I have a ls swapped crx si...... built for boost.... Recently while i was over at my tuners house we were trying to get the numbers right (Can't even get boost readings) as we drive and start to get into about 4lbs the car starts to shake and cut out..... we get some of the base map cleaned up and finally start to hit about 10-12lbs feeling pretty strong but still cutting out.... cant figure it out? We get back to the shop plug into the ecu and setting in N we begin to slowly rev the motor to see what's going on.... at about 1500-1700rpms the car starts surging? I got so pissed of messing with it i finally plug all my oil lines undid the intercooler and put my ls back stock until i could get some advice.... i've done some reading but cant find anyone that has had this type of problem? SOMEONE HELP ME OUT I WANT BOOST!!!! let me know if you need details about the motor intake setup anything..... not sure where else to go????

 

Well if you're having surging you should check your BOV, (But I guess that would be applicable if the surging happens when u let off the throttle)..

Uh, I think the other way it happens when the cold side is incapable of moving an excessive amount of air volume..I'm going off the top of the head with it so if anyone can chime in if I'm wrong it's welcomed..

Question, is this a kit tailored to your motor or did you just throw it together? What diameter charge piping, ect are u running..

 

everything has been tailored to this car..... the piping is 2.5 all the way around.... Skunk2 intake.....CP pistons golden eagle rods ac cam gears 3" downpipe t3t4 turbo....? anything else?

ALSO>>> Since the car has been back stock no surging occurs and she runs strong with no cuts.....?

 

Honestly I think 2.5" is to small, I honestly wouldn't run anything under 3". No way you could swap out for 3" piping real quick and see if that alleviates your issue?

 

what fuel pump are you running, and what is the injector duty cycle like when it cuts out?

 

walbro 255 with 440 injectors...... not sure what you mean by duty cycle?

 

if it matters they are RC 440's

 

i assume the turbo is a fairly small one then, like a 57trim t3/t4? if so 10-12lbs shouldn't be maxing out those injectors. duty cycle is how much of the injectors potential is in use. you don't want to run the injectors at more than 80-85% d/c. doing so can cause them to overheat and become less efficient.

basically i'm just trying to make sure you're not running out of fuel. what's the wideband show when it cuts? any cel being thrown, tried a different dizzy by chance?

 

yeah at first we had an obdo dizzy ended up switching it out for an obd1 got the jumper harness for that.... wideband stays steady at 13.xx.... and no lights are being thrown..... my buddy has a del with a b16.... he's thinking some dizzy issues also but the dizzy we replaced it with is brand new.... The problem doesnt just start with the 10-12lbs..... it used to be at 4lbs but after cleaning the base map we can get it up to 10-12 right now but the surge at 1500-1700 has us stumped? Also thought tpi sensor? any ideas help!

 

TPS* lol my bad

 

you're at that a/f when? WOT on a boosted car should be mid-high 11's. 13.*:1 is lean.

tps probably isn't the issue but wouldn't hurt to check it so you can rule it out. .5 to 4.5v is what you're looking for, and a smooth transition between the two points.

 

ill try tps along with 3" piping see if either of them help..... should know in a couple of days..... doin work son

 

and that 13.xx is gradually building up ..... not knowing what was really happening yet we didnt want to go WOT ***** to the wall to find out..... so at 13.xx going from about 40mph-60mph

 

ok cause partial throttle is one thing but WOT definitely should be lower/richer numbers. and i don't think the 2.5" piping size is your problem.

 

so any ideas on what the main problem could be?

 

other than what i've already said i'm not really sure. running colder plugs? it'd be easier if i had the numbers in front of me and i could see what the engine was doing. i dunno what you're having it tuned with but my buddy has an aem ems and it pretty much shows you everything you could possibly want to know or change lol

 

hondata s300 and laptop

 

MORNING BUMP!!!!!!!! talked to a couple other guys on different sites now and they are leaning towards either the tps, aicv, or the dizzy???? what are your takes on this?

 

Without being able to see what's happening on a screen as it happens..I'm sticking with the piping size being to small, if not the sole, partial, 2.5" is way to small imho.

 

threw on 3" charge piping.... same result..... come on people