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Discussion Starter #1
Finally got the 'Stang out today for a quick spin, making a total of about 20 miles this year!. One thing ive noticed, both today and on previous occasions, is when you put your foot down, it momentarily wont accellerate, but revs high, then picks up the power. It only seems to happen for 10 minutes at the start of a run, and then goes.

To try to explain it a bit better, if you hit the throttle, in any way, it revs high, then seems to 'kick-in' and jerk a bit heavily as the power kicks in. It;s a D code 289 / C4 auto.

It might be related, but this car hardly ever sees the road. Its done 1,500 miles since the transmission rebuild - which if you can believe is 12 years ago!.

Any help greatly appreciated,

Gary
 

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Are you saying that it hesitates more when cold than when warmed up (for 10 minutes at the start of a run)?

What happens if you powerbrake the car in gear?

Which range are you selecting on the green dot trans when starting out?

Does the trans go into gear immediately and firmly when shifting into reverse or drive range?

Sorry about all the questions...*G*..just trying to understand better..
 

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Sounds like slippage in the C4. Best case is it is low on fluid, or the bands may need adjustment. Worst case, tranny may be telling you its time for extensive rebuild. Drop the pan, and change the filter. Sometimes just the act of putting the 4 or so qts of fresh fluid in as part of the filter change, works wonders.
 

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Discussion Starter #4
After about 10 minutes the problems goes away completely.

Its only ever run in Drive ("D"), so i dont know about "1" and "2". Reverse seems fine, but then i dont reverse at the same speed. It takes a second or two when reversing to START reversing, (getting revs up) but never has the problem mentioned above.

Sorry if this sounds stupid, but i cant figure out what you mean by "powerbrake" or "which range are you selecting. Showing my lack of knowledge here, lol

Thanks,

Gary
 

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Powerbrake = put foot on brake, shift into forward gear and press on accelerator, holding car with brake, and raise rpm until tire spins or rpm stops rising...noting any noises or shudders or other unusual events.

Range = On early trans, the first detent past neutral starts the car off in 2nd gear, with an automatic upshift to 3rd. The second detent starts the car off in 1st, with auto upshifts to 2nd and 3rd. The furthest detent is a manual low or downshift selection, depending on road speed..

Sounds to me like trans is hesitating before going into gear and, when cold, you have to rev it up a bit before it'll go into gear...am I understanding correctly?
 

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Discussion Starter #6
<blockquote><font class="small">In reply to:</font><hr>

Sounds to me like trans is hesitating before going into gear and, when cold, you have to rev it up a bit before it'll go into gear...am I understanding correctly?

<hr></blockquote>

This only happens when, say, you stop at a light and then go again (still in early stage of a run) The car will go, move forward, and then it momentarily stops accellerating, the revs rise, and then it picks up power again. All the time with your foot at the same point on the throttle.

I've never 'powerbraked' before, so cant give feedback on that.

I'm trying to explain it the best i can, so im sorry if im not being clear. I'm a total transmission newbie.

Thanks,

Gary
 

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How does the fluid level look on the dipstick when checked warm, with the engine running, in Park or Neutral?

Sounds to me like the level might be low and the oil goes to the back of the pan during acceleration, uncovering the pickup briefly...then the car hesitates, the oil flows back forward, gets picked up and the trans then operates again..

Pure speculation, but plausible..*G*
 

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Discussion Starter #8
I'll try that during the week and post the results. Im a patient man, im not in a hurry to get it done! lol

Thanks,

Gary
 

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You need to get out more. 20 miles a year is destroying everything you have built. Good example is "do tires dry rot when not used?"...yes. "Do transmission seals dry rot when not used?"....yes, Even though you are saving on wear and tear in some areas, you need to excercise the Pony or it will get lazy, weak and brittle. You may have already done irreversable damage to the seals and anything thing else that can deteriate over time. Lack of use speeds up the deteriation process.

Exercise that Pony more often!
 
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