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hey guys first post in this section, mainly cos i just traded the ol' silver bullet for a red streak 2004 SRT-4. the only mod that i know of is supposedly the first owner installed a larger waste gate. i think its true because the check-engine light came on when i got it home friday and i checked for a cel and got # P0234 which is "engine overboost condition" plus i can hear a "fluttering" sound coming from the turbo (or that general area) when it spools up and also the boost gauge flies past 20 p.s.i. i'm pretty sure i'm not supposed to have that much boost from the stock engine. plus it feels like its not pulling hard, at least not for the 230HP i'm supposed to have. its also dumped the boost a few times (i guess thats what it is, i dont know much about turbo engines). i'm just driving along, accelerating normal and around 3k to 4k RPMs in third or fourth gear when all of a sudden, its got nothing; liked it dumped the boost and it feels like i just drove thru a deep puddle. i let off the gas, upshift, and go about my business. i know that cant be good for the engine so i've been driving easy for a couple days. i unplugged the neg. battery cable to reset the PCM and that took care of the check-engine light but the boost stills builds more than 20 p.s.i. do any of ya'll know what could be going on and how to fix it? i tried to add more preload to the WGA but it didnt seem to help. plus i couldnt figure out how many times to turn the little rod. thanks peeps.

If the wastegate was changed then the spring inside of it is probably set for a much higher boost level. I would go back to a stock wastegate. Also check the wastegate signal line, make sure theres no kind of boost controller installed (i'm assuming you'd know if there was though) and that there are no holes, tears, or anything like that in the line.

Is the boost consistently over 20 or just sporadically? Sounds like you might have some nasty boost spike going on there.

As far as the drops in boost, you should check the vacuum lines running to the WGA and make sure they are all in good shape and there are no leaks. As Ryan said, throw that stock WGA back on there (if you have it still). What brand is the current WGA?


.Chris

bombtrack07 wrote:hey guys first post in this section, mainly cos i just traded the ol' silver bullet for a red streak 2004 SRT-4. the only mod that i know of is supposedly the first owner installed a larger waste gate. i think its true because the check-engine light came on when i got it home friday and i checked for a cel and got # P0234 which is "engine overboost condition" plus i can hear a "fluttering" sound coming from the turbo (or that general area) when it spools up and also the boost gauge flies past 20 p.s.i. i'm pretty sure i'm not supposed to have that much boost from the stock engine. plus it feels like its not pulling hard, at least not for the 230HP i'm supposed to have. its also dumped the boost a few times (i guess thats what it is, i dont know much about turbo engines). i'm just driving along, accelerating normal and around 3k to 4k RPMs in third or fourth gear when all of a sudden, its got nothing; liked it dumped the boost and it feels like i just drove thru a deep puddle. i let off the gas, upshift, and go about my business. i know that cant be good for the engine so i've been driving easy for a couple days. i unplugged the neg. battery cable to reset the PCM and that took care of the check-engine light but the boost stills builds more than 20 p.s.i. do any of ya'll know what could be going on and how to fix it? i tried to add more preload to the WGA but it didnt seem to help. plus i couldnt figure out how many times to turn the little rod. thanks peeps.

less preload! less preload! loosen the wg arm 10-15 threads then drive and tighten till you reach 17lbs

it spikes to 20+ p.s.i. if i accelerate too fast so i have to do it slowly which sucks cos i wanna go fast lol. i keep getting different answers; some say more preload, others say less preload. i would figure more preload so the wastegate would open sooner to bleed off boost. another thing that sucks is i dont have the stock wastegate. i have no clue what brand the current one is. i'm taking this bi0tch to the dealership after work to have them work at it (still have a warranty).

I would put a stock wastegate back on before going back. They can void your warranty if your overboosting it. Which they're going to know your doing because of the code and aftermarket wastegate.

i need a stock wastegate. how much do those generally cost? i need to find a junkyard... how hard is it to install a wastegate?

It isn't hard at all to install. Should take about 5-10 mins, if you include pulling the aftermarket one off first. Good luck finding an SRT in a yard...you are better off looking for a used one on here or SRTforums.


.Chris

wait wait wait... are we talking about the actual WASTEGATE (the part in the manifold) or the wastegate ACTUATOR (the part bolted to the side of the turbo)?

The wastegate itself is just a flap of metal, not much to go wrong there. The wastegate actuator (WGA) is attached to the wastegate and moves it based on boost pressure. So, we are talking about the actuator.


.Chris

okay good, i'm on the same page then. yeh the WGA is easy as balls to take off. i did it last night and i'm about to do it again. how can i tell if it's aftermarket? there's no name on it but there is a couple of part numbers.

I would have to see the actual wastegate to tell you for sure but any aftermarket unit I have ever seen has the manufacturer logo on it somewhere and usually it is plainly visible when installed on the car. I'm wondering if maybe you have a Stage 2 WGA because I don't think that has a logo or name on it. You can search those part numbers on Google and see what you come up with.


.Chris

i'll post a pic later tonight when i get the camera. also, i dont know if this one is adjustable. i keep turning the arm but it doesnt seem like it makes a difference. still spikes way past 20 p.s.i.

First off, I just want to clarify: Less preload on the WGA = less boost

As you compress a spring the force required to keep compressing it increases. So the more you preload the WGA the more force it takes to open the wastegate, which means you build more boost before the wastegate opens.

You want less boost so you need less preload. If you wga is adjustable, you should screw the arm out (making it longer) to lower your preload.

If you can't get your current wga to work right, I have a stock wga that I have no use for. Just let me know if you want it.

okay everybody, i have new news. its NOT the WGA. i took it to the performance shop in town and he looked at it for 5 minutes and it turns out half of the vacuum hoses are hooked up wrong (he's worked on many SRT-4s at his shop). the previous owner took off the goodies before he traded it in and he did a half-ass job of hooking the hoses back up. the hose running to the WGA wasnt even the right one so thats why its boosting beyond belief. gonna pick it up tomorrow after work and i'll post again.

woot! she's holding boost at 15 p.s.i. and doesnt drop at redline. the guy said it has a stage 1 ecm so woot again! the shop is called Maximum Velocity Motorsports and its located on Hwy 2A in Ringgold, for anyone who is down in my neck of the woods. the owner Jon (he fixed my car) is very knowledgeable and is super cool. plus the girl at the counter knows her stuff too so thats an extra bonus.