no boost?

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RicKii``

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ok who knows much about turbos? problem...no boost is being made. yesterday was fine, today..will only hit 0 on the boost gauge and sometimes maybe to 0.02-0.04bar...makes a struggling noise when shes trying to make boost.. all pipes are fine as i can see.
ive got a feeling its the shaft? can someone with the knowledge let me know. cheers
 
check that your wastegate actuator arm hasn't come off the gate lever pin.

If it has .. it will make no boost because the wastegate will be open and exhaust gas will be vented into the exhaust dump pipe not the turbo housing (making the turbine spin) ie no boost!

or like you say the shaft may be broken, Take the front turbo intake pipe off stuff your fingers into the turbo intake, (motor off, of cause) and see if you can spin the compressor wheel freely it shouldn't have very much movement up and down or latterally just round and round, and definatly you shouldn't here any scraping noises.

this would be a bad thing!

I would put money on that the wastegate actuator arm has come off the pin.

hardest part there is (if it be the problem) is finding a small enf split pin. (or serclip depending what turbo you have) small paper clip will get you out of trouble.

JetGSR

or I could be wrong.
 
JETGSR said:
check that your wastegate actuator arm hasn't come off the gate lever pin.

If it has .. it will make no boost because the wastegate will be open and exhaust gas will be vented into the exhaust dump pipe not the turbo housing (making the turbine spin) ie no boost!

...

I would put money on that the wastegate actuator arm has come off the pin.

hardest part there is (if it be the problem) is finding a small enf split pin. (or serclip depending what turbo you have) small paper clip will get you out of trouble.

JetGSR

or I could be wrong.

+1 have come across this more than once
 
cheers for the quick replies, no shaftplay on the turbo at all :D, the wastegate pin is still intact, ive removed the bov and ran the stock one and it was still not making boost so the last thing to try now is the cat convertor. is it a common thing with the cat to do that? i mean it picks up well on no boost but once boost tries to come on, its just no fun.
 
wastegate not ceased??

basically preasur is drivernt he wastegate actuator open through your cooler piping, only thing i can think of is the actuator bein ceased
 
Check the cat next get under the car and give it a bang with your hand! If it rattles it's toast! (make sure the car is cool! the cats get extremely hot)

sounds obvious doesn't! not touching a hot cat, but you never know. ???

JetGSR
 
I used to hear my cat rattle when i turned the car off in the garage. Couldn't work out where the noise was coming from untill the day i lost boost. Pulled the cat out and the honeycomb was lodged hard into the rear end of the cat. I just opened up the casing, welded a 3" piece of stainless through and welded the casing back around. Looks like a stock cat, flows like no cat. Plus no more rattle and the turbo started spooling up quicker than ever. :D
 
just removed my cat today and what do you know..honeycomb is fully blocking the rear part of the cat. well had to gut it til i get the new one installed. thanks boys! was missing the feeling of boost..
 
Depending on how soon you are getting a new cat, i'd suggest getting some pipe welded through. My exhaust became really "droany" inside the car when i just had an empty cat. Also, my car didn't spool up aswell as once i put the pipe through. I remember reading a post (i think by clutz) explaining that the empty cat causes turbulance or somthing slowing down the passing exhaust. Made sense and worked for me.
 
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