i have a o5 mr ran it at the track over the weekend barely got 15.1 gets a nasty fell in 2nd like a fuel cut then bogs at 5,000 and up rpm but still boosting. then today i was beatin on it so see what the problem was and it got a real nasty fuel cut boost was off the guage and finally got a service engine light the code reads wastegate failure anyone ever have this problem and figure out what was wrong

 

chech the wastegate (boost) solenoid and if it is the wastegate actuator I have a adjustable forge one brand new for sale.

 

its weird though when its cold it runs awsome then once it warms up the thing becomes a dog

 

So, are you on the stock turbo, WGA, and factory boost control? Or, are you contolling boost via an EBC, or MBC? Is your car flashed? If so, for what boost level? What is the complete modlist?

 

the car is stock just a exhaust and upper i.c pipe no boost controoler it weird was just drivin it doesnt boost that hard at times it only goes just above one car then other times it goes to 1.5 and when it goes past 1.5 the check engine light comes on

 

i meant bar im goin by the stock evo mr guage

 

well when the car is cold the stock boost selenoid will control boost at a very low level untill the car comes up to temperature. I would check the vaccum lines that go to the boost control selenoid and wastegate to make sure they are ok and connected propperly the selenoid is located on the frame rail by the airbox. You may have a bad boost control selenoid.

 

idk when its cold it doesnt boost hard like it supposed to then when it warms up it still acts like its cold at times and other times it over boosts maybe the solenoid is getting stuck ?

 

Are you having a cold weather spell in your neck of the woods? Colder air temps can cause the car to act up. Maybe you should get a tune. Also, check that the inlet snorkel isnīt lifting due to faulty fasteners,

 

its either the solenoid or the line running to the solenoid, heres a test to see if its actually the wastegate actuator or the solenoid, take the boost line that connects to the wastegate n connect it directly to the turbo boost source line,now this parts important...roll into the throttle so u dont overboost, if your boost gauge goes over 10lbs of boost then your wastegate actuator is shot

 

yea we are startin cold nites here but the car has been gettin worse and worse over the past month and last friday went to the track car could barely do 15.1 lol thing is a dog

 

It couls also be a boost leak as well, check the aftermarket IC pipe couplers..

 

yea but would a boost leak make the car throw the check engine light for wastegate failure i could understand the low boost issue but its spiking high at times

 

You may want to crank in some additional wastegate preload. Try two complete turns of the turnbuckle located on the end of the actuator rod. Too little preload can cause peak boost to fluctuate up and down as well as limiting the peak that you can achieve.

 

I donīt think that wastegate failure per se is all that common of an occurence. There have been a few isolated cases reported on here of the flapper valve separating itself from the pivot arm. This can be traced to faulty spot welds during the manufacturing process.

As for the wastegate actuator itself: There really isnīt that much that can go wrong inside the canister, other than the diaphragm. You just donīt hear of diaphragms failing that often.