Boost and Wastegate Issue (t25)

[Spanky_DSM]

My car is running extremely rich with horrible gas mileage. T25 is in good condition.

I did a wot pull and it peaked to only 15psi with no boost source connected to the wastegate.

So i did a boost leak test up to 20psi with no leaks with the wastegate unhooked, then did a second test with the wastegate hooked up to a boost source and still held 20psi.

Shouldn't it have only boosted to wastegate pressure and not held 20psi?

My car feels powerless. Everything is stock besides exhaust, intake, and 1g bov.

What would be the cause for the car not building more than 15psi at wot with the wastegate unhooked to a boost source. I hear a loud wooshing noise, like a boost leak but doesnt have any. Im still running a Recirculated bov.

 

[handsome_black]

Mod list. Where are you getting your 15psi boost reading from?

 

[Spanky_DSM]

Manual boost gauge.

Mods are intake, full 3 inch exhaust, and 1g bov recirculated.

Car is powerless, and i just checked timing with everything checking out.

Here are some pics i just took now when checking for tdc, I know its a few off but it should effect it horribly, correct?

 

[handsome_black]

Is your boost gauge stock or aftermarket?

 

[Spanky_DSM]

Aftermarket,

 

[Insane20]

Check the hotside on that t25. It may be cracked or broken by the waste gate flapper or the flapper it self may be messed up causing exhaust to escape before it can spin the turbine

 

[Spanky_DSM]

Damn its a pain taking off the o2 housing with the turbo on, I wish i had done it while it was off, I will definitely look into that.

Thanks.

 

[Diamond Star Werks]

15 psi is, what its supposed to push. Thats normal. Boost 20 & it won't last long.

 

[Archer Fabrications]

^this

 

[Insane20]

No he is saying it only gos to 15 with the waste gate not hooked up as in it's clOsed

You would think with the gate closed the turbo would at least put out 18 psi

 

[Diamond Star Werks]

The spring may be weak and the brackets tend to bend out of place. Had this happen to my gf car. Couldn't get it to boost past 6-7, idk if I unhooked it though think I did, bent the bracket some and it did alil more.

 

[Spanky_DSM]

I already know the turbo wont handle high psi.. my whole point is that it wont build past 15psi with the wastegate unhooked to a boost source.

Im about finishing taking off the turbo.. ill let you guys know in a bit what i find.

Update..

I just got done putting everything back and this is the only crack i found. It doubt thats my issue so any other input would be great. Could it be spark? Wires? im running rich. Maybe im knocking and its not letting me build boost? I dont have a wideband on this car so that sucks.

Just to add i dont know if its normal but a friend of mine put his dsmchipped ecu in my car and it was reading 9 degrees of timing. Is that correct?

 

[Diamond Star Werks]

9 degrees when? Check your o2 sensor. Also factory wot afrs are 9.6-10 in high load range so it'll run rich wot no matter what without a tune. That crack is nothing. Turbo is indeed in good condition?

 

[Spanky_DSM]

9 degrees when? Check your o2 sensor. Also factory wot afrs are 9.6-10 in high load range so it'll run rich wot no matter what without a tune. That crack is nothing. Turbo is indeed in good condition?

9* at idle.. and he said all the sensors checked out good while he was logging on his ecu in my car. No shaft play, no smoke at all what so ever, Revs perfectly no weird noises except a loud wooshing noise coming from the passenger side..

When i had my 18g fmic my car would spool and thats all you would here.

with the t25 i can hear the air rush through the system.

EDIT: maybe my ecu is bad?

 

[Diamond Star Werks]

If your car has power issues and runs crappy thats probably contributing to your boost issue. Check your plugs to be sure they aren't worn out.

 

[Spanky_DSM]

Plugs are good, ngk r bpr6es gaped at .028.. I pulled them about a week ago to only find them black. no oil residue.. more like carbon build up. O2 sensor i had was from autozone, and replaced it with a oem one and same results.

Im completely lost here. Car holds 20psi and vents slowly down due to crank case pressure which is recirculated but thats about as far as leaks go.

 

[Mischif]

Does your boost gauge read vacuum as well? If it does what is your vacuum reading at idle?

 

[Spanky_DSM]

The after market gauge only reads boost

 

[arabeclipse]

9* at idle.. and he said all the sensors checked out good while he was logging on his ecu in my car. No shaft play, no smoke at all what so ever, Revs perfectly no weird noises except a loud wooshing noise coming from the passenger side..

When i had my 18g fmic my car would spool and thats all you would here.

with the t25 i can hear the air rush through the system.

EDIT: maybe my ecu is bad?

The loud whoosh is the BOV.. which should be recirculated otherwise you will run rich between shifts.

 

[Spanky_DSM]

The loud whoosh is the BOV.. which should be recirculated otherwise you will run rich between shifts.

it is recirculated and im running a auto.

Does anyone think it could be spark? obviously i have fuel since im running crazy rich.

 

[Mischif]

I would have to say your mechanical timing is off, judging by the way your car sound when you crank it over. Just because your crank pulley lines up doesn't mean the belt is lined up correctly. You either need to pull the timing covers to verify timing, or hook up a vacuum tester and see what your vacuum at idle looks like.

That silver gsx i had at my house for a while was horribly out of time, even tho the crank pulled lined up.

 

[Spanky_DSM]

I didnt just check the Crank marks. I put a long object in cylinder 1 to get it at TDC and those were the pictures i took. And i also made sure the when i set it to tdc it was under the compression stroke. Im sure timing is correct.

 

[TallestHERETIC]

Do you have any holes in your exhaust? Like in the downpipe, cat converter, or muffler? Look for cracks, too.

A whooshing/whistling-type sound is definitely an exhaust leak.

When you checked your turbo, does the turbine wheel catch or rub on the housing when you turn it?

 

[Spanky_DSM]

I would have to say your mechanical timing is off, judging by the way your car sound when you crank it over. Just because your crank pulley lines up doesn't mean the belt is lined up correctly. You either need to pull the timing covers to verify timing, or hook up a vacuum tester and see what your vacuum at idle looks like.

That silver gsx i had at my house for a while was horribly out of time, even tho the crank pulled lined up.

Maybe it is timing, Ill try and get ahold of one that reads vacuum and post up what its reading.

 

[Black-Out]

I didnt just check the Crank marks. I put a long object in cylinder 1 to get it at TDC and those were the pictures i took. And i also made sure the when i set it to tdc it was under the compression stroke. Im sure timing is correct.

???........we need to see the cam timing marks on the top end of the engine in relation to the crank pulley after you lined it up on TDC, the pic you posted is pretty much useless because it doesn't tell us anything about the cam timing in relation to the crank in the static TDC position- If one or both of the cams are off it could feasibly cause a limitation in boost pressure regardless of the wastegate signal line being connected or off. It can also cause the car to be "powerless" as you put it...... Just installing a long object in the number one cylinder to locate the top of the stroke tells you (and us for that matter) nothing of camshaft alignment.

I guess what I'm saying is help us, help you- post up some pics of the both timing marks on the cams and the timing mark on the crank so we know beyond the shadow of a doubt that the timing isn't the issue otherwise we'll all be chasing our tails here........

Will-