MUST READ: How to turn a new Infiniti Q45 into an E55

[Jason B]

Dear 001,

For a car with 340 horsepower and 333 foot-pounds of torque, you would think that the new Infiniti Q45 would be "snappier" than it is. The ads claimed 0-60 in 5.9, but that must have been downhill. In a hurricane. The car didn't "feel" that fast. Quick, but not fast.

At least that's how I felt before I took my car into the Infiniti dealership for a software reprogram. It seems that everything electronic is getting updated these days. You buy a new piece of software for your computer, and there's a patch out the very next week. You buy a new digital camera, and the manufacturer has an "upgrade" with new features for you to download off of their Web site. With a car as technically complex as the Infiniti Q45, a software "upgrade" didn't surprise me.

What surprised me was that this upgrade wasn't for a new radio or navigation feature. It was to give the car more muscle. And oh boy, did it work.

Infiniti calls it the ITB-02048 update. The first part of the fix replaces the accelerator pedal with one with a bit less lag in the pedal itself. Nice update. Good update. The second part of the update doesn't involve any new parts - it is all ones and zeros, but it's what makes the big difference.

It reprograms the Engine Control Module. Shifting and acceleration are totally different. Night and day difference. The car shifts like the little G35. It's gone from Oldsmobile shifting (no offense) to German shifting, and from a stop the car feels so much faster.

The Infiniti service manager says the reprogram changes shift points, spark firing timing, and fuel injection timing. For marketing's sake, I can't believe that Infiniti isn't promoting this update more, as it would make all current-generation Q45 owners very happy and also get the media to take a look at the car once again. And thankfully, for Infiniti's sake, it's a very nice improvement.

FULL ARTICLE on AutoSpies - http://www.imakenews.com/autospies/e_ar ... s3,aNvhT3N

I emailed AutoSpies about this fix and they were interested in having a write-up made. A big thanks to forum member ADAM CB for taking the time to make this article so good. He has since done this upgrade as well. As you can see from the comments above, it's worth it 100%.

[maxnix]

Infiniti calls it the ITB-02048 update. The first part of the fix replaces the accelerator pedal with one with a bit less lag in the pedal itself. Nice update. Good update.

One of the updates I downloaded for 2002 Q45 built before July 4, 2001, (or before JNKBF01A*2M006185) showed the original throttle pedal pivoted at the bottom of the throttle link, with the upper end of the pedal damped by a spring.

Obviously, one unaware of this configuration could tip in the throttle with the toe of the right foot, but just be moving the pedal by compressing this spring, and not moving the throttle rod significantly. The update eliminated the spring and pivot point so that the pedal is hard mounted on the throttle lever. Any movement of the pedal moves the throttle lever after the update.

I wonder how many of the early accelerator problem reports are due to this arrangement, and the owner's not realizing that the first few inces of throttle tip-in may have only been pivoting the throttle pedal until the slack was gone before the actual throttle lever moved?

Do you know if this was an issue for your 2002 Q45, Jason?

[Jesda]

Interestingly, on many MB cars, the throttle is in two stages. You hit the pedal expecting to lunge forward, but it barely creeps ahead. You have to push the pedal in further (feels like its stuck) and it requires you to REALLY push each time to get going.

Takes forever to get used to. Annoying as hell.

-Jesda

[PalmerWMD]

Great info!Thanks Jason!

Fred..

[don85259]

I'd like to see some real world results, like dyno numbers and 0-60 times as measured by someone reputable (say Motor Trend or something). If this can be done for the current Q45, I wonder if something like this could be done with my 1998 second gen Q45?



--don

[yidal8]

can this update be applied also to the M45 ( the software part) or is it already built in ?

[Blayne Olsen]

Will anyof this apply to my 2001 Q45t and is there an site to find all the updates that apply to my car

[maxnix]

2002 - present Q45 engine (US) VK45DE1997 - 2001 Q45 engine (US) VH41DE
Modified by maxnix at 6:43 PM 1/5/2005

[Jason B]

Do you know if this was an issue for your 2002 Q45, Jason?

Yes, it was just about on every 2002 made. I had this done when I first got the car, and the 2nd one done for the ECU/TCM a short time ago. Infiniti now does both at the same time under one service bulletin now.

It's a night and day difference!

The transmission/ecu upgrade is amazing! The car feels so much quicker! It takes off instantly from a stop as well. Also, say at 30mph when you mash it, it really goes now and grabs the road behind you pulling you back into the seat. The shifting is much smoother and crisper than before and it's MUCH more fun to drive. It feels like it was given steroids. I'm a very anal person with vehicles and notice everything and this made a big change to me. The new TCM/ECU work ran about $1,200, but again, under warranty since it’s an ITB/TSB!

[PalmerWMD]

can this update be applied also to the M45 ( the software part) or is it already built in ?

M45 is a 2k3 all 2k3 is IAW TSB from factory.

Fred..

[Spinmaster]

My service guy in Miami says he doesn't do it because it "voids the warranty". Is this true?

[Jason B]

My service guy in Miami says he doesn't do it because it "voids the warranty". Is this true?

No, he is just being lazy. It's a service bulletin, service bulletins don't void your warranty. With an attitude like his, I could call another dealer.

[yidal8]

So that mostly explain the better acceleration performance of the M , compared to the 02Q , since it is only 100 lbs. lighter . The 03Q also has the same diff. gear ratio . Is the 03 Q & M performance basically the same ?The best 0-60mph I have seen for the M was 5.7 sec.

[Jason B]

Yes, they should be about the same.

Now can can start claiming what they said in the beginning...

Save and open this file....

http://www.burtmanindustries.com/q45/Infiniti.exe - Right click and save this - 700 kb

[Spinmaster]

Thanks Jason. Time kick some butt

[AZhitman]

Jason, have you considered a letter to the Editor of Motor Trend or C&D?

This needs to be more common knowledge.

[yidal8]

What are actually the best 0-60 numbers reported in the mags for the M or Q ?

[Blayne Olsen]

I just got back from my dealer and I think he brushed me off telling me this didn't apply to my car. Can anyone on this thread tell me the truth? VIN JNKBY31A31M 101374 This is a 2001 Q45t.

[Jason B]

This is only for NEW model Q's. 2002+

[Q45tech]

Even with the new diff gear the ratios in the transmission are still wrong IN SPREAD to perfectly optimize the zero to 60 and quarter mile times plus the 55-80 mph range. The shifts should occur at 63mph and 100mph...........just like the LS430 does. Unfortunately the JATCO high ratio overdrive gear runs into problems with anything other than the V6..........too many revs at highway cruise but perfect for a V6 requirement that needs to turn 300 rpm more than a V8

The transmission gears were selected to match the G35car/ motor [which came out late] and to provide lux in a V8 car.

Saving money by having one geared transmission to fit 2 engines and 7 cars............means somebody loses.

[yidal8]

0-60 @5.7sec. (if I'm right) is pretty impressive .But it is a shame that they can not back-up the best V-8 in the business by a top notch drivetrain .

[PalmerWMD]

That drivetrain is vey good.Just not perfectly matched to produce 0-60 and 1/4 mile times for the magazines.

Fred...

[90Q45blue]

Still, this update would change of lot of people's opinions, buyers and experts alike, on this car.

Nick

p.s. i agree w/ hitman, C&D and R&T need to know about this.

[yidal8]

Fred , Reliability wise at least ,the jury is still out . The new transmission is sealed , so we are not suppose to flush . We know our beloved 1gen. Q need some extra TLC regarding the transmission.

[Jason B]

New Q45 engine and transmission:





More pics on my website:

http://get.to/q45

[maxnix]

That drivetrain is vey good.Just not perfectly matched to produce 0-60 and 1/4 mile times for the magazines. - Fred...

These times are irrelevant unless you are sanctioned drag racing or publishing.

The 50 - 90 time is much more relevant for highway operation.
Modified by maxnix at 6:44 PM 1/5/2005

[G8R45]

I had the gas pedal changed a couple of months ago. The Q is going in this coming Tuesday for it's 15000 service. They are scheduled to also perform this upgrade. Seeing as how I traded a 2000 E55 for this car I am really looking forward to the improvement.

[nuQ]

wondering that same thing......what are the benefits/drawbacks to having a sealed trans????jeff

[SonzofGod]

Does anyone know anymore info on this? I called the an Infiniti Dealer close to me and the service guy didnt know a whole lot and couldnt tell me whether the update ITB 02048 had been done....

so I thought I might be able to tell by looking behind the pedal?

I also called Infiniti directly and the person I talked to said they didnt have information regarding Technical Service Bulletins....I thinking, OK then who does?

Looking forward to the upgrade if it is for real....please reply

Thanks,Nicknew 02 q45 owner

[Jason B]

If the dealer wants to hellp you they can tell EVERYTHING that has been done to your car by looking up our Vin #. Your dealer will have all the bulletins on file and should be able to tell you the latest updates.