Transmission Problem or Engine Problem?
- Thread starter flyboy1100
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chengny
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just weird that it is part throttle, only in OD, and only once there is a load on the engine. been trying to research this, but it is tough for sure. so many possibilities.
This has been kind of bugging me and I am now not so sure about it being strictly a transmission issue. I mean, it still certainly could be (just transmission related), but I can now also see how a poorly performing engine might manifest itself in the situation you describe.
Because, when you think about it - if your engine is operating below peak performance, that fact would become most apparent in exactly this scenario.
The sudden spike in engine load that occurs when a clutch is engaged too quickly (on a truck with a manual transmission), is essentially the same as what happens when the torque converter locks up - you create a inflexible coupling between the motor and the drivetrain.
We all know what happens when a kid is first learning how to drive a "stick" and he pops the clutch for the first time his life. Unless he's some kind of a natural, the car is going to do the bunny hop. Once that jouncing starts, no amount of accelerator application is going to stop the hopping. He has to drop the engine load by dis-engaging the clutch. When things calm down, He tries it again. But this time he knows that he has to bring the revs up before applying a load (and also apply the load slowly).
When the kid revs the engine, that is equivalent to your motor being in satisfactory operating condition. I don't know enough about torque converter clutches to say how they actually operate. Are they supposed to engage the hard-coupled load gradually or are they designed to slam it on?
But if your motor is struggling (but not so bad that it is apparent while the torque converter is in slip mode) and you hit the accelerator after the TCC lock up - could that be the cause of the heavy vibration you are experiencing?
IDK - and I feel for you because it is difficult to diagnose. I mean, it's not as if you can grab a new motor (or transmission) off the shelf, change it out like a set of spark plugs and then observe whether operation improves. You basically have to do everything you can to ensure proper engine performance and then if things don't get better - you are probably looking at a new transmission.
After having said all that; I just became aware of this statement a few minutes ago:
(it was dark red and burnt smelling before i changed it).
Understand, smelly/dark ATF does not cause transmission problems. It's the other way around - transmission problems are what cause the ATF to become dark and smelly. IOW - by the time your ATF is like that - it is probably too late.
This has been kind of bugging me and I am now not so sure about it being strictly a transmission issue. I mean, it still certainly could be (just transmission related), but I can now also see how a poorly performing engine might manifest itself in the situation you describe.
Because, when you think about it - if your engine is operating below peak performance, that fact would become most apparent in exactly this scenario.
The sudden spike in engine load that occurs when a clutch is engaged too quickly (on a truck with a manual transmission), is essentially the same as what happens when the torque converter locks up - you create a inflexible coupling between the motor and the drivetrain.
We all know what happens when a kid is first learning how to drive a "stick" and he pops the clutch for the first time his life. Unless he's some kind of a natural, the car is going to do the bunny hop. Once that jouncing starts, no amount of accelerator application is going to stop the hopping. He has to drop the engine load by dis-engaging the clutch. When things calm down, He tries it again. But this time he knows that he has to bring the revs up before applying a load (and also apply the load slowly).
When the kid revs the engine, that is equivalent to your motor being in satisfactory operating condition. I don't know enough about torque converter clutches to say how they actually operate. Are they supposed to engage the hard-coupled load gradually or are they designed to slam it on?
But if your motor is struggling (but not so bad that it is apparent while the torque converter is in slip mode) and you hit the accelerator after the TCC lock up - could that be the cause of the heavy vibration you are experiencing?
IDK - and I feel for you because it is difficult to diagnose. I mean, it's not as if you can grab a new motor (or transmission) off the shelf, change it out like a set of spark plugs and then observe whether operation improves. You basically have to do everything you can to ensure proper engine performance and then if things don't get better - you are probably looking at a new transmission.
After having said all that; I just became aware of this statement a few minutes ago:
(it was dark red and burnt smelling before i changed it).
Understand, smelly/dark ATF does not cause transmission problems. It's the other way around - transmission problems are what cause the ATF to become dark and smelly. IOW - by the time your ATF is like that - it is probably too late.
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flyboy1100
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On my list today is transmission fluid/filter, plugs, wires, cap, rotor. Hopefully i get it all done otherwise i will be finishing it next week
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flyboy1100
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It would be nice to have a spare vehicle again...
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MadOgre
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Am I supposed to take that question seriously?
My point is that the engine is free to rev as it would be unlocked from the torque converter thus not loading the engine as it would be if the TC was locked.
350runner
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Take it how you want...
How you wrote your response sounded like you knew not what you spoke of. Try not mad all the time huh
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How you wrote your response sounded like you knew not what you spoke of. Try not mad all the time huh
Sent from the dust in front of you!
flyboy1100
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Truck was driven for a long time without tcc lockup, maybe why fluid smells slightly burnt.
Doesn't
Anyway, if this stuff today doesnt fix it, i plan to bring it to that tranny shop Monday
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Doesn't
Anyway, if this stuff today doesnt fix it, i plan to bring it to that tranny shop Monday
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MadOgre
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My response has nothing even remotely close to do with what you are posting. If you actually thought before posting it would probably benefit you a great deal.
350runner
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Yea I think alright... Try and post more like you do I'll record and send it to America's most funny videos and win. Haaaa
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flyboy1100
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OK, 2 issues for sure!
Cylinder #1
Wire still attached to cap, forgot to see which cylinder.. will post back
Need to figure out better wire routing, thought they were all safe from heat, guess not..
Did change filter and fluid as well, a little brownish in color, some sludge on magnet. So might be dealing with 2 issues.
Final question, how do i know if cap is ok? Rotor looked like possibly arcing and carbon buildup, cap looks pretty good, just some scratch marks on the contacts
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Cylinder #1
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Wire still attached to cap, forgot to see which cylinder.. will post back
You must be registered for see images
Need to figure out better wire routing, thought they were all safe from heat, guess not..
Did change filter and fluid as well, a little brownish in color, some sludge on magnet. So might be dealing with 2 issues.
Final question, how do i know if cap is ok? Rotor looked like possibly arcing and carbon buildup, cap looks pretty good, just some scratch marks on the contacts
Sent from my SCH-I605 using Tapatalk
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