Found 10 HP Infiniti left behind

[gwoods]

I spent 2 hours on Sunday changing out spark plugs on the G.

To get to #6 and #5 you must remove the throttle bodies. Common practice on a 50 state car is to have an electronic heater on the throttle body. This lets the car operate in very cold climates.

On the Hemi Ram I put a resistor in this wire cause I live in Phoenix and the air is hot enough. The infiniti has two 1/2 diameter rubber hoses going into the throttle bodies. The throttle bodies are heated using antifreeze piping hot right out of the block!

I think that it is possible to disconnect the hoses and just make a loop so they don't go into the Throttle body any longer. The intake air should be cooler as a result and horse power should increase across the board.

My question to any tech's... will the ECU detect that the throttle body is no longer heated and light up my dash?

I'm doing all the hoses under the hood come March and flushing the coolant. I will likely try this mod then.

[G_whizz]

Steve is away for a bit on a trip...not sure if Poyzy knows, but if he doesn't he'll ask.

[smockers83]

Well, there is the throttle bypass mod that has been out there for quite some time now doing this very thing.

[zozoka1212]

Jeff

bypass is an easy way to get few extra ponies. You can also make it cold weather proof too. Al you have to do is install a valve in it and when it turns cold just switch back. I know it is getting really cold in AZ. LOL Joking put aside I think TB is the cheapest mod.

[kmckis1029]

the Mortordyne people actually sell the TB coolant bypass with their isothermal spacers. They will sell you the valve seperately...

[tollboothwilley]

Common thing Jeff. People have been doing this on the G for a long time now. You must have been away for a while!

[joe603]

I've done it to my G...I usually turn off the bypass in the winter months. No problems what-so-ever.

[BrandAidDesignG35]

Sweet! I recall a DIY on this somewhere...

What temp do you usually turn off the bypass?

[Poyzinous]

NO! do not disconnect/bypass them. The older VQ motors did not use coolant, but the new ones use them to regulate temperature and idle control. Don't disconnect if you don't want codes. The throttle body needs to operate within certain ranges. If it doesn't need coolant, the car will adjust and bypass itself. Besides, do you know how fast air is flowing past the throttle? from the point of intake at the front of the car to the intake valve, air goes through all that in 1.0 to .01 seconds depending on vehicle speed and engine speed. Yes, the air temp will be one half degree cooler on a 100* day at 750rpm idle speed, but again, no. Leave it be. Its not the same as other cars with mechanical throttles. You guys with an older VQ motor, there is a vaccum line but what coolant line are you playing with?

[gwoods]

That was what my curiosity was about, not so much if I could do it but would I have to deal with CEL's.

I will leave it alone.

[joe603]

I've had it bypassed for a few years now and never got any codes...

I usually un-bypass when the first frost hits.

[tollboothwilley]

NO! do not disconnect/bypass them. The older VQ motors did not use coolant, but the new ones use them to regulate temperature and idle control. Don't disconnect if you don't want codes. The throttle body needs to operate within certain ranges. If it doesn't need coolant, the car will adjust and bypass itself. Besides, do you know how fast air is flowing past the throttle? from the point of intake at the front of the car to the intake valve, air goes through all that in 1.0 to .01 seconds depending on vehicle speed and engine speed. Yes, the air temp will be one half degree cooler on a 100* day at 750rpm idle speed, but again, no. Leave it be. Its not the same as other cars with mechanical throttles. You guys with an older VQ motor, there is a vaccum line but what coolant line are you playing with?

When you say "older VQ" motors, what are you referring to?

All the G35's I've seen have coolant passing through the throttle bodies, including mine (early 2003)

[Poyzinous]

Theres coolant running through the manifold, but not the throttle chamber itself. Theres just a vaccum line there behind it. The coolant lines run under it for temp purposes.Here John, I'll give you some illustrations, cuz I'm awesome like that. This is your throttle body, on the VQ35DE motor (except QX4/pathys) This is an illustration of the coolant lines, note there is no throttle body in the pic.... but look at the V36 model G35/G37 motor in the next pic Notice the throttle bodies have coolant lines running through them The newer Second gen VQ motors use coolant the way old school motors use them, but remember that they were done that way for a reason. The engineers did it because they had to have them there. The Vaccum line I speak of bedind the throttle is this one here: see what I mean? thats just an emissions related line, blocking that off would cause a service engine soon light to come on.