I just noticed this, and can't tell if my auto 2k3 has always done this or if it's new since the RSB / FSTB (don't see how that's possible). If I leave a stop at one-third throttle or less, the car rolls of smoothly. But if I go harder, there's a slight "thump" sensation after about a quarter second. Is this the torque converter locking in? I tried it with the brakes on to make the sure transmission wasn't slipping, and it did the same exact thing (slight thump then started straining the brakes).

Think I'm paranoid, but can other 2k2 / 2k3 auto owners jump in and make me feel better (or worse, I guess)?

Thx

 

I have a 2K1 and it's a Manual transmission.

1)What FSTB do you have? It's MOST LIKELY your engine hitting the FSTB. The engine moves a lot under initial take off and reverse, so it will hit the FSTB if it's not properly installed or the correct one for your car.

2)It could also be your POS jello motor mounts allowing the engine to flop around and you're feeling the drivetrain lash. However, IF your a jack rabbit stop light driver or have gone to the track, you may have busted one or more of your motor mounts. The clunk could be the engine shifting, since the mount is unable to hold the engine.


You should see the shifter on my car hop around, especially if I let off the gas pedal completely and then touch it again no matter how softly. I don't think I've broken a motor mount yet, but the rear mount supposedly breaks all the time if you launch hard.

We need aftermarket motor mounts that are stiffer than the OEM, but not as stiff as the poly Place Racing mounts. Some people are making ghetto mounts, but you'll need a donor pair.

My .02, which isn't worth jack!

 

Good input - thanks! I think it's the FSTB, as I doubt I've done anything that would kill a motor mount. I'm also getting a weird grinding / scraping sensation in reverse now, so I'm going to adjust the FSTB, and if that doesn't work just take it off. Seems like the main benefit comes from the RSB anyway.

 

What FSTB do you have?

If it's a cheapy then I'd bet it's that, but you might ask people who have that particular bar, what they did to modify it.

 

I noticed this the last time I had my Max out. It only has 650 miles on it and I haven't had it a WOT yet. I thought it was just my imagination until I read your post. I'll pay more attention to it next time I drive and report back.

 

The same thing hapens to me in my 2k2 6 speed, but I dont have a ftsb I also noticed a loss in power when accelerating frm a dead stop.

 

I have this on my 2000 SE AT. I have no FSTB either. No suspension mods. A set of Maxspeeds have been sitting in my closet for about four months now!

Anyway, to describe it... under WOT or heavy throttle, even when the car is warmed up, there is a *thunk* sound coming from what seems to be the engine bay. It's as if the engine is actually loose, not bolted down completely or something.

Have 2 years of bumps in the road loosened things?

 

My 2K2 does the same thing. If you find out what it is let me know. I took mine to the dealer and they said this is normal, yea right!

You can put it in D, put the brake on and give it throttle and you will feel this thump without even taking off.

 

This is just a guess, but when you put the car in D, and give it gas, the engine moves around a little, so perhaps it's a little loose in the bay and is banging against something. I'd def make the dealer look at it and complain--no way it's normal unless EVERYONE on this board can attest to this.

Keep us updated.

 

Have someone get in the car, put it in D, and put their foot on the brake. You, open the hood, stand BESIDE the car, have them rev it, and watch to see if the manifold is hitting the FSTB. A lot of people were complaining about just that in an earlier thread. I have the CustomMaxima FSTB, and it clears everything by quite a bit.

 

Update - it's not the FSTB, 'cuz I took that off completely and same problem. Hmmmm...

 

Final update on this. I took my car to the dealer: they checked the tranny and the motor mounts, and made sure nothing was loose. They also checked the suspension (surprisingly, saying nothing about the RSB ), ditto. The tech said that it was normal, and they (helpfully) brought me a brand-new 2k3 to test drive and see if it felt the same. This one had 13 miles on it, and the feeling was a little different but there (sort of a combination of the weird 2k3 hesitation when new plus the "thud"). So I'm at least convinced to the point that I'm not going to do anything else. If there IS a tranny problem, it should fail before 36k miles.

I also had an Altima loaner while they had my car. No offense to Altima owners (hey, it's a question of what you want), but the 2.5 Altimas always feel like go-karts to me - I always find myself winding out the engine and throwing it around like it's a toy. Actually kinda fun (except for the acceleration ).

 

Sounds about right.

I'm betting it's just the jello motor mounts allowing the engine/tranny to shift....making a thud.

Upgraded mounts may be the answer down the road. Plus, it will help with wheel hop, if that's a concern.