Try videotaping it from multiple angles.

 

Our 07 did this at every cold startup. If I just sarted it and let it idle for 3-4 minutes then shift it into R there would be no clunk, but starting it up cold and letting it idle for 30 secs or less it would have the abrupt clunk into R.
Our new 09 G has not had this issue, maybe it's the new 7spd auto or they did some software patch or tranny tweak??

Since the OP said this problem is getting worse that would raise a flag, but otherwise I would say the cold-start clunk is pretty typical in pre 09 Gs.

 

What occurs if you shift directly into neutral and then drive not stopping at reverse? What occurs if you go to neutral and then back into reverse?

I would have to see if this car has a parking claw. I have seen something like this on older cars where the parking claw would hang up a little until the car has moved.

You may want to consider flushing the transmission fluid, especially if you happen to purchase this used.

 

Take it to the dealer, let them keep it there over night and drive it come morning. Thats what loaner cars are for.

 

Take the car to the dealership. explain what is happening, ask for them to keep it overnight and see if they can duplicate it in the morning. It would be best if they left the car outside. The transmission MAY be low on fluid, although I do not think this is likely, it sounds like a switch or other electronic unit has failed.

There may be a TSB on this issue. Rest assured that unless you are racing the car or are reallly beating it up that the possibility that your mods are causing this problem is unlikely.

 

Is your car lowered? How much camber?

 

not trying to be funny but do you hear a click? My car was doing that but it was just the rear axle (see the TSB on it). Mine got so bad that when I shifted into park/drive/reverse it did it.

 

My car is lowered on H&R's.. I am guessing around 1.8 inch up front and about 1.6 in the rear. Not slammed but lower than most drops I've seen from springs.

I am currently running -1.2 in the rears and approximately -1.6~1.8 up front in camber.

Why do you ask if you don't mind me asking??

 

I do hear a slight clicking at start up sometimes. But it's not severe and it seems to only happen occasionally and goes away pretty soon once the car is warmed up.

 

IMO I don't think it's possible to capture this "jerk" on video.

 

This may not be an issue with this car but on some when you lower a car you are changing the angle of the half shafts from the differential to the wheels on a non floating differential typical of independant rear suspensions. This can change many factors of how the power is delivered to the wheels and how it feels. It can also change how the parts wear in this regard.

My other car is a fwd and on it when you lower the car you also have to follow with the engine/transmission to maintain this angle.

 

Interesting.. definitely appreciate the feedback. It seems as if there are too many possibilities to diagnose this problem I am experiencing. Maybe I am just better off taking it to the dealership.

Do you think I should uninstall the intake and reinstall the stock before I do? Man the Gen 3 install was a real PITA. I would hate to have to take that thing off................

 

The problem with the intake I can see is it being a flag that gets noted. Doesn't matter if it really had anything to do with an issue. Even doesn't matter if the car is fixed without a problem by a particular dealer. It will probably be noted on your car. So in that regard it comes down to just how a particular dealer treats it. I mentioned it earlier since I know the difference between how much effort this intake takes to install compared to some others.

But then the other issue really is the lowering job. For something like a transmission issue I would consider this of greater importance and from what I see you may just have to bite the bullet if you take it into a dealer. You may want to see if there is a mod friendly dealer in your area and go there. At least he may be able to tell you if there will be any warranty issues with a particular mod. Just keep in mind that mods do create a risk for warranty repairs. I agree with a dealer who in some cases refuses to fix something under warranty due to what mods are present. In other cases I don't.

In your case for example I know of the issue with how lowering affects my other car in regard to all sorts of issue due to the change in angle of the half shafts without the engine/transmission spacer kit. If a similar issue is present in various Infiniti models then I would agree with the dealer refusal. However if there are no issues in this regard then I would not. You may want to research this to see if there are reported issues between a lowered Infiniti, half shaft wrapup causing transmission problems before pressing a dealer into action, one that you just may not like.

In your case it may well be that the transmission really isn't the source of your reported jerk, it may well be half shaft related and an easy fix, something you may want to consider by first taking it to a non Nissan repair shop.

 

I think I will take my car to Riverside Infiniti soon. I heard they are pretty mod-friendly..
Also to be safe, I will contact the service advisor first to make sure that they won't flag my car in anyway because of the aftermarket parts. I don't think they can deny any warranty service because of an intake or any other bolt on unless they can prove that particular aftermarket part lead to the problem.

Thanks for the input.

 

Only partly true. It comes down to what is stated in the warranty and how it ends up in arbitration. Remember that in reality you have to prove that it could not lead to the problem at hand since the dealer already denied the work. In court you may be up against a judge that looks at what mods you have on your car and agrees automatically with the dealer.

One really needs to read the actual act in this regard and what the intent was.

One intent was to enable you to see the warranty prior to purchase. Another intent was to allow the use of non-oem parts which are equivalent. For example oil and oil filters that meet the OEM requirements.