[viper92086]

hey guys i've been posting boosting problem thread all over the place and i'm running out of ideas. Everytime i open a thread it seems to go dead... but basically what i have here is a na-t. everything is stock except the custom hard pipes. I already tested for leaks. THe car drives like a dream right after it is warmed up, but with continous driving it looses boost, car doesn't pull, feels like a NA. This is a constant problem. So far i checked timing, bought new plugs, replaced wires and tried multiple afms. I'm not lookin for any high horsepower in the future, i just want a stock na-t that runs like a dream any time of the day. I've had a few people suggest that my cps is going bad but that makes no sense since the cps is not temperature effected or so i've been told. Also btw this car has a 3" exhuast with 3" dp but stock elbow. Any one with an idea please let me know

 

[Jason T]

Do you get any codes ??

What timming are you running ??

Waste gate aucator is good ??

Are your knock sensors ok ??

Ecu temp sensors ??

Fuel supply good ??

Presure test your interooler pipes ??

 

[viper92086]

No codes at all

timing is at 8 degrees (i had it at 10 and was told to back it down a little)

wastgate is shimmed cause i thought the spring may be weak

knock sensors are fine since i'm not throwing codes

ecu temp sensor?? how do i check that

fuel is fine, car is actually running rich

intercoolerpipes checked out fine.


thanks jason, hopefully this helps you guys out

 

[Elusive_RR]

with no codes it sort of limits the things it can be.....my guess would be a wastegate problem.....is the vaccum line going to the wastegate in tact? also what made you think the wastegate spring might be weak?

 

[viper92086]

yup i just replaced that line going into the wastegate, someone else actualy thought it may be weak and told me to try shimming it, but i ended up with more boost at start and the same 5psi ending. i shimmed it with 3 washers btw. Is there any actual way of testing it?

 

[Elusive_RR]

what psi is it at when it runs good? and what psi does it end up at after it starts running poorly? does it start to miss at all? how long does it take b4 it starts to run bad?

 

[viper92086]

when it runs good 8-9 psi, about 5-6psi poorly. I don't notice any missing. It starts to run bad about 20 minutes into a drive. the car still idles and drives fine, it just boosts very poorly after this and it is something that happens all the time. thanks guys, hopefully this thread will be the last one i need to get this fixed

 

[viper92086]

update: well i found that my clutch fan was dead so i picked up a new one and installed FYI they are only 40 bux from autozone, toyota wants 170 for a new one. I will report back 2morrow after i drive to work

 

[Elusive_RR]

does the temp go up at all when it starts to run bad?

 

[Jason T]

yup i just replaced that line going into the wastegate, someone else actualy thought it may be weak and told me to try shimming it, but i ended up with more boost at start and the same 5psi ending. i shimmed it with 3 washers btw. Is there any actual way of testing it?

Try another acuator

ditch the shim idea stable boost first then modify

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=TC&Page=8

 

[viper92086]

no noticable temp difference when it starts to go bad, my theory is that the fan is spinning but not fast enough to cool the engine down, but not slow enough to oveheat. But here's the update, i drove to work this morning (1 hr drive) and i was able to boost the whole way without any problems. I can def hear the fan now, engine roars when i gun it... something i never heard b 4 i'll let you guys know if it happens again, thanks again.