sr20det fuel problem??

[mostdopes13]

ok slowly over the past week the car has been boggin out while just cruising at 45 or any speed really but it wasn't to bad. the last couple days it got horrible even undriveable almost so i parked it. it will build revs just slowly and sputters a ton.
if i first start up the car for about the first minute or so it does fine and revs up perfect but after starts to get a rough idle..

i replaced the fuel filter buit i figured it wouldnt help which it didn't.
i'm goin to buy a fuel pump tonight for it but any other ideas on what it could be?

also if i give it full throttle it handles itself better than just partial. it still sputters a little but under full boost it isnt to bad. i know it's not a boost leak because and i'm almost positive its not a vac leak./

s13 redtop with t25
motor is all stock with sohc maf

[mostdopes13]

anyone got any ideas

[s13 drifta]

Are you running a stock fuel pump? If you are I would upgrade to atleast a walbro 255lph.

[mostdopes13]

Are you running a stock fuel pump? If you are I would upgrade to atleast a walbro 255lph.
im not sure if it's stock or not but im getting a walbro tonight for a good price so i hope thats it. i just dont understand why it would run good the first couple minutes then slowly get worse

[mostdopes13]

put a new fuel pump in and its still doing it... anyone got any ideas on what to try next?

[Mikester]

Check for vac/boost leaks.

Check your plugs. If you ever used octane booster, they are cooked- I promise.

[mostdopes13]

Check for vac/boost leaks.

Check your plugs. If you ever used octane booster, they are cooked- I promise.

got the car a few weeks ago so im not sure if po did but i'm positive theyre no vac or boost leaks

[mostdopes13]

i have an exhaust leak on the downpipe could this cause the 02 sensor to be reading wrong and making it sputter?

[Dborne]

I had the same problem, mine was running on three cylinders. I believe it to be a sticky injector, I ran injector cleaner through and it cleared up for the most part.

[mostdopes13]

I had the same problem, mine was running on three cylinders. I believe it to be a sticky injector, I ran injector cleaner through and it cleared up for the most part.

word i'll buy some today and give that a shot tonight. i have a feeling it isn't an injector tho

[mostdopes13]

replaced spark plugs and car ran fine for about 10 inutes at idle no problem. turned it off then back on about 10 min later and started to cut up again. really bad right when the turbo starts to spool but in full boost its fine. sprayed carb cleaner everywhere to find vac leaks but found nopthing.. i think it's probably just a boost leak? after i drove it around teh neighborhood tho it went back to idleing really rough. any ideas?

if it is a boost leak i don't understand why it would do it at idle

[mostdopes13]

in case anyone has a similar problem it turned out to be a boost leak and bad spark plugs. inlet on the manifold has a stud broken and so one bolt was holding it in only so the gap got increasingly bigger and slowly made it run worse and worse.