cant build over 19 psi and my car is running much slower

[jonk00000]

i cant build over 19 psi and my car is running much slower then normal.

my boost controller ball froze so i spiked to 30 psi maybe a little over but im not sure that is what may of caused the problem.

my car sounds completly different when i get on it

I usually run 25 psi no problem w/ a gt3076r turbo 38mm external waste gate

since i spiked ive had this problem

ive fixed every boost leak, compression test 150 153 140 150, cylinder leak down test shows 11 to 14% leakdown on all cylinders, i sent my turbo out to PTE and they said it was fine just a little carbon build up, i took my wastegate apart it looked fine cleaned it, ive checked mechanical timing and re-done base timing, complete tune up, my air fuel is fine and drive timing is good.

any suggestions will be much appreciated

 

[turbotalawd]

Did you maybe hook up the boost controller backwards?

 

[jonk00000]

no, ive also tried pulling the line off the wastegate to where i should get max boost and still 19 and i noticed at around 5800 rpm it will drop to 15

 

[1badgstdude]

Manual Boost Controller? Or Electric?

 

[jonk00000]

manual

 

[bacalhau16]

What kind of cat do you have? Test pipe or other, could it be clogged?

 

[jonk00000]

rnr 3" turbo back w/ o2 eliminator

maybe ill try runnin only down pipe

 

[jonk00000]

is it possible that i lifted the head when i over boosted???

my coolants arent mixing .

does any one have any help full suggestions ????

 

[Noogabox]

is it possible that i lifted the head when i over boosted???

my coolants arent mixing .

does any one have any help full suggestions ????

It sounds like you are not getting fuel in the upper RPMs. I would try to lower boost back down to 15 and see how it reacts. What did the plugs look like when you removed them? If they were white on the ground prong and around the electrode you are not getting enough fuel to support the RPM/ Boost. If they are normal or still black. If you car reacts perfectly to keeping 15 pounds all I can say is you are loosing boost somwhere, a leak or bearing is shot. Most the time its exhaust clogged or too small that prevents boost at higher RPM but if you have no Cat and 3 inch exhuast that sure is not it. What sprink are you running in the wastegate? If you connected the Boost signal hose to the wastegate directly then you should get a little under the boost level the spring is rated for. If everything works without the boost controller but then doesnt with its of course the controller.

Take in mind a vaccum line may have split or the inside of the wasgate is leaking boost ALOT. You have a leake somwhere. Have somone smoke the system with pressure and you will find it.

 

[bacalhau16]

If you lifted the head, and your headgasket is now to blame, you would be overheating, or blowing smoke or you would have mixing fluids. Try a boost leak test then.

 

[jonk00000]

fluids arent mixing and im not overheating, is there any chance it could still be the head gasket ???

 

[Supa Dexta]

Could it be? yes, Are we gonna be able to tell you.. nope. Pressure testin' time.

 

[jonk00000]

ive fixed every boost leak, compression test 150 153 140 150, cylinder leak down test shows 11 to 14% leakdown on all cylinders

 

[Supa Dexta]

I wonder if your turbo isn't putting out what it should. If your saying everything else in in check it's possible, but harder to test.

 

[jonk00000]

yea i thought it might have been my turbo so i sent it out to pte for a rebuild and they said it was in good shape and didnt need one.

 

[Noogabox]

I wonder that too! If the turbo just isn't putting out what it is suppose to ( or if its being overboosted for the compressor wheel) then everything can be perfect and still wont flow air well at a high boost level.

Please Post the part number for your turbo. The exhuast and compressor trim and size. Note what housings you have in mm if you know. I seriously wonder if its just out of the turbos flow range. Is there any play in the shaft up and down or forward and backward!?- Somtimes Boost will leak from arount the housing edges too. You may need to use a thin layer of spray copper gasket just on the mating edges.

 

[knochgoon24]

^^ I don't think we need those numbers...

Being he ran 25psi before, the turbo should still be able to put out 25psi now. The turbo doens't suddenly become physically unable to produce boost, especially because he even said he sent it in to PTE and it checked out ok.

Look for cracked vacuum lines.

 

[jonk00000]

this might be part of the problem but i cant get my boost controller to work, its either 12 psi which is the stock spring in the waste gate or 18-19 psi and the car sounds wierd like the motor is being silenced

 

[jonk00000]

any ideas? anybody ?

 

[lazyazzdaddy]

I've heard of exhaust leaks causing problems like this...I cant say if thats your problem or not and considering you have remved the turbo and sent it in I would have to assume that you installed new gaskets when you put it back in... if you did'nt i would check the exhaust inlet sde of your turbo. if air is getting out there it is'nt going to spin the wheel with the force needed to reach 25 psi. I've had the same problem you are haveing and found my mbc was bad. also on your waist gate I was under the asumption the you need to match your spring rate to atleast half of your boost psi... 12X2=24 running 25 psi may have worked untill you over loaded it and possably lost some of your spring tension and thats why the problem is showing up now.