different hesitation problem

[murr2424]

i drive a 96 4-clinder automatic. the first and sometimes the second and third time i try to accelerate, the car sputters and hesitates. then after that, it won't hesitate on take off. however, when it switches from 1st to second gear, the car lurches forward after 2nd gear engages. also, when i'm going up a hill, the car hesitates and catches, hesitates and catches....as if it can't decide whether it wants to downshift or not. the result is a loss in speed and power. i have to stomp on the accelerator to get it to downshift properly. where should i start with my diagnostics? anyone have suggestions? i'm thinking fuel filter, transmission fluid/filter change out....

[rixGAphx]

How many mles total on the car?

The Check Engine Light isn't 'on', or you would have said so, right?

How many miles on the current spark plugs?
Every 60k is a good idea.

Definitely a tranny fluid change if it's been 50k+ miles, and that *might* cure this, but I doubt it.
A FF change is always required about every 30k miles, but again that prolly isn't the solution here.

Your symptom sounds more like a Torque Converter Clutch that is hanging up.
A faulty TCC solenoid is the usual cause.
It may or may not send a trouble code to the computer, initiating a CEL.

There's not much you can do about TCC problems, since it's totally within the tranny and can't be serviced without removing the tranny.

Hope this helps,
-Rick

[daman]

I would do a COMPLETE tune up,,then go from there..

sounds like a miss from this side of the keyboard...

[murr2424]

the car has 90k miles on it. there are no indicator lights illuminated. the spark plugs and housing are new (have about 1,000 miles on them). should i expect a transmission failure in my near future or will it carry on like this w/o need for concern.

[murr2424]

the car got a complete tune up when i did a rebuild of the upper half of the engine in may....

[rixGAphx]

A '96 4-cyl with an auto *prolly* has a 4T40E transmission.
4=4 speeds, T=transverse, E=Electronic.
40 = For vehicles weighing less than 4000 lbs.
This is a slightly weaker tranny than a 45 or the musch stroner 60 in many (most?) V6 GA's.

Anyhow, 90k is generally middle-aged for the stronger trannies; IMO yours should have at least 35k left depending on how rough you drive.
So failure isn't imminent, as long as there aren't any other symptoms AND you do regular fluid changes (every 45k or so with 'moderate' driving style).

But that TCC is gonna fail sooner or later, irrespective of the rest of the tranny.
When it does, it will either fail in the 'engaged' position which is a complete PITA, or it will fail un-engaged.
Modern TC's like yours are made for excellent torque multiplication and lousy gas milage when the TC clutch isn't engage, so even though the car works you will not like your crappy milage.

So either way, somebody must go into the gearbox to fix the Thing.

Assumning that is the problem.

IIWY, I would go to a large, reputable tranny shop and get their opinion, and an estimate.

But first, I would unplug/replug the tranny electrical connector (large, multiwire fitting right on top of the tranny 'bellhousing', kinda beneath the master cylinder.
Doing so will often clean corrosion from the connector pins and sockets, restoring full current flow and proper operation.

Hope this helps,
-Rick

[jessman1128]

Originally posted by rixGAphx
A '96 4-cyl with an auto *prolly* has a 4T40E transmission.
4=4 speeds, T=transverse, E=Electronic.
40 = For vehicles weighing less than 4000 lbs.
This is a slightly weaker tranny than a 45 or the musch stroner 60 in many (most?) V6 GA's.

Nope, we have the 4T60-E too. The Cavaliers and Sunfires got stuck with the 4T40-E's. (Or at least that's what I'm reading...I have no first-hand knowledge of any of this, so I could be wrong.)

On a side-note: I wish mine only had 90k miles! huge difference between 90k and 210k. :(

[murr2424]

a little different symptom this weekend....i was driving at 55 when all the sudden the trottle stuck and the car started accelerating. i stopped the car and turned the engine off and put it in park. i tried to restart the engine and it rev'd up to 3 & 4 revolutions with no sign of stopping or leveling off, so i turned the engine off immediately. next time, i started it, i gave it some gas and it went back to normal idle speeds. It fluttered a little after that, but then went back to normal operation. this doesn't sound like a tranny problem, so maybe i have a different or addition problem. any ideas?

[rixGAphx]

Have you ecently done any work on the car??

Like install a CAI, or otherwise messed with the air intake piping?

I'm thinking an intermittent vacuum leak would cause the rpm 'spike', as well cause as the old 'sputters on acceleration' symptom.
Vac problems usually don't cause a 'code', and they are disquised once the engine rises in rpm.

A LARGE vac leak, say 1/2" or greater (like a fitting on the air intake after the throttle plate) will allow a LOT of air to enter the intake manifold; the O2 sensor will detect the lean-ness, and the PCM will add fuel.
So the engine will just climb in power/rpm, as though you had floored the gas pedal (or just like the cruise control got a mind of its own).

I would look all over that engine for possible vac leaks.

Hope this helps,
-Rick