looking for input again.

gjp

gjp

another post whore
My truck feels like its not downshifting or something is slipping at WOT.
Under part throttle it feels fine.
WOT the truck revs up but does not take off fast. It is faster at 50% trottle then 100%.
I have checked the wireing on the 80e and it all looks good.
My truck did this before and I assumed the trans was shot. The trans had black stuff in the pan so I assumed the clutches were gone. This trans is new.
Is it possible a Transfer case going bad would cause this? perhaps if the clutch is slipping only at wot? I dont know. Any ideas. Thanks.
 
Last edited:
George Blake

George Blake

DONATING MEMBER
Re: looking for input again.

TC normally means "torque converter". Xfer case or transfer case is probably what your talking about. Get a datamaster on that thing and make sure your engine is happy FIRST. It's usually a given that guys do that after a rebuild to make sure everything is back together correctly.

You also need to hook up a pressure gauge and datalog with the TCI and see what that controller is being fed.
Until you look at what your sensors are sending the ECM and the TCU, you won't have a starting point.

There's some information on diagnosing the transfer case if you run a search. Our transfer cases don't have any clutches in them in the traditional sense. They are have a viscous coupler. An internet search on that will probably bring up the German company that made the one in the Borg Warner setup we have.
gjp said:
My truck feels like its not downshifting or something is slipping at WOT.
Under part throttle it feels fine.
WOT the truck revs up but does not take off fast. It is faster at 50% trottle then 100%.
I have checked the wireing on the 80e and it all looks good.
My truck did this before and I assumed the trans was shot. The trans had black stuff in the pan so I assumed the clutches were gone. This trans is new.
Is it possible a TC going bad would cause this? perhaps if the clutch is slipping only at wot? I dont know. Any ideas. Thanks.
Click to expand...
 
gjp

gjp

another post whore
Re: looking for input again.

sorry ment Transer case. I have about 10 dm runs since I got my truck running. Running 15 psi right now. Knock is hardly nothing. All sensors show good. At part throttle engine is strong. wot the engine will rev to 4500-4800rpm but does not pull as hard if I would just to give it part throttle.
 
George Blake

George Blake

DONATING MEMBER
Re: looking for input again.

That sounds like timing. If it did it before AND you've changed everything else, you may still have a timing issue. There are guys a LOT better than me on the engine end. You also need to get the voltage figured out. There is a default that the truck goes to when your voltage acts up and drops out or goes high. That was in the P4 document.

You still need to run a datalog on the TCU so you can see what it's getting. You also need to put a pressure gauge on it.

It sticks out like a sore thumb that it did this before and you have a completely different drivetrain and it's still doing it.
gjp said:
sorry ment Transer case. I have about 10 dm runs since I got my truck running. Running 15 psi right now. Knock is hardly nothing. All sensors show good. At part throttle engine is strong. wot the engine will rev to 4500-4800rpm but does not pull as hard if I would just to give it part throttle.
Click to expand...
 
gjp

gjp

another post whore
Re: looking for input again.

voltage issue is fixed. where do I find a pressure guage and where does it hook up.
 
gjp

gjp

another post whore
Re: looking for input again.

timming??? dont get that one?
This thing is taking up to much time and money. All this work for a 12 sec truck.....
Just thinking I will drive it hard till it blows and call it done. Part it out or something. I am tired of this shit. I can build a 11 sec 72 elcamino but I cant make this ****ing stupid little truck run right.
 
TYTILIDIE

TYTILIDIE

METH HEAD
Re: looking for input again.

What are you using for a chip? If its custom done, you could have a flat spot somewhere seeming like a slip. Thats probably what George is saying. Ive experienced this and its real easy tjo fix if you tune yourself.
 
gjp

gjp

another post whore
Re: looking for input again.

phil long 50# chip. I have 2 of them so I will try them both. When I get on it its not like its not as fast. It does not pick up any speed at all. I will try to post some DM runs tomorow.
 
George Blake

George Blake

DONATING MEMBER
Re: looking for input again.

TYTILIDIE said:
Does it over rev?
Click to expand...
He described it as the truck is still pulling but not nearly as hard as it does at part throttle. He also said it was doing the exact same thing before the buildup. That really stuck out. He needs to run a pressure test and datalog with the TCU.
 
TYTILIDIE

TYTILIDIE

METH HEAD
Re: looking for input again.

If its kind if just "going falt" so to speak I would definately say its a tune issue. As long as its not over revving you dont have a trans problem. I have experienced first hand what you are talking about if Im understanding the description right and it is frustrating but a little work and Im sure you can get it right. Do you have a DM file by chance? Are you watching your timing as youre doing a run? If so, whats it doing? I ahd this happen on my Vette years ago and at the time cold nt figure it out and never did but I got a lot smarter with the TY and had this problem a few times and as it had turned out, my timing had a strange blip in the table and all I had to do was change it. Could also be a fuel issue, I dont know what you have to diagnose fuel but Ild look into that as well.
 
gjp

gjp

another post whore
Re: looking for input again.

answer first question. No It did not over rev. The first trans did. It would hit 5200rpm. This time it was not.
Today I changed chips and turned the alky down to 2. I could have been oversprayng??????
Did a 10lb boost launch and took it up to 60mph. First off it spooled to 10lbs fast. took about 2 seconds up to 3000rpm and I was at 10.5lbs. Felt good. Still shifts off. Thinking the low voltage might have messed with the program. Looking for someone with a serial laptop I can borrow. Mine does not work for the tcu. Sounds like its the chip or the alky spraying to much. With the alky turned off with strait 91 octane I am seeing 1.6* of Knock at 17psi. I will dial in the alky to see whats up.
Still would like to have george test the computer and reprogram if possible. Again george I will pay for your time. At this point it would be cheaper then getting a new laptop.
 
George Blake

George Blake

DONATING MEMBER
Re: looking for input again.

I would have no problem looking at it, but if you had a datalog of the run accompanied with things you would like changed, I could kill two birds with one stone. I could even take your program, mod it and email a config file and you could program it in right there. Wouldn't cost you nothing. I'm just trying to take care of you so you don't spend any money you don't have to.

gjp said:
answer first question. No It did not over rev. The first trans did. It would hit 5200rpm. This time it was not.
Today I changed chips and turned the alky down to 2. I could have been oversprayng??????
Did a 10lb boost launch and took it up to 60mph. First off it spooled to 10lbs fast. took about 2 seconds up to 3000rpm and I was at 10.5lbs. Felt good. Still shifts off. Thinking the low voltage might have messed with the program. Looking for someone with a serial laptop I can borrow. Mine does not work for the tcu. Sounds like its the chip or the alky spraying to much. With the alky turned off with strait 91 octane I am seeing 1.6* of Knock at 17psi. I will dial in the alky to see whats up.
Still would like to have george test the computer and reprogram if possible. Again george I will pay for your time. At this point it would be cheaper then getting a new laptop.
Click to expand...
 
George Blake

George Blake

DONATING MEMBER
Re: looking for input again.

Alky can do bad things if you are not doing it right. I don't know how much they want shared but at homecoming, there was a team with issues with alky and they said the truck would just flat fall on it's face with too much alky. It seems like they thought it was a tranny issue as well initially.
 
gjp

gjp

another post whore
Re: looking for input again.

never had a BS3. Looks like a lot of work to wire one of those in. Someday I plan on having a build like Dean. Just a stock ecu and 50# phill chip. I will try the other chip with no alky.
I had the alky set to 3 and it still was overspraying??? I have to tweak it.
I will look for a cheap laptop. I will give it a week then if I cant find nothing I might send it back.Thanks George.
 
George Blake

George Blake

DONATING MEMBER
Re: looking for input again.

There's too many guys on here running alky. Go to the engine/tuning forums and see if you can find anything specific on alky. There's no plug and play chip yet. At WOT, the alky needs to be adjusted because it really throws off the Wide Band O2 setups. The alky guys would be able to tell you what A/F ratio you'll have to shoot for.
 
JSM

JSM

Active member
Re: looking for input again.

~11:1 with alky on, but it all depends on how much your spraying also.

Jeremy's sy where we spray a ton of meth, it likes 10.8:1 @ 26psi of boost.

As mentioned though, and one of the things I keep trying to tell people is a custom tune for any truck is the only way you are going to get out everything.

Either go code59 or hire one of the tuners on here to help you.
 
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