T25 on KA-T making noise and not reaching full boost! Help!

[ShimiBoi]

Hello all,

First off, thank you all for your help in advance. So I just turbo'd my KA with SR piping and a T25. I recently replaced the hose going to the wastegate from the intake piping (between the IC and TB) with a much longer hose that is about a foot longer to accommodate a MBC. However, I decided not to connect it but left the hose long. Now I have noticed that there is a weird noise coming from the turbo under boost and a whistle when slowing down in neutral, which never used to happen. Motor slightly bogs down then idles at 700rpm (normal was 900rpm). AFR is still mid 15s at idle. Boost gauge needle shakes between 6 - 7psi in 3rd gear at WOT. Turbo no good? Wastegate opening? Sorry for the long post. Please help.

[cotbu]

.................Lame

[ShimiBoi]

Anyone? Please help.

[ShimiBoi]

I meant I didn't use the MBC but the vacuum line is still connected to the WG. I'll check for oil in the pipes now.

[FaLKoN240]

Check for a boost leak?

[ShimiBoi]

Couldn't find any boost leaks. But I did notice that there is a loud rattling noise at 3000rpm in all gears. I'm fearing that the turbo is making the noise. But I'll look more into it tomorrow. Boosting seems to be fine. No metal know the intake piping before the IC. Not sure what is causing the rattle.

[Sileighty_85]

check for shaft play on the turbo.

[jr_ss]

7psi is max psi on just wastegate spring pressure. Post a video of the rattle.

[ShimiBoi]

I know there was some shaft play when I installed it a few weeks ago, but not that bad. I hope it is just something rubbing other than the compressor wheel.

[ShimiBoi]

So it turned out to be the downpipe bolts backing out. Thanks everyone for the help.
Anyone know what a good base timing is on a ka-t running an Enthalpy tune is?

[Duncan Steele]

Should have just gone SR...

[Duncan Steele]

Also did you upgrade the injectors? Adding boost is going to make the car run leaner, so your engine might blow cause it's running to lean.

[!Zar!]

Sounds like you have a boost leak between the maf and the turbo.

[motteramm]

So it turned out to be the downpipe bolts backing out. Thanks everyone for the help.
Anyone know what a good base timing is on a ka-t running an Enthalpy tune is?


Set your timing back to normal. The timing on any Rom tune (or any tuned ecu) is done in the ecu itself. You don't have to change timing at the distributor or anything.