View Full Version : Power Mods help!car won't boost past 7psi
hbstock90
07-06-2009, 03:13 PM
like the title says. i tried to turn up the boost from 4lbs. to 8 and as soon as it hits 7lbs. its like some safety feature kicks in and the whole car starts jerking like i'm hitting a speed limiter, if any of you have ever done that then you know what i'm talking about. but i turned it down to 6.5psi and it runs great. i'm running an apexi vafc2, hks turbo timer, turboxs manual boost controller, xspower external wastegate,and ebay tial knockoff bov. is this a function of one of these items as a safety measure? if so how can i fix this? sorry if this is a noob question, but as you can quess its my first turbo car.thanks:D
hondalover00
07-06-2009, 05:25 PM
any cel lights coming on?...check vacuum lines for pinches....and what spring do you have in your wastegate?
TSiFTW
07-06-2009, 05:30 PM
Sorry but what kind of car?
SpooL'DGsR
07-06-2009, 07:01 PM
had same problem and it was vac lines.. g/l
Z0_o6
07-07-2009, 05:13 AM
It sounds like a Boost cut to me, it is a safety measure to keep your car from overboosting. is your car tuned or are you just running the VAFC?
scttydb411
07-07-2009, 06:46 PM
what motor, car, and has it been tuned?
SPOOLIN
07-08-2009, 08:49 AM
what motor, car, and has it been tuned?
yeah really, sounds like you are hitting a boost cut or its not tuned for that much psi and its either leaning out or pigging rich.
hbstock90
07-08-2009, 09:03 AM
thanks for all of the responses guys. no there aren't any cel's and the a/f ratios are right at 12 all the way till i hit 7lbs. so now i really do think it is a boost cut, and i looked online and the manual boost controller or vafc don't have a boost cut feature so now i'm wondering if its chipped. i pulled up the carpet and on the ecu is a phearable.net sticker, which really makes me think the guy before me maybe bought a chip from them and its on a basemap tune w/ a 7psi boost cut. the guy before me didn't really know alot about the car, because you would drive it maybe ten minutes and it would start sputtering and die, but all it was is that the tps was going bad. i replaced that and it runs great now.i guess this weekend i'll be cracking open the ecu to see if there is a chip in there. sorry about all of the confusion with this but i've only had the car for about a month and a half and i'm having to fix all of the previous owners mistakes. does anyone have a pic of a chipped ecu for reference, because i've never opened up an ecu before.thanks guys
edit**sorry its a 95 civic coupe, b16 swap,t3 and unsure of it being tuned or not, but the more i learn about the car the more i think not. have to wait till i get some money saved up for that because i'd rather have hondata installed and then tuned on that.
scttydb411
07-09-2009, 12:12 AM
the stock ecu can be tuned and since it's a pherable ecu it's been chipped. ditch the afc and get the thing tuned asap.
feel free to give me a call to discuss. 678-614-3596.
Batlground
07-10-2009, 01:21 PM
thanks for all of the responses guys. no there aren't any cel's and the a/f ratios are right at 12 all the way till i hit 7lbs. so now i really do think it is a boost cut, and i looked online and the manual boost controller or vafc don't have a boost cut feature so now i'm wondering if its chipped. i pulled up the carpet and on the ecu is a phearable.net sticker, which really makes me think the guy before me maybe bought a chip from them and its on a basemap tune w/ a 7psi boost cut. the guy before me didn't really know alot about the car, because you would drive it maybe ten minutes and it would start sputtering and die, but all it was is that the tps was going bad. i replaced that and it runs great now.i guess this weekend i'll be cracking open the ecu to see if there is a chip in there. sorry about all of the confusion with this but i've only had the car for about a month and a half and i'm having to fix all of the previous owners mistakes. does anyone have a pic of a chipped ecu for reference, because i've never opened up an ecu before.thanks guys
edit**sorry its a 95 civic coupe, b16 swap,t3 and unsure of it being tuned or not, but the more i learn about the car the more i think not. have to wait till i get some money saved up for that because i'd rather have hondata installed and then tuned on that.
It sounds like boost cut. Just have the boost cut moved up and you should be fine.
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