New Firebird owner Q

[mousemonster1232]

So I just purchased my 2000 Firebird a few days ago.

My car just before this one was a 99 Pontiac Grand Prix GTP. It had the 3.8L V6 Supercharged.

So I am familiar with the engine (for the most part).


Now after a few days of driving and noticing things...
I have found something I want to verify.

When I am driving, like crusing around 45 miles per hour, the car is going at about 1500 RPM (+/- 100). Every few seconds it will raise up about 200-300 RPM and then drop back down to the idle RPM.

So I took my ScanTools scanner to check out the TC and transmission, and it said it was all in working order. So I figured it was the O/D. So I thought if I were to put the shifter down into 3 it would fix it. But it does not.

The only difference is when I put have it in drive instead of 3, I get more RPM slippage. (500 vs 50)


Any ideas on what the issue is? Or maybe it is common and I do not have this knowledge.

Thanks.

[ACiFiC]

Re: New Firebird owner Q

welcome! you should throw up a few pictures of the bird. looks like this is an automatic... whats your transmission fluid level at?

[mousemonster1232]

Re: New Firebird owner Q

Thank you. :) I can put some pictures up in the morning, it is so dark already! It's horrible! haha.

Yes, it is an automatic, and according to the dipstick, it is in the correct level. Right about in the middle.

[FirebirdGT]

Re: New Firebird owner Q

Another AZ F-body owner!! Welcome.

:banana:
.

[flamingchicken]

Re: New Firebird owner Q

Honestly is sounds like the symptoms leading to a TCC valve failure. That is what mine did, the torque converter would unlock for a couple seconds, then lock back up, hence the change in RPM. There is a GM tech bulletin on it. Have you been on a long interstate drive in it, like more than an hour? If so did it shift hard upon comming off the interstate? That is a sure sign that it is your TCC valve.

[mousemonster1232]

Re: New Firebird owner Q

I just purchased it on the 1st so I really have not been on any long drives with it. It seemed all fine when I purchased it. The longest drive so far is about an hour and fifteen minutes. Before, during, and after that drive it shifts quite smoothly. Especially smooth compared to my previous car (99 GTP) but that could be because it was modded and had tuned PCM with tighter shifting points.

And it only has 112k miles on it.

[mousemonster1232]

Re: New Firebird owner Q

Also, thank you FirebirdGT. :)

[madmike3.8II]

Re: New Firebird owner Q

Dunno if it's any help, but I had a 97 camaro that did the same thing, but I noticed it was just the shift point into OD. I thought it was the torque converter having troubles locking up, but I never had any issues with it, just got better gas mileage around 45mph when it would shift into OD. Now I have a 2000 camaro, and it's weird it will shift into OD as you are approaching 45mph (not quite 43/42mph), and actually stay in OD until you drop below 40mph. I can't think of a logical explanation of why that is, since they're the same motor correct?
Anyway, Congrats on your purchase!
I think you'll find that these cars are fun and very dependable if ya treat 'em right!

[mousemonster1232]

Re: New Firebird owner Q

madmike, I think we have the same issue. Maybe it is just perhaps the shift point of the transmission because like I stated above, I checked it out with my Scantools scanner for the TC lockup and tranny, and it was all good.

[flamingchicken]

Re: New Firebird owner Q

take it on a good long drive sometime, and see if you get the hard 1-2 shift.

[97RSSM90]

Re: New Firebird owner Q

welcome

[mousemonster1232]

Re: New Firebird owner Q

Thank you, 97RSSM90.

And today, I went on about a 2.5 hr cruise. (coincidence or not... Who knows? Ha) And it felt as though the first to second shift was a little bit tighter, but nothing TOO horrible. It just felt as though it was a little whiplash-ee-er? Haha I don't know how else I can explain it in layman's terms.

[flamingchicken]

Re: New Firebird owner Q

http://www.obdii.com/ubb/Forum1/HTML/003177.html

That has the TSB from gm on the 4l60e tcc problem.

For me it got to the point where the 1-2 shift almost barked the back tires it was so hard, and only when my car refused to shift into OD did I actually do something about it. In the beginning it was just a firmer shift, then as time went on it got worse. When I first noticed the symptoms it was when I ran open headers for about 2 weeks, I could hear the engine changing just like you stated, up 200-400 rpms, then back down, I just thought it was normal, and didn't connect the two together. Luckily, I had the TCC update done for about $600, not too bad, less than a transmission cost.

Edit-now would also be a good time to see if you have the P1870 code.

[mousemonster1232]

Oh yeah. Definitely isn't that bad. Its just a tighter shift. And there are no codes or lights illuminated either. So I suppose I will just keep an eye out on it.

Sent from my Samsung Fascinate using Tapatalk.

[mousemonster1232]

I really appreciate the help from everyone. This will be a good forum. They're getting rare.

Sent from my Samsung Fascinate using Tapatalk.