Help with fuel cut?

[chang0901]

Guys i need some help with my engine..I have a "ca18det"I'm not sure, but i think i have fuel cut..thats why im askingWell this is the problem,i changed my stock turbo..cause i ****ed it upso i have 10psi with new turbo, thats stock i never touched the wastegatemy car is stock, no fuel regulator, no FCD, no boost controllerso when im running and press the gas pedal at full boost (10psi)the rpm dont pass over 5000 and it makes some strange soundlike Brrrrrrrrrr , And i checked the spark plug and its blackin the rear bumper where the muffler is ,black tooand in the exhaust, black smoke comes out when bov dischargesthe important thing is when i press the gas pedal till the psi gaugemarks 5psi, i dont have like fuel cut and it runs nice..what is the problem..? some help guysi checked the fuel pump and its okand my fuel efficiency is too poor, it does 16.8 MPG


Modified by chang0901 at 12:55 AM 12/19/2008

[DALAZ_68]

my question is what turbo did u get...?

[Ca_Silvia]

What plugs do you have in there now and what are they gapped at?

I had a similar problem when i swapped on my SR turbo. Went to a colder range gapped to .08 and it was all good.

[chang0901]

the new turbo is t28

and the plug is NGK BCPR5 in the head..it looks like carbon

just like burned..i think its too rich

[Anu]

Doesnt sound like fuelcut to me?On Euro cars fuelcut only happens at about 0,9 Bar ( around 13 PSI if im correct) and its more like you find your teethmarks on the steeringwheel when it kicks in.

Sounds more like a timing of ignition issue. Are you running a stock ECU and a stock fuelpump with a T28?

[chang0901]

the only thing i changed is the t28 turbo thats allthe ECU is stock, fuel pump toobut when i haved the t25 it was nice..10 psi, samei dont have any idea why do that..

[float_6969]

Have you checked the codes on the ECU? Is this a motor swapped S13, or was the CA originally in there?

[chang0901]

code 55 from ECU .i thinkand i never swapped..its 200sx non jdm

[Anu]

200sx in America is not the same as the euro 200sx is it?I think the T28 on a stock ecu might be the problem, the t28 will deliver more oxygen to the engine at 10 PSI then the t25 will, causing your engine to run lean and perhaps even detonate ( might be the sound you describe?)

[rico05]

Sounds about right. T28 with that hot of a plug and you are hitting fuel cut. I run a T25G and BCPR6IEX-11 and I can run up to 15psi on a hot day and ~17psi on a cold day just fine. You need a bigger MAF, a chip and more injector my friend. Plus, running a 5 range plug is not necessary. Run a 6 or a 7 then see what happens.

But I do have a question: "Brrrr"? When I hit fuel cut it is like hitting a wall; the motor cuts out and backfires as the motor basically shuts off. Sounds like you may actually have detonation. With that turbo you DO NOT need to be running a 5 range plug.

[float_6969]

I think the Brrr sound he's talking about is the ignition cutting out, or spark knock (the hot plug is causing the mixture to pre-ignite or not spark properly.

[Anu]

For a T28 better injectors and MAF arent immediately nescessary (assuming the US version of the CA18DET is the same as the one we get in our S13's)Most here in Holland run a Horsham developments Stage 2 chip with the T28, with the following list of mods:

Free flow air filter Free flow exhaust Boost controller to achieve 15psi boost pressure Uprated intercooler T28 turbo from an S14 200SX Super unleaded fuel (>97 RON) Uprated fuel pump ( mostly a walbro, 255 liter / hour )This will produce around 270 bhp

See also:http://www.h-dev.co.uk/product...ec09c

I know of a french guy running a custom chip with the t28, wich in addition to the above list also has an S14 MAF and 555cc injectors, not sure how much HP he puts out though.The chip also removes the Fuelcut, though i really dont think thats the problem, as described above, fuelcut is like hitting a wall.

[chang0901]

first of all thanks to all person who replied in the posti really apreciate guys..and i think rico05 is right, its not fuel cut..my friend have a jdm subaru wrx '98 16 psiand he have fuel cut..and it feels like the engine stoped a very short timeor hitting a wall..my car have detonation not fuel cut..so Anu u saying that t28 delivers more oxygen than t25 at same psi ?and i also tested with plug grade 7 and it burned too ..lol ?so its ok if i use s14's MAF ? and 555cc injectors ?

[Anu]

A t28 is a bigger turbo, thus produces less heat, and less heat means more oxygen and more power, at least thats how i understand it. A T25 at 1 bar will produce around 220hp with the HD stage 1 chip, the T28, with the same mods ( so stock injectors, uprated fuelpump, intercooler and freeflow exhaust and intake ) with the stage 2 chip will produce around 270hp on 1 bar boost.

Just putting in 555cc injectors and an s14 maf wont solve the problem, that was just an example of what someone used in addition to the mods i mentioned above it with a custom chip.

I think you need a mapped ECU for this, but I'd put in some extra mods, else you'll pay money to map a chip for just the t28, wich seems kind of a waste if you plan on doing more to the car performance-wise.

[ca18detgabby]

first of all thanks to all person who replied in the posti really apreciate guys..and i think rico05 is right, its not fuel cut..my friend have a jdm subaru wrx '98 16 psiand he have fuel cut..and it feels like the engine stoped a very short timeor hitting a wall..my car have detonation not fuel cut..so Anu u saying that t28 delivers more oxygen than t25 at same psi ?and i also tested with plug grade 7 and it burned too ..lol ?so its ok if i use s14's MAF ? and 555cc injectors ?

You need to remember that the S14 in holland has a SR, not a KA like a US S14.

its ok to upgrade your maf and injectors, but you need to be tuned to do so......... or your engine will run real funny.

sounds like you need to read up on turbos and the science of how their work..... without understand the basics, solving more complex issues is very difficult.