I had a bad fuel pump and replaced the pump with the fuel pump from a 2G DSM gsx and also replaced the fuel filter.

I finally get the car started (stock S5 vert) and put together and attempt to take it for a drive and as soon as i put it in gear (its auto) it starts sputtering and when i try to give it some gas it dies, if i don't give it gas it'll coast for a bit while sputtering......did it a few times. (i'm guessing the dsm fuel pump isn't putting out enough fuel and i'm wondering about putting in a walbro 255)

Car also starts to rev to 3k at cold start then after a min or so drops down to 1.5k, the idle screw is tightened all the way (clockwise), if i turn it counterclockwise the rpms go up.

I also have been getting white smoke but it's barely noticeable unless revving
car also has the left muffler blown out.....i'm guessing the cats are blown (probably gonna go straight pipe)

also for the small "test" drive i had i got this weird clunking noise coming from the rear end

 

Get the correct fuel pump. You don't need one that pumps more than stock, so find a used one for sale in the classifieds. If the S4 and S5 fuel pumps are the same, I have one for sale.

For the high idle, set the TPS correctly, then set the idle. There are numerous variables that affect idle, so read up in the FSM (available online).

White smoke is generally indicative of blown coolant seals in your motor. Coolant leaks into the combustion chamber, and burns white. Fixed with a full motor rebuild.

Rear end clunking could be several things; the differential's front mount most likely.

 

ok i put in a 255 and i'm still getting a dead car a few moments after i put it in gear

on the white smoke issue i unhooked the cat and didn't really get white smoke anymore but i'm gonna wait it out on that issue

the rear end clunking was a few loose wheel lugs


anyone know how to get my idle down.....i'm idling at about 1.75k to 2k....i've been trying to find the tps and how to adjust it and i think i found it....while i'm checking please chime in on what else to do to get my idle lower just in case

 

ok the high idle was due to a throttle cable not sitting correctly.....

I adjusted the tps using the light bulb method (correct me if i'm wrong but can you only adjust no throttle and not WOT with that method, all i adjusted was no throttle)

car still dies whenever i give it gas in gear.....not as bad now though (i can actually just coast it as long as i want but as soon as i start trying to give it gas it normally dies) please help peeps, any ideas, thoughts or guesses on what i might need to check?

 

i would just take it in to a mechanic to get tuned but i don't know of any in the area