Tranny issue

[OneBADLsE]

***THIS IS A REPOST. I HAD POSTED IN THE WRONG FORUM BEFORE, NOW I BROUGHT IT HERE. SORRY TO ANYONE WHO HAS READ IT BEFORE***



I have started to notice in recent weeks that my car has lost some power. A very weird thing that i notice is that under WOT at around 45 i feel a ''shift'' ( i think this is lockup) and it normally happens at around 40-60 where as around 55-70 it would really come alive on WOT. Now, it only feels marginal the power.

Im thinking either the lockup schedule (tune) is really out of wack, or something else electrically is going on. OD lockup in the morning takes around 4-6 miles to actually engage. Also, under WOT, you can feel the power coming on and letting off almost like a hesitation, but its not... Do i make any sense to anyone? LOL.

Something tells me i might be visiting Sal a little bit sooner than expected.

FYI : This is a 2002 GM LSE :D



Ah, i forgot to add that when driving on light throttle i used to have lots of torque on demand without kicking it down between the speeds of 55-80. Again, that power only feels marginal. When driving again sometimes under light throttle, i will also feel a brief "buck" - No clue where that comes from on occasion.

[magindat]

Not a joke....

Clean/change your air filter.

[OneBADLsE]

Not a joke....

Clean/change your air filter.


I'll give it a shot i suppose?

[OneBADLsE]

How many miles and when was the last time you had the trans fluid replaced?

Tranny was rebuilt at 23k due to my feeling that the shifting patterns were wrong and sloppy

[RF Overlord]

OD lockup in the morning takes around 4-6 miles to actually engage. That is normal operation...TCC won't engage until the ATF is warmed up slightly.
...under WOT, you can feel the power coming on and letting off almost like a hesitation, but its not... Do i make any sense to anyone? LOL.Actually, you do make sense... ;) Unfortunately, there are a lot of things that can cause symptoms that sound very similar to yours: A/F too lean (vacuum leak) or an ignition miss (bad COP, boot, or plug) are 2 I can think of offhand...get to an AutoZone or similar and get the codes read...sometimes a slight misfire won't light the CEL, but there could be stored codes.

[OneBADLsE]

That is normal operation...TCC won't engage until the ATF is warmed up slightly.Actually, you do make sense... ;) Unfortunately, there are a lot of things that can cause symptoms that sound very similar to yours: A/F too lean (vacuum leak) or an ignition miss (bad COP, boot, or plug) are 2 I can think of offhand...get to an AutoZone or similar and get the codes read...sometimes a slight misfire won't light the CEL, but there could be stored codes.


speaking of which, intermitantly i will have a no start condition (albeit brief) randomly. i will get thoes stored codes read asap. Very helpful advice, thank you:coolman:

[MENINBLK]

Im thinking either the lockup s[FONT=Arial]chedule (tune) is really out of wack, or something else electrically is going on. OD lockup in the morning takes around 4-6 miles to actually engage.

Torque Converter Lockup doesn't occur until the ECM goes into CLOSED LOOP.
There are lots of variables that allow this to happpen.
The MOST important is COOLANT TEMPERATURE.
This won't happen until your engine warms up at a minimum.

After the ECM has achieved CLOSED LOOP, TC Lockup occurs at a variable rate
according to all of the inputs to the ECM. It just doesn't turn on and off.
It is a gradual lock and unlock just like a clutch.

[Stranger in the Black Sedan]

The shift points are fully electronic, so shift timing is probably not your transmission. If its shifting too soon/late it is probably ecu/sensors/servos that I am not even qualified to guess at.