Infiniti Q45 Throttle Body [Merged 4-8]

[SilverJester]

first off, I am posting in this forum because this is where I found part of my answer...but please move if it's in the wrong place.


I have a 2g which means I have 4 wires going to the TPS. the q45 tps has one pig tail w/ 3 wires and a short harnes w/ 3 wires. So far what I've been able to find is the the short harness is for the actual TPS and the pigtail is for the "idle validation circuit". I'm not sure what that means but I found it on some supra forums. I know that the difference between the 1g and 2g tps is that the the 4th wire (which ells the ecu if the throttle is closed) is seperate on a 1g. Could this be the same thing as "idle validation"?

So far this is the info I have come across as far as wired and what they are for:

q45 tps harness (not the pigtail):
-Red is the 5 volt input wire
-White is the TPS signal wire
-Black is the sensor return wire

2g tps harness:
1 - Green/Yellow (+5v Sensor Power)
2 - Brown/Red (TPS output voltage)
3 - Yellow/Red (IPS switch)
4 - Black (Ground)

Ok so I'm still a little confused on what wires to connect so if anyone has experience or more info t add I would appreciate it.

 

[Slow99x]

The DV/DT Fab kit is made for the Q45 throttle body if you get the race version. I have the street kit and I plan on upgrading when I have the money for his SMIM and Q45 tb. The difference is the upper piping.dvdtfab.com Sorry man I didn't look to see what year car you have. They only have "kits" for the 2g and Evo. He's played with doing a 1g but the core needs to be longer or shorter to clear the supports.

 

[nanokpsi]

Its very easy to adapt. I have the dejon race kit and just cut the upper ic pipe and ran a 3.5" gm maf. I connected the MAF to the TB with a 3.5" silicone elbow, and have a 3.5" to 2.5" reducer on the other end of the MAF connected to the rest of the ic pipe.

 

[spinz4]

That pipe is meant to be used with the Buschur Race FMIC and Buschur sheetmetal intake. It most likely will not fit with another fmic or sheetmetal.

Thats funny I have neither a buschur FMIC or intake manny and it fits just fine......Guess im luckt and dont know anything......Do yourself a favor and call Buschur....

 

[man_of_saturn]

Pigtail is it needed? Got a q45 and JMF manifold trying to get it hook up.
Thanks!

 

[nanokpsi]

Pigtail is it needed? Got a q45 and JMF manifold trying to get it hook up.
Thanks!

If you are looking at the tb as it is installed on the car, you will use the wires coming from the "top" of the q45 tps, not the plug that is in the traditional DSM TPS sensor position.

 

[Slippi84]

Ok I have a 2gnt and I'm gonna be throwing a q45 on my obx manifold and didn't see anyone come up with any solutions for people that don't have eprom ecu access. I'm trying to find out what will happen if I don't hook up the ips and hook up the res of the stuff per the wiring comparison the OP posted. By the way can I even use that as I'm 420a and not 4g63?

I'm going to be putting a q45 tb on my 2g(it's a 420a so keep that in mind) and know that you use the top wiring harness/pigtail/connector whatever you want to call it for the TPS but the main problem seems to be the idle switch. I don't want to get everything, weld the appropriate flange on my manifold and then be beat because I have a tb setup that makes the car run like crap. I don't have dsmlink as it's not avaible for 420a(crying shame) so I can't just compensate with a tuning device so I'm left to either a mechanical adjustment as in the screw or to figure out a wiring solution. So in a nut shell looking to see how you guys solved the idle problem??

 

[turbodsm18]

Is is a turbo 420a?

Cause isnt the q45 thottle body like 90mm. Thats a bit overkill for even a moderately sized turbo motor

 

[Slippi84]

Your right but I'm trying to do some diffrent with this setup. I might not even boost the car I might go high compression with spray. The stock tb on a 420a motor is like 50mm or something crazy small and from what I have read the only downside to large tb's is twitchy throttle which is ok with me cause I have a heay foot anyway

 

[black91awdturbo]

I have searched but only come up with people saying it will work but nothing saying who to make it work. I am putting together a new set up, and I want to use the Q45 Throttle Body with my new Jmf Manifold. My question is this does and one have a write up of how to wire it in correctly and what needs to be done with my throttle cable? And for the record yes my intake manifold is flanged for the throttle body already. Thanks and hope to get some help asap!

 

[spendone]

Its really easy to wire up. the only tps plug that you will be using is the gray one. There are 3 wires....power,ground,signal. Match the red with green/red, black with black,green, and white withe green, white. This is for a 1g of course. Aside from that, you will need to drill out the throttle cable hole on the throttle body. The nissan hole is smaller. Good luck with it.

 

[black91awdturbo]

great thanks for that info thats what I needed!!

 

[spendone]

No problem. Glad to help.

 

[Slippi84]

I am not 100% finished with this as the old manifold has proved to be a so much bigger pain in the ass to get off then I thought mixed with lack of light. Anyway before I get into uploading pictures and what not ..WHAT THE HELL IS THIS THING RIGHT UNDERNEATH THE STOCK MANIFOLD??? There is this huge heat shield or metal support box setup right underneath the stock manifold which is the sole reason for my troubles. You have to be mr fantastic to reach up and around to get past it and the bolts holding it up are like shielded and I didn't even waste my time trying to take it off. ANyway that's enough venting.

If anyone has been folowing this obx project of mine(obx manifold thread) you'll know everyone told me it wasn't worth doing this and it's overkill well hopefully very soon I'll know the answer to that. I had a flange and a spacer welded and bolted to the obx and a 80mm opening cut out for the q45 tb. I am cutting and rewiring the stock q45 tps right into the stock wiring per the write ups I have found about turbo 2g q45 insalls. I will get pics up tomorrow of manifold which has had all the mods talked about in the obx manifold thread. It looks very clean and with cams and a little head work should make for a mean intake setup. I'll get some pics and let them do the talking.

Just to give people a Idea of how much this cost so other people after me can choose to or not to take this kind of path the manifold was $150 on ebay which came setup for the map sensor and everything else underneath not along the back like the stock or normal obx manifold which makes installing and what not easier. The q45 tb I got for $150 of ebay as well with tps and aluminum flange that was used to weld up against the obx manifold. If you know how to weld and port yourself you could save yourself some money but it cost me about 200 bucs to have a spacer made so the linkage would clear as it hit the manifold with just the flange and to have the ports opend up and smoothed out to increase and promote flow. So it would take $300-$500 bucs for a setup similar to this. To me I think it's worth it and owuld do it again as smims a lone for 4g63's are about that much a lone.

 

[InfiniteGSX]

I've only seen that box once... it was on my black car's engine... but none of my other 420a cars. other then that, there's the two brackets...

 

[Slippi84]

I've only seen that box once... it was on my black car's engine... but none of my other 420a cars. other then that, there's the two brackets...

Consider yourself lucky that box is a pain in the ass like you would not believe. I knew I wasn't gonna reuse it so I was gonna use the hit now ask later tech but IT'S METAL!!! I don't know why or who decided this was a good idea but he should be taken out back and shot. ANyway I think I figured it out and i'm gonna take care of it tomorrow which will just in time cause my prothane mounts which shoudl have been in a week ago are coming in. I'm gonna take the old manifold off put the mounts on then put the new obx manifold with q45 on. I still haveto figure out what I want to do intake wise. I was thinking about having the local muffler shop I sell parts to weld me a 3"-4" AEM V2 style cold air intake but I"m afraid it will be too heavy using steel or w/e and need a bracket which seems overkill for a intake setup but to really utilize this mod you need atleast a 3" intake. Actualy a 3" coupler fits inside the q45 opening WTF.

 

[InfiniteGSX]

I think its only one or two bolts that hold it on... I really can't remember... I dont even remember wtf its for...

 

[Slippi84]

I think its only one or two bolts that hold it on... I really can't remember... I dont even remember wtf its for...

It looks like it's bolted to the block in two places I"m gonna try and get to em tomorrow def looks just like a heat shield for the harness or whatever else is under the manifold but idk just a pain in my ass I would have a lot more info if it wasn't for it cause I would be done. But I wont let this turn into a venting session about that dam box I'm bored and can't sleep so lets see if we can get these pics up tonight

 

[bullettdsm]

Good to see you're following through. Sometimes you just gotta do it

Are you sure it's not the cruise control box you are playing with? Couple of vac lines coming out of it. I've broken down my share of stockers and the cruise and two intake supports is all I remember taking off.

MB

 

[Slippi84]

Good to see you're following through. Sometimes you just gotta do it

Are you sure it's not the cruise control box you are playing with? Couple of vac lines coming out of it. I've broken down my share of stockers and the cruise and two intake supports is all I remember taking off.

MB

The cruise controll is a small box at the top left of the engine bay but the intake support sound more like what it is but it's not just two brackets its literally a box or metal plate that is long bolts up to the block in atleast two places I went and looked last night and then bolts to the lower intake manifold on the first and last runner. I will take good pictures tonight cause my phoen sucks and I couldn't take any good ones last night.

Yeah I'm glad I followed threw too it looks real good and should perform quite nicely as soon as I pick up a set of crower stage 2's and get this head cleaned up a little.

 

[Slo2gen]

I know what your talking about, all it is is a brace, you don't really need it. I didn't put it back on mine from when I changed the HG the first time. There is already those two supports \ / so I didnt reuse it.

 

[Slippi84]

I know what your talking about, all it is is a brace, you don't really need it. I didn't put it back on mine from when I changed the HG the first time. There is already those two supports \ / so I didnt reuse it.

I"m gonna make a video of me bashing it after I take it off and post it.

Maybe you can help me out though the reason i'm stuck is there are two bolts and by the way the supports are on the first and third not fourth runner that bolt to the outside of the bracket to the lower plenum. Those came off easy with like a 13mm socket problem is those outside brackets are connected to that dam box and behind that is another nut but I can't get to that other not because those outer most part of the bracket doesn't back off the stud at all to get to the nut if that makes any sense. I'm about to get destructive with this dam thing. Last night I just fully assembled the manifold injectors wiring harness and tps rigged connector so literaly when I get this old one off it will take all of 20 minutes to get the car up and running and get some good info for everyone.

 

[GS-T_Newboost]

the black box is mounted on the two braces it a called a vaccume box used for cruise control if u deleat it your just not going to have cruise control.

 

[Slippi84]

the black box is mounted on the two braces it a called a vaccume box used for cruise control if u deleat it your just not going to have cruise control.

I'm gonna open up a can of woop ass on the vaccume box and throw it out while i'm "cruising" onthe high way. I just got my prothane mounts pre-installed with mounts today so I'm gonna use this time to do everything I been meaning to do anyway ,like take the head off and clean it and put in new valve seals cause this thing burns oil right now. So the performance update will have to wait but I'm gonna get some pictures of the manifold and tb when I get home for everyone.

 

[Blitzeclips]

Pics and dyno sheets would PWN.

If the results are good, I'm paying you and Corey a nice visit when I come pick up that extra OBX you have!

 

[Slippi84]

Pics and dyno sheets would PWN.

If the results are good, I'm paying you and Corey a nice visit when I come pick up that extra OBX you have!

WHose corey? Yeah I almost forgot about that extra obx manifold. I won't have any baseline numbers but i figured I have such basic mods people should be able to get an idea of the gains or lack there of . The head is getting a 3 angle valve job and if I can squeez it out I have a line on some stage 2 crowers that I"m gonna put in.