Open/Closed loop transmission function
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Cross-Country
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Open/Closed loop transmission function
Hopefully one of you can point me the right direction. My freshly built 4r70w is having problems going into third and beyond while at the tuner. I have a kenne bell on the 5.0 in a 1994 F150 4x4. The transmission got a shift kit and the converter was brazed and tightened up a bit. I did drive the truck for a while without the supercharger, without issue. I have not ruled out the shift kit and converter as the mistake that led to my problems. I am wondering if anyone knows what/if the computer does things differently for open loop/closed loop operation when it comes to transmission function.
Also, what's a healthy O2 signal?
Thanks a bunch!
Also, what's a healthy O2 signal?
Thanks a bunch!
Last edited by Bignasty2; May 28, 2023 at 11:46 AM. Reason: truck year
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Cross-Country
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THANKS!!!
Cargo Master
Joined: Mar 2007
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Metal in the fluid is not a good idea but you have to understand that you have a truck that is almost 30 years old. Just because someone touches it, does not mean they screwed it up. Yes, it can happen, but things break and sometimes they break when you are working on it or minutes after you have. Just because you do an oil service does not mean the flat tire is the mechanics fault.
That said, if I had that transmission out, I would have gone through it. It's 30 years old. There has got to be some wear items that need to be changed out.
That said, if I had that transmission out, I would have gone through it. It's 30 years old. There has got to be some wear items that need to be changed out.
Hotshot
Joined: Jun 2015
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Here is part of post #1 with highlighted words for you reread….
Cargo Master
Joined: Mar 2007
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My mistake. I read the post right above about the converter.
Metal, glitter, whatever words are used, there should not be any in the fluid. Not certain why you thought that I was recommending that.
A good rebuilder would want to check things out. I would remove it out and see what went wrong.
Metal, glitter, whatever words are used, there should not be any in the fluid. Not certain why you thought that I was recommending that.
A good rebuilder would want to check things out. I would remove it out and see what went wrong.
Hotshot
Joined: Jun 2015
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Because you used the phase that you did. It definitely need to go back to the shop that rebuilt the transmission to find out where that metal is coming from.
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Frmr Ford Trans Engr
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No, it's not a bad idea. I can't tell from here if anyone did a bad job or not.
A tighter converter won't starve anything. A misinstalled shift kit can starve something, but once again, I can't tell if anything was done right or wrong.
A supercharger without the proper trans hardware and tuning will DESTROY a transmission. Getting the tuning right with the supercharger could very well be the cause of your failure.
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Here is some info you may find interesting.
I have been tuning my stock 351w and have been having some intermittent hard/soft shifts depending on throttle position and load.
I only tuned fuel, nothing else.
I have put the stock tune back in due to other issues, and trans now shifts more smoothly all the time.
what I believe is going on is as you tune the engine, fuel tables etc. you will also need to tune the transmission tables as well, torque, rpm, 1-2,2-3, etc etc to match the engine power output.
im still learning, and I might be wrong
I have been tuning my stock 351w and have been having some intermittent hard/soft shifts depending on throttle position and load.
I only tuned fuel, nothing else.
I have put the stock tune back in due to other issues, and trans now shifts more smoothly all the time.
what I believe is going on is as you tune the engine, fuel tables etc. you will also need to tune the transmission tables as well, torque, rpm, 1-2,2-3, etc etc to match the engine power output.
im still learning, and I might be wrong
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Cross-Country
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You guys are awesome. I believe my tuner could be in a little on the deep side. It's really hard where I'm at to find someone to touch OBD1, so I am grateful. Is there some sort of resource I could point him to even if it's a paid thing? He may not have enough vehicle specific experience to be confident with the transmission portion. I'm not making crazy power by any means. I am putting out a good amount more torque and probably net more HP. I'm running rich with little timing on a little v8. If there was a guy that knew exactly what my transmission wanted tune-wise, I would pay for it and pay my guy to put it on there.
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