G35Rhino

Had the TSB done on July 3. My impressions after almost 3 weeks of driving and 2x 300+ mi roadtrips (again these are MY impressions and not speaking for the collective):

*rough downshift fixed;
*smooth shifting through all grears in all modes (silky smooth)
*serious bouts of either throttle lag or shift lag which I had not noticed before TSB
*decreased gas mileage (~1.2 mpg average)

The mileage issue I can live with as I still get better than 27 on the interstate and ~22 combined driving but clearly I've given up some mileage by (here's my assumption) leaving the throttle open slightly to smooth out the downshifts and reduce engine breaking issues.

However the throttle lag and/or shift lag concerns me greatly and is new for me since the reprog. I have noticed it 3 times. The first I was being cute and floored it from a 3 - 5 mph rolling start and the car did not respond at all (it felt like it was in 3rd gear or something) rather it just slowly climbed up to speed for a couple of seconds before dropping down into the right gear and taking off like a bat out of hell. It was a bit embarassing as it sounded like the car was flooding out before it kicked into lower gear. The other 2 times were when I was crusing the interstate and gave the car considerable gas to pull out and pass...again the car didn't downshift rather it felt like it "missed" even though the engine was purring smoothly and then finally started picking up speed gradually before dropping a couple of gears and taking off. That's a good way to get yourself killed at 75 mph.

Am I the only one with this problem since the reprog? I can't tell if it is a throttle response issue or if it a transmission shift issue and unfortunately cannot duplicate the problem at will. It just kind of happens and now I spend more time looking for it to happen and less time enjoying the ride.

One final comment, my service documents do not mention an ECM program rather just the TCM re-program. You would think they would document something like that. I have heard people say it was prerequisite and others make no mention of it (like my dealer). The TSB makes no mention of an ECM re-program either.

texashoser

I've noticed the throttle lag issue before *and* after the transmission software update. All I can do is assume they'll eventually figure this out and issue an update that fixes the problem; or replace the transmission.

KLB

I never noticed it, but in the situations you mention I am usually in DS rather than D.

Black Betty

iTrader: (60)

[shameless plug] By installing a Betty's Garage grounding wire set you will eliminate most of your throttle and shift lag issues quite easily and for a very reasonable price. True story. [/shameless plug]

Alex57r

my car never had such issues, but judging from other cars ihave had in the past, it is sometimes possible for the transmission to get confused and think that a downshift is unwarranted. If it happens VERY rarely i would not worry about it. I actually like to tap the left paddle before I start to pass another car etc. If the problem persists though, it could be an issue. Keep us posted on what happens.

sneather

What exactly is a grounding wire going to do for the transmission? In fact, why do I read about people installing such, at all???

DJ Hellfire

I agree. I personally never understood the usefulness of a grounding kit. When you think about the laws of electricity, current always chooses the shortest path to ground, not multiple paths. With that said, the engines electronics are probably still going to ground through the main block ground anyway, since it will most likely be the path with the least resistance. Just like multi prong spark plugs. They do nothing for performance since spark only goes through the prong with the least resistance, not all prongs. The only thing they are good for is duration because if one prong starts to wear, you still have 2-4 back ups. So I personally think grounding kits are useless. But I am just going off theory, not experience with them!

Mike S.

For my .02, the downshifts are much nicer now when comming to a stop.

I noticed no reall difference in upshifts or throttle lag? Due to the reworking of the torqure converter locking on downshifts (I think thats part of the fix), the car might be less responsive to hitting the gas as your comming to a stop (since you don't have the responsiveness of a locked torque converter), but I don't think the fash did ANYTHING to the throttle/ecu.

G35Rhino

I had a similar issue with an Acura CL Type S several years ago -> confusing the transmission and not knowing what gear to be in. The tranny went out on it with less than 25k and the replacement did same until I traded it in shortly after the fact. I do not think that will happen in this case as the tranny feels much more "substantial" than the Acura's but who knows......

G35Rhino

Thanks for the reply. It is possible it was happening before the flash but I did not notice due to the herky jerky nature of the up/downshifting issues pre-flash.

The good news...it doesn't happen often. The bad news...it shouldn't happen at all. Such is life I guess....

Black Betty

iTrader: (60)

That's what I thought. I've noticed that almost every single person who thinks this has figured out that it won't do anything to help their car from their extensive knowledge of electrical engineering and not through actual practice. I used to be quite uninformed myself until I had an issue in an older car that I threw about a grand at trying to get diagnosed and fixed. Then I followed some advice I'd gotten and did some grounding and got improvement. I tinkered even more and eventually solved the problem completely through supplemental grounding.

You stated
This is almost true. The path that electrical energy will take is the path with the least resistance but that is not necessarily always the shortest distance. A 6" long titanium wire has far less current carrying capacity than a 12" long wire made of silver or even copper. A 6" long 10 AWG copper wire has more resistance than a 12" long 0 AWG copper wire.

No multiple paths to ground, huh? If a given source has two or more paths with equal resistance, the electricity will just pick one path and use only that one, ignoring the other paths that have the same resistance??

That being said, do you have any idea whatsoever how you car is grounded anywhere other than the negative battery/chassis ground? I do.

I am NOT saying that grounding wires will fix everything electrical that may be wrong in a car, that would be untrue. I am NOT saying that grounding wires will give you mad horsepower, yo. I am saying that it will help a lot of things that many people may theorize that they cannot effect.

DJ Hellfire

1. By shortest, I was referring to resistance, which I stated in the example of the multi-prong spark plugs! My bad for the wrong word!

2. True, but typically speaking, how often will a componet have two ground paths with the same EXACT resistance in an automobile? If I had to guess, I'd say each of those ground wires in a kit aren't that precise. I was saying that if the engines main block ground has less resistance than any wire in that kit, then isn't the kit useless?

3. Yes. But that all leads to the battery through the chasis! I don't get the point of this question. Current from an amp grounded in the trunk isn't going to go through the chasis through a grounding kit then back to the chasis to the battery. The only point I see for an ENGINE grounding kit is for electronics grounded to the engine, like an alternator or some sensors. If the wires in that kit are any better than the block ground, then I can see a benefit. But then what's the point of multiple wires when you can just upgrade the main one?

4. If you have electrical issues that a grounding kit fixes or helps, then you are just patching the issue, not fixing it (unless your issue is due to aftermarket accessories drawing excess current, like amps).

And before this goes south, I am in no way being a **** or starting a fight. This is just one educated man having an adult discussion with another. I know how forums can get!

Black Betty

iTrader: (60)

I fully understand what you are saying DJ and I am of the same mind. I can certainly appreciate your being able to disagree based on facts and your personal experience while being civil and respectful. I don't think you came across the wrong way, at least not to me.

The block's factory grounding isn't more efficient than the ground wires I make. For me the point of redundant engine grounding is that the ground on each side of the engine is there to provide a path of lesser resistance on either side, the electrons are smart enough to take the correct one for greatest efficiency. I wholeheartedly agree that if you have a real electrical problem that better grounding won't cure it, only possibly treat the symptoms, that and you need to get it diagnosed and corrected.

DJ Hellfire

I hear you! I hate diagnosing electrical ****! Sometimes it's fun, but most times I'd rather not be bothered.

Mockenrue

I agree with those that said the throttle lag was present before and after the updates. I've noticed it mostly when hitting the gas after a "rolling stop". If you go from a dead stop, or are moving along, the response is great. If you are nearing a stop, there is a short delay before it kicks in.

I actually think it improved in my case. Prior to the "flare fix", there was a short lag followed by a rough down shift from a rolling stop at certain stop signs. After the fix, the lag is still there, but no more "clunk" shift.