All stock, acceleration issues

[USA_DD_S2]

Ladies and Gents,

Been trying to work through a sudden loss of acceleration on the S2 R33 GTS25T over 3000rpm or so at WOT. I can baby it up to about 4500rpm but it loses its go about there also. 99% sure my oem cat is done.

OEM fuel filter, OEM Coils (x6), serious AAC cleaning were done chasing a solution. OEM MAF, NGK plugs pregapped to 1.1, coil pack harness were previously done. Cleaning my throttle body in the morning, and giving my ECU a reset. I can hear a ticking/whoosy whoosy noise going through my cat at idle. Plan on popping that off tomorrow too and checking it out. Pretty sure its gone.

My big question is whats the OEM cat cell count? I dont have the funds to jump to a tuner/tune and cat at the moment. Figure a Venom 400 cell should get me running well for a bit until I get some supporting mods and a tune. Any suggestions? Again, car is entirely stock, unless you count some aftermarket brake pads 😅 Many thanks.

Edited December 19, 2021 by USA_DD_S2

[Ben C34]

Any cat / no cat will work.

 

Have you checked for a boost leak?

[USA_DD_S2]

On 12/18/2021 at 9:24 PM, Ben C34 said:

Any cat / no cat will work.

 

Have you checked for a boost leak?

I havent run a proper boost leak test. Im checking things as I go and havent found one yet. 
Any cat? I dont want to run a test pipe without a tune so I figure the more cells the better. Also looks like S13/14 cats/pipes will bolt up too. I seem to have more options grabbing an S chassis one (Im from the US)

[USA_DD_S2]

On 12/18/2021 at 9:24 PM, Ben C34 said:

Any cat / no cat will work.

 

Have you checked for a boost leak?

One thing I forgot to mention is its having a tough time starting up. I dont remember what symptoms I had when I clogged a cat a decade ago on a Z33 but I dont remember starting problems being one. Either way, it sounds like I need a cat

[GTSBoy]

It's unlikely to be the cat.

Literally everything else is more likely. Fuel pump dying is far more likely.

[USA_DD_S2]

On 12/18/2021 at 10:44 PM, GTSBoy said:

It's unlikely to be the cat.

Literally everything else is more likely. Fuel pump dying is far more likely.

Yea thats on my list of concerns also.. I gotta look at aftermarket pumps

[GTSBoy]

On 12/19/2021 at 1:14 PM, USA_DD_S2 said:

I gotta look at aftermarket pumps

Nope, you gotta measure the fuel pressure. Diagnosis before buyagnosis.

[USA_DD_S2]

On 12/19/2021 at 4:05 AM, GTSBoy said:

Nope, you gotta measure the fuel pressure. Diagnosis before buyagnosis.

10/10. Gotta get better at that. Does give me a reason to finally go get some of these old parts out of the car, but Ive been chasing this issue for awhile now and I miss WOT. Let me get on it

[USA_DD_S2]

On 12/19/2021 at 4:05 AM, GTSBoy said:

Nope, you gotta measure the fuel pressure. Diagnosis before buyagnosis.

Just stalled out on me 3 times trying to get started after lunch. Banged the top of the fuel pump cover a few times and the idle smoothed out and didnt stall again lol Heading to the shop tomorrow. Theyll be able to confirm and they have a few pumps on the shelf.

[USA_DD_S2]

Just to circle back around. Line from the fuel pump to the cap plate burst. Internal fuel leak, loss of pressure. Got a pump while theyre in there. Just threw 220whp down. Not bad for 26 years old. Thanks guys 👌🏾

[GTSBoy]

Good stuff. Score one for me, one for you and one for the workshop.