SR overboosting but no power. HELP - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

overdueBlaSiaN · 12-15-2014, 10:32 AM

my boost continues to build as I go higher in RPMs
even with this overboosting issue the car still pulls sluggish
I've changed the wastegate actuator and didn't help much

any ideas what could be my problem?

bmxer882x · 12-15-2014, 10:51 AM

Got a wideband? U could be going super rich or lean. Either would cause a huge loss in power.

overdueBlaSiaN · 12-15-2014, 11:15 AM

Quote:

Originally Posted by bmxer882x

Got a wideband? U could be going super rich or lean. Either would cause a huge loss in power.

Thanks for the reply
No wideband

overdueBlaSiaN · 12-15-2014, 11:18 AM

My mods:
Walbro 255 fuel pump
HKS BOV
HKS wastegate actuator
Godspeed exhaust manifold
3inch circuit sports turbo elbow
Aluminum CX radiator

silverarrow27 · 12-15-2014, 05:46 PM

What is considered "overboosting" for you?

Kingtal0n · 12-15-2014, 06:41 PM

Clogged cat? restriction somewhere it sounds like.

We need numbers. how much boost.

My immediate instruction to you is, disconnect the actuator so the engine doesn't boost at all anymore. Drive it like that for a while, see how it feels. If it still feels sluggish and slower than it should be, you have narrowed down your problem some. Do a boost leak check is next on the list.

overdueBlaSiaN · 12-15-2014, 07:18 PM

Quote:

Originally Posted by Kingtal0n

Clogged cat? restriction somewhere it sounds like.

We need numbers. how much boost.

My immediate instruction to you is, disconnect the actuator so the engine doesn't boost at all anymore. Drive it like that for a while, see how it feels. If it still feels sluggish and slower than it should be, you have narrowed down your problem some. Do a boost leak check is next on the list.

Boost used to stop at 7psi but just continues to climb

Update:
I drove the car to work today
Car didn't feel sluggish. Problem went away
So now my only problem is the overboosting issue

When you say unplug disconnect the actuator, do you mean take it out ? Or just unplug the vacuum line?

Also I don't have a cat

bataangpinoy · 12-15-2014, 07:41 PM

did you inspect the source line for the wastegate?

frostie00 · 12-15-2014, 08:05 PM

Do you have a manual boost controller?

overdueBlaSiaN · 12-15-2014, 11:12 PM

Quote:

Originally Posted by bataangpinoy

did you inspect the source line for the wastegate?

No I haven't but I know my line has a slight bend due to my cold pipe and Hotpipe being a tight fit. I'll try to fix that right now

overdueBlaSiaN · 12-15-2014, 11:13 PM

Quote:

Originally Posted by frostie00

Do you have a manual boost controller?

Yes I do
It's tee'd off to cold pipe and wastegate

Dboyizmlg · 12-16-2014, 12:13 AM

Quote:

Originally Posted by overdueBlaSiaN

Yes I do
It's tee'd off to cold pipe and wastegate

Lol, well that could be your issue right there.

You mentioned the turbo has HKS adjustable "actuator" correct?
This is what you do!
-take manual boost controller off
-run your vaccum hose from the actuator to the hotpipe
- check boost after this!

-if still over boost to like 13psi or so, then adjust the rod on the actuator a couple turns at a time to lower boost.

BTW just a heads up, those manual boost controllers are garbage.

overdueBlaSiaN · 12-16-2014, 11:36 AM

Quote:

Originally Posted by Dboyizmlg

Lol, well that could be your issue right there.

You mentioned the turbo has HKS adjustable "actuator" correct?
This is what you do!
-take manual boost controller off
-run your vaccum hose from the actuator to the hotpipe
- check boost after this!

-if still over boost to like 13psi or so, then adjust the rod on the actuator a couple turns at a time to lower boost.

BTW just a heads up, those manual boost controllers are garbage.

My Hotpipe doesn't have a nipple to put a vacuum line on. Can I just use cold pipe?
I still have the stock SMIC but aftermarket cold pipe that has a nipple

Dboyizmlg · 12-16-2014, 12:08 PM

^ yes you can still use cold pipe.
But.... It's recommended that the shorter the distance the better.
Either hotpipe, or compressor housing.

You should be ok with cold pipe for now though, later in the future you should get a quick tap fitting and drill it in the coupler, or nipple fitting on the hotpipe.

Dboyizmlg · 12-16-2014, 12:11 PM

I have my quick tap fitting on the turbo outlet coupler.
Bought it for about $10.00 from FRSPORT.com

overdueBlaSiaN · 12-16-2014, 03:28 PM

Quote:

Originally Posted by Dboyizmlg

^ yes you can still use cold pipe.
But.... It's recommended that the shorter the distance the better.
Either hotpipe, or compressor housing.

You should be ok with cold pipe for now though, later in the future you should get a quick tap fitting and drill it in the coupler, or nipple fitting on the hotpipe.

Ok so I did what you said and now my boost is back to 7psi
Thanks you so much !!

Dboyizmlg · 12-17-2014, 07:52 PM

Glad it worked out.

Fuego · 12-17-2014, 09:23 PM

Quote:

Originally Posted by overdueBlaSiaN

Ok so I did what you said and now my boost is back to 7psi
Thanks you so much !!

Set it to 11 and let it breathe like Nissan wanted it to.

12-15-2014, 10:32 AM	#1
overdueBlaSiaN Join Date: Jul 2014 Location: Oceanside Age: 27 Posts: 40 Trader Rating: (0) Feedback Score: 0 reviews	SR overboosting but no power. HELP my boost continues to build as I go higher in RPMs even with this overboosting issue the car still pulls sluggish I've changed the wastegate actuator and didn't help much any ideas what could be my problem?

12-15-2014, 05:46 PM	#5
silverarrow27 Zilvia FREAK! Join Date: Oct 2005 Location: Banning, CA Posts: 1,428 Trader Rating: (11) Feedback Score: 11 reviews	What is considered "overboosting" for you? __________________ 1989 240sx XE\|2002 Frontier SC CC LB 4wd\|2011 Pathfinder LE V8 4wd

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12-15-2014, 10:51 AM	#2
bmxer882x Zilvia Junkie Join Date: Apr 2013 Location: chandler Age: 28 Posts: 370 Trader Rating: (3) Feedback Score: 3 reviews	Got a wideband? U could be going super rich or lean. Either would cause a huge loss in power.

12-15-2014, 11:18 AM	#4
overdueBlaSiaN Join Date: Jul 2014 Location: Oceanside Age: 27 Posts: 40 Trader Rating: (0) Feedback Score: 0 reviews	My mods: Walbro 255 fuel pump HKS BOV HKS wastegate actuator Godspeed exhaust manifold 3inch circuit sports turbo elbow Aluminum CX radiator

12-15-2014, 06:41 PM	#6
Kingtal0n Post Whore! Join Date: Jul 2005 Location: South Florida Age: 38 Posts: 4,649 Trader Rating: (17) Feedback Score: 17 reviews	Clogged cat? restriction somewhere it sounds like. We need numbers. how much boost. My immediate instruction to you is, disconnect the actuator so the engine doesn't boost at all anymore. Drive it like that for a while, see how it feels. If it still feels sluggish and slower than it should be, you have narrowed down your problem some. Do a boost leak check is next on the list.

12-15-2014, 08:05 PM	#9
frostie00 Join Date: Aug 2007 Location: Washington Age: 37 Posts: 29 Trader Rating: (0) Feedback Score: 0 reviews	Do you have a manual boost controller?

12-16-2014, 12:08 PM	#14
Dboyizmlg Nissanaholic! Join Date: Aug 2011 Location: SoCal (I.E.), San Berdino, Colton, Redlands Posts: 1,665 Trader Rating: (17) Feedback Score: 17 reviews	^ yes you can still use cold pipe. But.... It's recommended that the shorter the distance the better. Either hotpipe, or compressor housing. You should be ok with cold pipe for now though, later in the future you should get a quick tap fitting and drill it in the coupler, or nipple fitting on the hotpipe.

12-16-2014, 12:11 PM	#15
Dboyizmlg Nissanaholic! Join Date: Aug 2011 Location: SoCal (I.E.), San Berdino, Colton, Redlands Posts: 1,665 Trader Rating: (17) Feedback Score: 17 reviews	I have my quick tap fitting on the turbo outlet coupler. Bought it for about $10.00 from FRSPORT.com

12-17-2014, 07:52 PM	#17
Dboyizmlg Nissanaholic! Join Date: Aug 2011 Location: SoCal (I.E.), San Berdino, Colton, Redlands Posts: 1,665 Trader Rating: (17) Feedback Score: 17 reviews	Glad it worked out.