Lock up issues, need help badly
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From: Hoover, AL
Lock up issues, need help badly first off, when driving past 40mph hptuners says that is commanding the converter to lock up. cruising around though the car drives like it is not locking at all, when the pcm commands lock up i think it dropped like 50rpms, sometimes it does nothing. when i let off the gas it decelerates like it is locked up. coasting down a steep hill, same thing, i tap the brake pedal and the rpms go up then come back down when i let off the pedal. i want to know what all causes this situation. we tried just about every tuning strategy and then returned it to its original tune that it was locking up on and now it doesnt lock. so what all mechanically and tuning, even though im pretty sure the shop exhausted all tuning possibilities, could the problem be? we had the car in drive stopped in a parking lot and commanded it to lock which should stall the motor but nothing happened. please help me with this my car has been acting like this for like 3 weeks and im getting tired of the shop waiting for outside opinions to roll in.
If the command is being made and there are no codes it is probably a converter issue
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From: Hoover, AL
well sometimes it throws a P1870 trans component slipping but it doesnt turn the MIL on when it does. the guy at yank doesnt think it is a converter issue, i'm not sayin your wrong cause i have no clue what the problem is. but he also said there might be blockage in the lines not allowing enough pressure to lock the converter. if the TCC solenoid screen was to be blocked with debree would that cause a "weak" lock up? also it was working just fine before i brought it in for the tune. i have a shift kit and he messed with the shift pressures is it possible that he screwed somethin up if the pressure was raised?
try another tune and drop the pan and take a look around
it is uncommon for the clutch to just go out
check a few things and call us back with findings as slipping from any cause can hurt the clutch lining.
it is uncommon for the clutch to just go out
check a few things and call us back with findings as slipping from any cause can hurt the clutch lining.
Well the screen in the PWM solenoid could cause poor lockup but if it was working fine before the tune I would have to agree with yank back to the tuning board. But also you may want to avoid driving much with it like that because as Im sure Yank will tell you also where you may not have a converter clutch problem now if something is causing it to slip you will soon enough .
You can actually check the screen in the PWM soleniod when you drop the pan simply by removing the solenoid ,
You can actually check the screen in the PWM soleniod when you drop the pan simply by removing the solenoid ,
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From: Hoover, AL
dont know if anyone read this yet but lack of a response tells me if you have you all are just as confused as i am. this is what i dont understand about it not locking up after we set it back to what it was when it was locking up?
I have given you what information I can . returning to stock tune if it locked up before should have made it lock up again unless theres some mechanical issue or other issue as listed above in my previous post , Unfortunatley I am not that familiar with the tuning end of this when you say changing tuning to stock do you mean the tuner just set the seting back to stock or do you mean a backed up program that is the stock program ?
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From: Hoover, AL
we pulled the original tune and saved it, after we had all the trouble tryin to get it to lock up i suggested putting the original tune back on it to see what would happen and nothing. thanks a lot by the way i really do appreciate the help, i dont mean to sound rude but after almost a month of this i am really getting irritated. it cost a lot of money for me to get a rock solid build done on this tranny and i'm gonna be pissed if it was ruined by a tuning mistake.
Crazy but here is one of my experiences. I tune B1ers car...00 ta with 60e. His did the same thing....l/u was fine......i added some fuel for WOT and then it wouldnt lock or it did once and thats it. Loaded back the original tune...no l/u...chased this all day and it wouldn't l/u. Next day when he left to come home from work...everything was FINE and no more l/u issues. We theorized that maybe the pcm has some sort of wierd l/u strategy that required a certain number of cold/hot driving cycles to reset or allow l/u. I ran into this same type thing when I first put in my 80e....it would l/u once and then no more until i cut the car off and restarted the car and then one l/u and no more. Next day, it worked like normal. Now under both circumstances, it would l/u manually with hptuners. On the other hand, during that same time, i had the converter manually l/u...didnt release it coming to a red light and it felt like a manual tranny...i almost hit the car in front of me because the converter couldnt slip with the l/u clutch engaged. Hope this helps some.
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From: Hoover, AL
that sounds like whats goin on except i have been on the stock tune for almost a week now and it wont lock up. when i get i free day i guess im gonna start pokin around in there if this other guy thats lookin at the tune for us doesnt have a answer for me.
I was having a lock, unlock problem, Not quite like yours, Did you raise the mis-fire codes to max? That fixed my problem, Don't tell me how because I didn't do it myself. From my experience is if you can't lock & unlock the converter with the tuner you could have a trans or verter problem..I was told to change the TCC selenoid 1st, Oh yeah & I have the Yank SS4000 like you
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Braking will ALWAYS unlock a locked converter. You can't lockup a converter for a car that is not moving - not that I know of anyway - car must be moving. I would revisit your tune or get it looked at by someone else if you are getting nowhere. Also check that the converter IS locking by a scan tool. You should monitor the slip RPM and the converter lock-up PID. If its slipping when a full lock is commanded (not a patial apply, coast or release, but "-Locked-") then you either have too little apply pressure, locking it up too low or the converter clutch is shagged. Exhaust your tuning causes first - much cheaper than dropping the tranny.
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From: Hoover, AL
thats the thing though, im pretty sure we have exhausted all the tuning possibilities, the guy is checking with other really good tuners to make sure that we have but oh well. its just my luck that its mechanical
how bout sending your file to me ( a bad tuner) and let me have a look at it...not that it will help but maybe i will see something 
cablebandit@comcast.net
cablebandit@comcast.net