Ok i put a thread on here a couple weeks ago about a boost leak. I got new intercooler boots, the one had a little hole in it i thought it was that. So i put them on and still doing it. I didnt pressurize the systems, but i took off my boost line to the block put air to it got up to 50 psi on the guage no leak there, the manifold bolts were loose tighen them up, Now here is the next part my turbo last night wouldnt spin freely i had to spin it by hand, now tonight it will spin freely spin with my hand and let go it will keep on. I thought the sound was my turbo bearings that were making the noise now im having second thoughts. Since one time it was now able to turn but now is. Can anyone tell me another place to check? I'm Sooooo lost right now. O yea it starts to make the noise at 5 spi and will stop as soon as i let off the fuel. I have mach 4's fass and a comp. It still does it with the comp on and off, I do have a P0236 code boost code but i think thats from, when i had my map sensor unplugged( i plugged it back in) seems to run fine but the noise is annyoing. Any ideas




Sorrys it's so dang long trying to explain the best i can!

 

wastgate maybe? could it be stuck open? what about the line coming off the boost elbow?

 

Whats the best way to see if its stuck open? i doubt it but it something to check..... I still hear like the phhhhsssss when i shift but it could be. I Checked the boost elbow line today, took it back off cut it to fit better ( the new boost elbow was a little longer) and tighend it back up. Still doing it. As i said my turbo didnt spin freely last night but did today and i just got in from workin on it and it doesn spin freely anymore????? Does this sound like the bearings? I dont hear my turbo whistle anymore if that help anyone in the determination. I hear it up un till 5 psi when the noise starts.

 

sure does, have you checked the play in the shaft?

 

oh yeah to check to see if the wastgate is working use compressed air, blow it in to the line going to the wg and you should be able to hear it working. You should be able to hear it open and shut.

 

Good idea, but careful with the air pressure or you WILL have a leaky actuator. 30 psi. max. Wouldn't hurt to retorque all the bolts on the intake manifold/preheater. (18 ft/lbs.) There's a picture of the intercooler pressure tester I built in my gallery, if you want to make one. Handiest tool I've ever built. Fits right on the turbo inlet.

 

Will that tester tell if the turbo is bad also?

 

No, not unless there is an external air leak. You can usually tell by the feel of the shaft if the turbo's bad. (any end play, or lots of radial play) I've seen a few where the shaft is stiff to turn. I usually attribute that to oil that got too hot in there after shutdown, and got sticky. It seems to be a temporary thing. I would hope some fresh engine oil and some gentle driving would clean it up. Spraying a SMALL amount of carb cleaner into the air inlet and then working the shaft back and forth might help, in case it's a buildup around the compressor wheel causing the resistance. Beware of runaway- the engine will run on cleaner that gets in there- use it sparingly.

 

I really have no clue now. The turbo was stiff then wasnt it was easy to turn but still made the noise and is now stiff again.... Im lost maybe i can get a sound clip of the noise with my phone and load it. Becasue i dont hear my turbo whistle anymore, just the whine as i call it but i think it could be classified as a Screeeeeeeeam. It is only at 5 psi and up and gets louder as Pressure builds. It does kinda feels sluggish too i dunno i just thought it wouldnt feel as sluggish with the comp and mach4's but i guess not, I just dont want to put all this money into a turbo and it not be it.... I want to identify the problem first, not guess like i have been doing already cost me $200 for intercooler boots that wasnt the problem

 

i forgot i dont have play in and out but i do side to side, up and down to me a pretty good bit but i dunno if thats just me being ****.