bad shift noids ?
Thread Starter
Teching In
Joined: Oct 2002
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From: houston
bad shift noids ? 99 z28 yank 4000ss stall , tranny built by local shop , trans had this prb b4 build though . from a dead stop , i take off car gets to 5 mph and drops second gear , regardless of tp , unless its wot , also has some down shift issues , sometime it will sometimes it wont ...... also shift firmness varies ... some times soft simetimes drops the next gear (hard shift ) . converter lock up issues aswell . EG wot on freeway converter hesitates or wont lock up , some cases if i let out of it and get back in it , it will lock up .also misshifts at wot 2-3 shift wont drop 3rd until i let out of it and then it shifts , also in that same scenario sometimes it will hang on the shift the car will wind down for a split second then shift . all this stuff is totally random sometimes it does sometimes it dont . im pretty much lost 
..lol So is it bad tranny tunning in pcm or or bad noids ? ANY help would be greatly appreciated.
..lol So is it bad tranny tunning in pcm or or bad noids ? ANY help would be greatly appreciated. 
FormerVendor
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
99 z28 yank 4000ss stall , tranny built by local shop , trans had this prb b4 build though . from a dead stop , i take off car gets to 5 mph and drops second gear , regardless of tp , unless its wot , also has some down shift issues , sometime it will sometimes it wont ...... also shift firmness varies ... some times soft simetimes drops the next gear (hard shift ) . converter lock up issues aswell . EG wot on freeway converter hesitates or wont lock up , some cases if i let out of it and get back in it , it will lock up .also misshifts at wot 2-3 shift wont drop 3rd until i let out of it and then it shifts , also in that same scenario sometimes it will hang on the shift the car will wind down for a split second then shift . all this stuff is totally random sometimes it does sometimes it dont . im pretty much lost ..lol So is it bad tranny tunning in pcm or or bad noids ? ANY help would be greatly appreciated.
..lol So is it bad tranny tunning in pcm or or bad noids ? ANY help would be greatly appreciated.How old is your unit? How long has the converter been in it?
If it is short shifting the 1st thing I always ask is what gear is in it? If that has not changed the next thing to do is have your tune checked... what mods does your car have?
g
Thread Starter
Teching In
Joined: Oct 2002
Posts: 28
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From: houston
Sorry about that
, Heads , cam car , mosier rear-end 3.73's .car still acted the same b4 rear end change . Im faily sure the prob is isolated in trans but as i had stated b4 not sure if uts the noids , or bad tuning . What i meant about drops is it goes to 2nd gear quickly,light turns green you remove foot from brake and lightly press gas pedal you start to roll and boom it shifts to 2nd . Unit is a almost 2 years old but very little mileage on it car is a weekend warrior really . maybe 10k on tranny .
, Heads , cam car , mosier rear-end 3.73's .car still acted the same b4 rear end change . Im faily sure the prob is isolated in trans but as i had stated b4 not sure if uts the noids , or bad tuning . What i meant about drops is it goes to 2nd gear quickly,light turns green you remove foot from brake and lightly press gas pedal you start to roll and boom it shifts to 2nd . Unit is a almost 2 years old but very little mileage on it car is a weekend warrior really . maybe 10k on tranny . 
It really sounds like a tuning issue to me. If your car had not been tuned for the rear end ratio change that is a huge problem. Also you say that it did before the trans was done. Not sure how far you are from the Dallas FW area, but you should set up a time to swing by and see the boys at ACE transmissions. Good guy's over there and they would never steer you wrong.
FormerVendor
Joined: Oct 2006
Posts: 3,123
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From: D-F/W
If the solenoid(s) were inoperative then the transmission would not upshift. They do not arbitrarily upshift or downshift... they either operate or do not, or they operate intermittantly. Another way they can fail is to have excessive debris build up in the exhaust ports. What you have described is a condition that is being commanded by the PCM.
That being said, I highly recommend you have the tune looked at. Meaning, if it is short shifting it is being commanded to do so. If the local shop had done their job properly they would have replaced all of the solenoids at the time of the rebuild, I am sure they had good cause for not doing so... but that is a shortcut we and other performance shops do not take. If you suspect the solenoids are faulty... replace tehm all.
Good Luck.
g
That being said, I highly recommend you have the tune looked at. Meaning, if it is short shifting it is being commanded to do so. If the local shop had done their job properly they would have replaced all of the solenoids at the time of the rebuild, I am sure they had good cause for not doing so... but that is a shortcut we and other performance shops do not take. If you suspect the solenoids are faulty... replace tehm all.
Good Luck.
g
