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I need help. Turbo and trans.

Nessmuk

Nessmuk

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East Amazonian polar region
Having issues with my turbo and transmission.
Turbo: my boost reads 5 psi. I went to turn up the boost and I can't shorten the boost control rod any shorter and still get it on despite pulling on the vacuum chamber to try to get the bolts in the holes again.
Is that normal?
Transmission: It won't shift up under throttle. I have a U.S. Shift, quick shift 4. It isn't showing any codes. It will shift up so long as I'm off the throttle and up to speed. I've reset the throttle position sensor and that was no help. It has the full pressure modification in it as well.
 
Fill out your signature so we know what we are working on. I am a db2 guy, so i point at tps as starting point if you have one. Check voltage at idle and wot.
 
I have a 6.5, DB2, 4l80e, us shift computer for the transmission. Hx40w2 turbo.
I've been over the TPS twice and even relocated it once and redid the linkage. It seems ok in the computer, as it shows values from it.
 
Nessmuk said:
Having issues with my turbo and transmission.
Turbo: my boost reads 5 psi. I went to turn up the boost and I can't shorten the boost control rod any shorter and still get it on despite pulling on the vacuum chamber to try to get the bolts in the holes again.
Is that normal?
Transmission: It won't shift up under throttle. I have a U.S. Shift, quick shift 4. It isn't showing any codes. It will shift up so long as I'm off the throttle and up to speed. I've reset the throttle position sensor and that was no help. It has the full pressure modification in it as well.
Click to expand...

Check for exhaust leaks pre turbo, and leaks on boots connecting turbo to manifols (most likely this).
 
I found the flange clamps loose after the turbo outlet.
I have a antifreeze leak. It's boost related. I pressure tested the cooling system. It only holds 5 psi, I can't get it higher than that either. It also sprays antifreeze when under boost, which only achieves 5 psi. No antifreeze in the oil. No pressure builds in the cooling system at idle.
Any ideas where the leak is?
 
You said it sprays antifreeze under boost. Can you see it spraying or can you feel it spraying.
 
Wanting to help, but I am very confused on the descriptions.

My understanding is problems are:

1. Coolant system has a leak, and only holds 5psi, but you can not see where the coolant is going to.

2. You can not gain more than 5psi turbo boost.

Somehow you are seeing a connection between these two issues?

3. Transmission is not downshifting when under acceleration, nor upshifting when easing off the throttle to maintain speed.

Are these correct?
 
Nessmuk said:
I have a 6.5, DB2, 4l80e, us shift computer for the transmission. Hx40w2 turbo.
I've been over the TPS twice and even relocated it once and redid the linkage. It seems ok in the computer, as it shows values from it.
Click to expand...
So this is a Manual build? As in no computer except the one you got for the 4L80E?
PCS is better controller then the us shift. ;) I just had to jab ya with that one.
But yeah fill out your signature info to include all the diesel rigs or all rigs that you work on. It really helps the guys. Take mine for example. One look at my signature and they know I'm a lost cause. hahahaha
 
Nessmuk said:
Having issues with my turbo and transmission.
Turbo: my boost reads 5 psi. I went to turn up the boost and I can't shorten the boost control rod any shorter and still get it on despite pulling on the vacuum chamber to try to get the bolts in the holes again.
Is that normal?
Transmission: It won't shift up under throttle. I have a U.S. Shift, quick shift 4. It isn't showing any codes. It will shift up so long as I'm off the throttle and up to speed. I've reset the throttle position sensor and that was no help. It has the full pressure modification in it as well.
Click to expand...
I also have a Quick Shift 4. I don't remember where it is in the program, but there's a setting somewhere that delays upshift after heavy/full throttle. Maybe that needs to be adjusted?

Has it always had this problem? Have you just tried the stock 4L80 Diesel program from US Shift?
 
n8in8or said:
I also have a Quick Shift 4. I don't remember where it is in the program, but there's a setting somewhere that delays upshift after heavy/full throttle. Maybe that needs to be adjusted?

Has it always had this problem? Have you just tried the stock 4L80 Diesel program from US Shift?
Click to expand...
Also I was thinking about the upper TPS voltage limit in the controller - what if the limit was set lower than what your TPS actually does at full throttle, maybe that could be the problem?
 
Nessmuk said:
I was on the phone for 35 minutes yesterday working with them. They are sending me another with a different program as I do not have a computer to do it myself.
Click to expand...
Very good. My experience with them on the phone while figuring out my tach signal was good. I hope you had the same experience.
 
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