bad cutt

iTrader: (5)

i have a 03 sierra with a turbo on it. it is a frt mount turbo. I have had it done for a couple years. i run about 10 lbs. anytime i mat wot it wants to surge the boost stays consant at about 10- 11 psi. I have a water meth injection kit on it. I run washer fluid in it and previously this surging wasnt a problem so i doubt that is it. it pulls great and runs perfect until u get to wot. any ideas?

MikeGyver

iTrader: (5)

You're losing your fuel pump.

bad cutt

iTrader: (5)

quite possibly ill put a gauge on it tomorrow and check pressure. thanks

blazinblue

iTrader: (15)

hows the afr??

bad cutt

iTrader: (5)

havent checked the afr yet my genesis is at work in my toolbox and it just started this morning

bad cutt

iTrader: (5)

its not the fuel pump pressure stays constant at right around 60

MikeGyver

iTrader: (5)

At the same time it is surging it stays 60? Anyway, it should not stay steady. It should vary with vacuum and go up with boost on a return-type system.

Gadgetized

iTrader: (9)

Can you explain the surging better? Do you mean the engine is surging, or turbo surging? Does the turbine spin freely, or is there wobble in it? Are the wastegate and BOV working properly? It could be the MAF, but would need more info.

bad cutt

iTrader: (5)

Fuel pressure actually does go up with boost. i should have siad it never goes below 60. there is no maf i have a 3 bar. turbo spins freely. it is not the turbo surging it is the truck. at about 90 at wot it starts surging kindof like its pulling hard and then its not. almost like i am letting off the throttle slightly. the boost stays at about 10 psi and doesnt fluctuate. it only seems to happen after i am at wot for a few seconds. its hard to stay at wot for very long if i stay at wot for more than a few seconds i am running north of 120. maybe i should hold it in second and see what it does.

MikeGyver

iTrader: (5)

Did this start with the alcohol injection system?