Rebuilt S13 SR20DET Problems Please Help!

[nismodrifter661986]

OK, I just had my s13 sr20det black top rebuilt (stock t25 & E5 Ecu) Work Done: All new gaskets, rod and crank bearings, lightly ported head, Pre-Gapped Spark Plugs, Forged Pistons & a Valve job. Now the motor runs great at idle the problem I am having is the boost & IDK what to do the boost controller didn't fix the problem, Ok so when cold the boost is so jerky its almost undrivable but the turbo does sound healthy but also sounds like it operation improperly. And even after it warms up the problem does not completely go away, on vac the car slows down and the exhaust growls deeply and at boost it has a rough jerky powerband and just feels like im dragging an anchor behind me... If I let off the gas a bit its power on feels good like it should! This s*** aint right can anybody ease my suffering, the only thing I can think is (note: Im just at stock boost the controller is off cuz i wanna resolve this at a stock setting before I start messing with it!) Is that the adjustable waist gate might be set wrong or something IDK im at a loss!

Installed: Air Filter, 3" down pipe, 3" Cat-Back, Gutted Cat, HKS adjustable wastegate actuator, Fuel pump, Greddy Boost controller (Off) & Turbo Timer!

FYI all these add on's were already installed on the motor before it was rebuilt this problem stated after the motor was rebuilt... During the rebuild the turbo was not altered at all, just new inlet and outlet gaskets.

Modified by nismodrifter661986 at 4:23 PM 3/25/2009
Modified by nismodrifter661986 at 11:52 PM 3/25/2009

[dc1984]

since u say it is still stock t25, that means it is internally waistgated, so when u say, hks wastgate, im going to assume u r talking about the hks wastage actuator. never realy used one so not sure how the adjustments work on therewouldnt imagine it but i guess that might be a slight possibility.

do u have a boost gauge so u can moniter ur boost to see what its doing?

what do have the actuator hooked up to, what is ur boost source?it should be hooked up to just a boost source, no T's(unless boost controller) in the line and it shouldnt be hooked up to anything that has vacum. that means that if u have it hooked up to something off of the manifold, one of those three or four boost/vacum sources coming off of ther, then u r wrong. and from what i have heard, that can ruin ur wastegate actuator. which might possible cause a problem with it.but usually when an actuator is inop, ur problems would either be that u cant build up any boost, or that ur car just wont stop boosting.

maybe that is the problem, u hooked it up to vacum, ruined the actuator, now it wont open the wastegate and u are overboosting and u dont have a gauge to show it. just a thought. but, thats probly just some crazy theory i made up due to lack of info on ur particicular situation.

then again, maybe u just need a turbo rebuild. have u checked it for any shaft play? check for side to side, and in and out.

get back to us on this

good luck

[nismodrifter661986]

OK the vac line goes strait from the (Adjustable Actuator) t's at the boost controller unit and then hooks directly up to the Inter cooler pipe...

The car dose have a boost gauge and it spools and boosts but you cant feel the boost till 4k, & the turbo believe it or not has 0 play!
Modified by nismodrifter661986 at 4:14 PM 3/25/2009

[dc1984]

a boost source, boost is what pushes the actuator to open the wastegate, so a boost source is wherever ur getting that boost from. and u say u are getting it straight from the intercooler pipe which means u wont have no vacum. but u say it dont boost until well over 4k with a T25, that dont sound right. i have a stock t25 in my sr and i hit 10 psi at 3k in first gear.

what do u have ur boost gauge hooked up to?

u said ur boost controller is off but u mentioned that it is still T"d in between the actuator and its boost source(intercooler pipe) i would remove that so u have no possibilities of the T in the line messing with anything until u get this figured out. process of elimination.also, if ur still running a T25, with an adjustable hks actuator, i think u can have that set to somewhere around 12psi max, u dont need to be boosting any more than that on a T25 so i wouldnt even worry about trying to have that boost controller hooked up anyways. so again, just completly remove any T u have in that boost line.

as for the boost source, u mentioned it is coming directly from the intercooler pipe, what part of the pipe. where at? what i do with mine, is i put a nipple sticking out of the silicone hose coupler that connects my turbo to the intercooler pipe. then there should be a hose ran from that boost nipple to the wastegate actuator.

then again, if all this stuff was hooked up like this before the motor rebuild, then the rebuild could be the cause. or maybe the motor was just put back in wrong. u make sure and tightend town the motor and transmission mounts right? i sure hope so. to me, it kinda sounds like the car is shaking under load, probly not exactly a boost problem itself. but, it wont hurt by starting out making sure that u have ur actuator and boost gauge hooked up correctly.

get back to us on this

[nismodrifter661986]

Cool I will check that out thanks but I can assure you that the motor mounts are fine! I have to cruz this thing at no less then 35k or it just growls VERY LOUDLY and runs like total s***!

[nismodrifter661986]

Ok I bypassed the boost controller and it didnt make a difference so I hooked it back up (turned Off) ran it and yes no difference... I also checked my adjustable actuator and its set to the tightest setting the wastegate will allow, keeping the wastegate shut completely closed at the 7 O' clock position before boost; So I adjusted my actuator 4 turns counter clockwise putting the waist gate at the 6 O' clock position, this actually made the problem worse, I didnt put it back yet cuz cold down time is 3hours +... On my way out of work it was growling and back firing, short pops between 2k & 35k making the boost gauge flutter.... "I am aware that turbos operate better when hot, but this isnt normal" Anywho no change the turbo definitely operates better once ive ran it on the freeway and its piping hot! At that point it almost gives me no problem in first gear but once I shift up to second same thing just goes away faster. About an hour ago I capped off my the actuator line and drove down the street to fuel up, funny thing is the car ran beautifully perfect & it also was boosting consistently at 7psi (BOOSTS LATE BUT RUNS GREAT) "lol I made a funny" I was under the impression that capping your turbo line would keep the motor from boosting at all because that waist gate wont open??? WTF IS GOING ON??? HELP!

PROBLEMS RULED OUT: -Motor -Motor Mounts-Boost Controller-Fuel Pump

SUSPECTS: -Actuator?-Timing?
Modified by nismodrifter661986 at 6:31 AM 3/26/2009

[dc1984]

growling, sputtering, backfiring, not boosting till 4k. ill almost put money on the fact that u have an exhaust leak in between ur turbo and exhaust manifold, or somewhere in that area. more commonly, it will be that specific location though. their is a gasket that goes between their, could be worn and disintergrating, also check the bolts to make sure to turbo is tightend down to the exhaust manifold all the way. i can almost gaurentee that this is your problem.

if u do end up changing that gasket, might as well get the exhaust manifold gasket too while ur down there. check that out and get back to us