Q45 high idle

[boostfeddGSX]

Alright guys so I have a 2g with a 6 bolt swap as far as the throttle body and intake manifold I am running the q45 tb matched up to a jmf race smim. The throttle body does not have an idle speed control so when I start the car I have to let it warm up for a little manually by foot then I let the car idle it will idle dead at 1000rpm, but the thing is once the car is really warmed up it idles at 1500rpm I was wondering if the problem is because I am not running a idle speed control? Also my first guess would be to boost leak test the car and go from there what could it possibly be? I'm sure someone else is running a setup like this if you could point me in the right direction thanks.

 

[Purex2c]

Have you checked the BISS or any other air adjustment on it?

 

[boostfeddGSX]

Have you checked the BISS or any other air adjustment on it?

If I messed with the biss screw that would make my car idle worse at startup which then I would have to keep playing with the biss screw. Anyone else running this setup that would know what is going on?

 

[untouchablecc]

Hmm I don't know if those have a built in idle switch but on a 2g tps they do which tells the ecu to idle. Which tps are you using?

 

[Night devil]

Got this from a supra forum:

Q45 Throttlebody shaft leak fix
Those of you who run the Q45 TBs, I found a simple method of reducing and eliminating the shaft leak. At 2psi boost leak test, I would begin hearing a hiss from the shaft seal, primarily on the cable side. At 5psi, it would leak quite a bit more.

Granted this leak would probably not hurt spool or cause that much turbo inefficiency, I sought out to eliminate it.

I used two o-rings, 10mmx15mmx2.5mm. Remove the TPS and the entire cable assembly to access the OEM orings on each side of the shaft. Actually, the shaft rides on ball beaings which have rubber seals, not orings.

I simply greased up the two o-rings and placed them on each side of the shaft. Simply reassemble the TPS and cable assembly. This eliminated any hiss from the shaft at 15psi boost leak test pressure. I haven't tested higher at this point.

I eliminated all hissing at 15psi. Nice and tight. All this talk about shafts and rings and grease...

 

[4g63t]

You have to set up a fake idle switch when the tps is closed at 0% in link. But i assume you have done that or it would not idle hardly at all and your issue is a high idle.

http://www.dsmtuners.com/forums/newbie-forum/230365-infiniti-q45-throttle-body-merged-4-8-a.html
You need to read up on the tb there is a way to make the stock fast idle control valve work. but you have to run coolant to the tb.

Got this from a supra forum:

Q45 Throttlebody shaft leak fix
Those of you who run the Q45 TBs, I found a simple method of reducing and eliminating the shaft leak. At 2psi boost leak test, I would begin hearing a hiss from the shaft seal, primarily on the cable side. At 5psi, it would leak quite a bit more.

Granted this leak would probably not hurt spool or cause that much turbo inefficiency, I sought out to eliminate it.

I used two o-rings, 10mmx15mmx2.5mm. Remove the TPS and the entire cable assembly to access the OEM orings on each side of the shaft. Actually, the shaft rides on ball beaings which have rubber seals, not orings.

I simply greased up the two o-rings and placed them on each side of the shaft. Simply reassemble the TPS and cable assembly. This eliminated any hiss from the shaft at 15psi boost leak test pressure. I haven't tested higher at this point.

I eliminated all hissing at 15psi. Nice and tight. All this talk about shafts and rings and grease...

Why would you post somthing that clearly has nothing to do with the op's issue...

 

[Night devil]

Because had similar situation on my friends 1g build. Took us a week to find that leak. Tried another q45 samething. The rings were bad on both tbs. Then we followed the steps the guy wrote, ran better and held higher boost. Just incase if the problem was a throttle body leak, he is getting the heads up.

 

[boostfeddGSX]

Got this from a supra forum:

Q45 Throttlebody shaft leak fix
Those of you who run the Q45 TBs, I found a simple method of reducing and eliminating the shaft leak. At 2psi boost leak test, I would begin hearing a hiss from the shaft seal, primarily on the cable side. At 5psi, it would leak quite a bit more.

Granted this leak would probably not hurt spool or cause that much turbo inefficiency, I sought out to eliminate it.

I used two o-rings, 10mmx15mmx2.5mm. Remove the TPS and the entire cable assembly to access the OEM orings on each side of the shaft. Actually, the shaft rides on ball beaings which have rubber seals, not orings.

I simply greased up the two o-rings and placed them on each side of the shaft. Simply reassemble the TPS and cable assembly. This eliminated any hiss from the shaft at 15psi boost leak test pressure. I haven't tested higher at this point.

I eliminated all hissing at 15psi. Nice and tight. All this talk about shafts and rings and grease...

I will keep that in mind, but this is not pertaining to my question as of right now

You have to set up a fake idle switch when the tps is closed at 0% in link. But i assume you have done that or it would not idle hardly at all and your issue is a high idle.

http://www.dsmtuners.com/forums/newbie-forum/230365-infiniti-q45-throttle-body-merged-4-8-a.html
You need to read up on the tb there is a way to make the stock fast idle control valve work. but you have to run coolant to the tb.



Why would you post somthing that clearly has nothing to do with the op's issue...

Thanks man yeah the fake idle is already set in link. I will have to look into that thread you posted

 

[Burg2DaWorld]

Because had similar situation on my friends 1g build. Took us a week to find that leak. Tried another q45 samething. The rings were bad on both tbs. Then we followed the steps the guy wrote, ran better and held higher boost. Just
incase if the problem was a throttle body leak, he is getting the heads up.

Not to bring up such an old post but how did your friend check for the leak? What did he use on the manifold part of the throttle body to cover it?