Strange idle problem with GTM SC Stage 1

SAM@GTM · 12-01-2011, 04:29 PM

Quote:

Originally Posted by toner123

I dont think your understanding what I said earlier. Not trying to be a *** when I said that, just want you to have all the knowledge so please understand that. There is no one step colder plugs for our car. The stock plugs in your car are the same ones the GTR use. The heat range on the stock plugs is heat range 8. There is no colder plug then that on the market currently. Just don't want you to go buy heat range 8 plugs thinking your getting colder ones when in fact your putting the same ones in your car that you have currently and end up wasting money. Like I said earlier your spark plugs are not the problem. Like Jordo said you would have a CEL if it was.

Frank just to clarify couple things Here

The GTR spark plugs are not the same as the 370Z plugs, also HkS does offer one step or two step colder spark plugs.

Sam

modme · 12-01-2011, 04:50 PM

While on the topic of HKS spark plugs, what's the recommended replacement interval? Every 20k miles? 30k miles? 50k miles?

SAM@GTM · 12-01-2011, 05:05 PM

Quote:

Originally Posted by modme

While on the topic of HKS spark plugs, what's the recommended replacement interval? Every 20k miles? 30k miles? 50k miles?

With a good running car( Good Tune ) 60 to 100 k

Sam

toner123 · 12-01-2011, 06:08 PM

Quote:

Originally Posted by SAM@GTM

Frank just to clarify couple things Here

The GTR spark plugs are not the same as the 370Z plugs, also HkS does offer one step or two step colder spark plugs.

Sam

Hmm weird. considering the fact on HKS website they show the heat range 8 plugs having the same exact part number as the one for the GTR. Also when I went to the dealership I was thinking of getting the GTR plugs, thinking they would be a little cooler and after pulling up the info he said they were already the same exact heat range already the two plugs and using the referance chart it would be equal to a heat range of 8. I just checked NGK website and they are also showing the same part number on the application chart with the OE sign.
Hmm guess I am wrong, just weird there is someone else on here who said he got the same exact information.

modme · 12-01-2011, 06:13 PM

I spoke to HKS a while back. They told me that their spark plugs are 1 degree colder than listed.

VQStryker · 12-01-2011, 06:28 PM

Quote:

Originally Posted by modme

I spoke to HKS a while back. They told me that their spark plugs are 1 degree colder than listed.

interesting

Fezzik · 12-01-2011, 10:02 PM

Mine does this as well everyone once inawhile. I never paid any heed to it. It only did this at idle and after a good run. My kit is running great. Best purchase I ever made

juld0zer · 03-10-2014, 10:14 PM

bit of a thread revival - could someone post up pics or a description of where the pcv vent FRESH air hoses have been routed?
ie. NOT the two hoses which go into the front of the intake manifold.
or a link to the install instructions?

theDreamer · 03-11-2014, 01:52 PM

http://www.gtmotorsports.com/Manuals...structions.pdf

juld0zer · 03-12-2014, 03:49 PM

cheers mate, i've just had a look at it.
i'm not a professional mechanic but i can share what i did to my Stillen G3 intake to resolve the same problem you're experiencing.

Page references are based on the labels at the bottom of each page.

Apologies for the use of two units of measurements - i'm from Australia where using both is acceptable depending on the context.

The stock breather system has these features:
RHS - 13mm restrictor orifice is in the junction where the breather hose barb pokes into the accordion pipe.
LHS (USDM driver side) - no restrictor. It is 16mm throughout. 16mm is approximately 5/8".

Page 61: The breather hose has a 5/8" inner diameter. Therefore the outer diameter of the barb it connects to on the supercharger intake is approximately 5/8". The barb's ID would have to be smaller (by quite a bit in this case, as it appears to have quite thick walls).

No issue quite at this point, as it seems to match the OEM setup in terms of hose inner diameter and the inner diameter of the barb fittings.

Page 70: Describes how a tee is used to join both cylinder banks' breathers together, drawing fresh air from the single 5/8" ID hose.

Because of this, the intake of fresh air is restricted by half at this point, and i reckon this is the cause of the sagging idle/stuttering issues you guys have experienced.

On my Stillen CAI, i cut off the LHS breather barb which has an ID of 12.5mm. Welded on a barb with ID of 15.5mm and my idle is about as good as it was with the stock intake now. RHS is left as Stillen made it.

As a simple test, i'd suggest disconnecting the tee and using a straight joiner for the RHS bank. ie. isolate the LHS breather.
For the LHS breather, clamp on a suitable small pod filter. Go for a drive and see what happens. Then try the idle relearn procedure if theres no difference (can be done without scan tools).

Ideally the breathers should draw from after the MAF sensors as the ccv system does recycle the crankcase fumes and burns it up. The fresh air drawn in to replace the fumes should be metered to ensure correct AFRs. But for a quick test it shouldnt hurt. The GTM setup draws from a suitable location but i reckon if you run another 5/8" hose to a new extra barb, it should unchoke it

12-01-2011, 04:50 PM	#32 (permalink)
modme Enthusiast Member Join Date: Mar 2009 Location: NY Posts: 345 Drives: G37 Rep Power: 16	While on the topic of HKS spark plugs, what's the recommended replacement interval? Every 20k miles? 30k miles? 50k miles? __________________ GTM Twin Turbo Stage 2\|GTR Turbo/Engine Gauges\|KW V3 Coilovers\|HKS Exhaust\|Oil Cooler\| Vossen CV1

12-01-2011, 06:13 PM	#35 (permalink)
modme Enthusiast Member Join Date: Mar 2009 Location: NY Posts: 345 Drives: G37 Rep Power: 16	I spoke to HKS a while back. They told me that their spark plugs are 1 degree colder than listed. __________________ GTM Twin Turbo Stage 2\|GTR Turbo/Engine Gauges\|KW V3 Coilovers\|HKS Exhaust\|Oil Cooler\| Vossen CV1

12-01-2011, 10:02 PM	#37 (permalink)
Fezzik Base Member Join Date: Jun 2010 Location: Chicago Posts: 182 Drives: G37 Vert 6mt White Rep Power: 14	Mine does this as well everyone once inawhile. I never paid any heed to it. It only did this at idle and after a good run. My kit is running great. Best purchase I ever made __________________ 2010 MW G37 Convertible 6MT Stage I GTM supercharger GTM oil cooler with thermastat 430whp / 340tq

03-11-2014, 01:52 PM	#39 (permalink)
theDreamer A True Z Fanatic Join Date: Feb 2009 Location: Texas Posts: 30,879 Drives: 370z Rep Power: 4210	http://www.gtmotorsports.com/Manuals...structions.pdf __________________ theDreamer's Z // Fast Intentions // Uprev // GTM // HKS // TEIN theDreamer's Silvia // URAS // GREDDY Houston Zs // Facebook // Twitter // Instagram

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Little issue at idle..	pty370z	Engine & Drivetrain	43	08-31-2015 11:23 PM
Strange 7AT Problem this AM...	Fly1 Motorsports	Engine & Drivetrain	17	04-27-2014 06:00 PM
stage 2 twin turbo problem!!!	LafitteZ	Forced Induction	19	09-23-2011 03:40 PM
Clutch feels strange, is this common or a problem	laze1	Engine & Drivetrain	11	01-27-2010 07:02 AM
HELP PLEASE: Engine Idle Problem	myfirstz	Engine & Drivetrain	21	06-29-2009 05:40 PM

03-10-2014, 10:14 PM	#38 (permalink)
juld0zer Enthusiast Member Join Date: Nov 2012 Location: Sydney Posts: 428 Drives: 11 Nissan 370Z MB M6 Rep Power: 138	bit of a thread revival - could someone post up pics or a description of where the pcv vent FRESH air hoses have been routed? ie. NOT the two hoses which go into the front of the intake manifold. or a link to the install instructions?

03-12-2014, 03:49 PM	#40 (permalink)
juld0zer Enthusiast Member Join Date: Nov 2012 Location: Sydney Posts: 428 Drives: 11 Nissan 370Z MB M6 Rep Power: 138	cheers mate, i've just had a look at it. i'm not a professional mechanic but i can share what i did to my Stillen G3 intake to resolve the same problem you're experiencing. Page references are based on the labels at the bottom of each page. Apologies for the use of two units of measurements - i'm from Australia where using both is acceptable depending on the context. The stock breather system has these features: RHS - 13mm restrictor orifice is in the junction where the breather hose barb pokes into the accordion pipe. LHS (USDM driver side) - no restrictor. It is 16mm throughout. 16mm is approximately 5/8". Page 61: The breather hose has a 5/8" inner diameter. Therefore the outer diameter of the barb it connects to on the supercharger intake is approximately 5/8". The barb's ID would have to be smaller (by quite a bit in this case, as it appears to have quite thick walls). No issue quite at this point, as it seems to match the OEM setup in terms of hose inner diameter and the inner diameter of the barb fittings. Page 70: Describes how a tee is used to join both cylinder banks' breathers together, drawing fresh air from the single 5/8" ID hose. Because of this, the intake of fresh air is restricted by half at this point, and i reckon this is the cause of the sagging idle/stuttering issues you guys have experienced. On my Stillen CAI, i cut off the LHS breather barb which has an ID of 12.5mm. Welded on a barb with ID of 15.5mm and my idle is about as good as it was with the stock intake now. RHS is left as Stillen made it. As a simple test, i'd suggest disconnecting the tee and using a straight joiner for the RHS bank. ie. isolate the LHS breather. For the LHS breather, clamp on a suitable small pod filter. Go for a drive and see what happens. Then try the idle relearn procedure if theres no difference (can be done without scan tools). Ideally the breathers should draw from after the MAF sensors as the ccv system does recycle the crankcase fumes and burns it up. The fresh air drawn in to replace the fumes should be metered to ensure correct AFRs. But for a quick test it shouldnt hurt. The GTM setup draws from a suitable location but i reckon if you run another 5/8" hose to a new extra barb, it should unchoke it