonna lean toward o2's. What brand did you use?

Revelation Z28

iTrader: (10)

just cleaned it.

bosch o2s both sets.

the first set didnt give me any problems, it may be these.

Fixxer99TA

iTrader: (5)

I would think its pretty unlikely that it would be your opti, considering its an AC piece. But it has happened before. Those are opti symptoms also....

When mine was going it idled real crazy (800-1200) and did the same thing (no power sometimes, backfiring the whole bit).

Revelation Z28

iTrader: (10)

it has that 'not getting enough fuel' feeling when i go wot.

it doesnt backfire when accellerating, only sometimes ill get light pops on idle or engine braking.