Hard 1-2 Shift, Looking for Some Expert Help!
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Teching In
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Hard 1-2 Shift, Looking for Some Expert Help! I have a 94 Trans Am with the A4 and my trans has been acting up recently. The transmission will hold 1st gear until about 4k sometimes higher when accelerating slowly. But I can always get it to shift into 2nd by letting off the gas slightly. The 1-2 shift seems fine under harsh acceleration but every once in a while it will bounce off the rev limiter in 3rd.
Some helpful vehicle specs and background:
-Purchased car totalled from a friend, the trans had 500 miles on a "complete" rebuild (according to recipt) I assume it is a completely stock setup.
-Got a rolling chassis and swapped everything over.
-Put about 7k on it since the restore so trans has less than 8k on it.
-About 500 miles ago I replaced the Trans mount as it completely failed. So I am not sure if these two could be related?!?
I tried using the search feature but didnt/couldnt find anything that seemed to relate to my situation. Some were close but were never really completely answered. Thank you in advance for any ideas help and guidiance....
Some helpful vehicle specs and background:
-Purchased car totalled from a friend, the trans had 500 miles on a "complete" rebuild (according to recipt) I assume it is a completely stock setup.
-Got a rolling chassis and swapped everything over.
-Put about 7k on it since the restore so trans has less than 8k on it.
-About 500 miles ago I replaced the Trans mount as it completely failed. So I am not sure if these two could be related?!?
I tried using the search feature but didnt/couldnt find anything that seemed to relate to my situation. Some were close but were never really completely answered. Thank you in advance for any ideas help and guidiance....
You need to scan the car for codes and see what happening there first the 60e likes in your car is completely controlled by the PCM it only does what its told.
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Since I have a 94 I will need the OBD-I scanner correct? I know that Autozone around here doesnt have them or loan them. Anyone know of a place to rent one or buy one cheap?
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I had the car scanned today and it threw a couple different codes:
16 Low Resolution Pulse Failure
32 EGR Problem
71 A/C Evaporator Temp Sens
18 Crank SIgnal Open or No signal
22 TPS to low
58 Trans Temp High
From what I have read 16 and 18 are due to a bad opti signal. My Opti did recently take a dump so I replaced it with a MSD unit. I am assuming these are old codes. I havent charged the AC yet so that takes car of code 71.
That leaves code 32, 22, and 58. I just put a new TPS sensor in it and that changed nothing. I am going to do a trans flush and see if that helps anything. (heat related) But that still leaves code 32 which I will have to maybe replace the egr.
Anyother ideas?
16 Low Resolution Pulse Failure
32 EGR Problem
71 A/C Evaporator Temp Sens
18 Crank SIgnal Open or No signal
22 TPS to low
58 Trans Temp High
From what I have read 16 and 18 are due to a bad opti signal. My Opti did recently take a dump so I replaced it with a MSD unit. I am assuming these are old codes. I havent charged the AC yet so that takes car of code 71.
That leaves code 32, 22, and 58. I just put a new TPS sensor in it and that changed nothing. I am going to do a trans flush and see if that helps anything. (heat related) But that still leaves code 32 which I will have to maybe replace the egr.
Anyother ideas?
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Teching In
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I removed the pan and changed out the filter. The fluid had a small burnt smell but it wasnt really bad. There was no shavings in the pan at all, but the filter was definetly black. Filled it out with some fresh fluid but I still have the same result.
It will hold 1st gear until you slightly let of the gas then it will shift. (at both WOT and "easy" driving) It will hold it right up the rev limiter. Usually the 2-3 shift if fine but it has acted up on it a couple of times. The 3-4 will bounce off the rev limiter at WOT.
The car doesn't have a sector for gear 1, but I am assuming you can put it in gear one. If this is true, when I start out in "first" then hold the gas as i shift into second it still will not "shift" until I let off the gas.
Broken spring? or Bad servo?
It will hold 1st gear until you slightly let of the gas then it will shift. (at both WOT and "easy" driving) It will hold it right up the rev limiter. Usually the 2-3 shift if fine but it has acted up on it a couple of times. The 3-4 will bounce off the rev limiter at WOT.
The car doesn't have a sector for gear 1, but I am assuming you can put it in gear one. If this is true, when I start out in "first" then hold the gas as i shift into second it still will not "shift" until I let off the gas.
Broken spring? or Bad servo?
On The Tree
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From: Down Under
When you swapped your friends combo to your car did you retain the same diff ratio, stall convertor/ speed? It sounds like a calibration issue or possibly a wiring fault, either to a solenoid or in the loom outside the box. I recently had 2 intermittently faulty solenoids but when we did all the checks it was throwing codes for lots of other stuff. We got an open circuit relating to the shift solenoids when we checked with a multimeter.
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When you swapped your friends combo to your car did you retain the same diff ratio, stall convertor/ speed? It sounds like a calibration issue or possibly a wiring fault, either to a solenoid or in the loom outside the box. I recently had 2 intermittently faulty solenoids but when we did all the checks it was throwing codes for lots of other stuff. We got an open circuit relating to the shift solenoids when we checked with a multimeter.
Everything was swapped from one chassis to the other. The car I bought was simply a rolling chassis (basicly just a tub) that the guy was gonna make into a race car but never got around to do anything with it so it worked perfect for me to replaced the accident damaged parts on mine. Also everything worked excellent on it for the first 8k miles I put on it after I put it all back together.
It didnt start acting up until the tranny mount went out of it. And I mean by going up the mount ripped in two so the trans was no longer held down in the back. I didnt realize the problem until the trans came up and slapped the body.
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Your code 58, (high trans temp), could be causing this problem. If the computer is seeing this, it's possible your trans is shifting late due to this problem. Clear the codes, now that you've written them down. See if the trans shifts fine. If it does, watch and see if the light comes back on. At the same time the trans should act up. If you clear the code and the trans acts the same, take it to a shop and get a more thorough scan or diagnostic done. Electronic problems can be a bear. Especially after you've changed so much. Check all of your grounds, etc... I know sometimes people in our area go to Auto Zone and get scanned. They only record some codes. We have an ellaborate scanner. It catches everything. Customers ask why. I attribute it to a cheap scanner. The more expensive scanners have better diagnostic capabilities to catch all of the DTC's. Hopefully this helps.
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^^Thanks for the info.
My car is a 94 so it is pre obd-II (autozone scans OBD-II for free) but is is post doing the paper clip trick. Last Friday when I had it scanned it cost me a couple bucks. I did get some info, and then they did clear the codes. It seemed to operate the same after that.
On Sunday, the ses light came on right as I was taking off from a stop light, when the car was in first. Then at the same time that I left off the gas (to try and allow it to "shift" ) the ses light shut off. It hasnt come back on since. I ordered a data log cable today so hopefully later this week I will be able to scan for a couple codes and maybe even makes some logs so I can see if i find the problem.
My car is a 94 so it is pre obd-II (autozone scans OBD-II for free) but is is post doing the paper clip trick. Last Friday when I had it scanned it cost me a couple bucks. I did get some info, and then they did clear the codes. It seemed to operate the same after that.
On Sunday, the ses light came on right as I was taking off from a stop light, when the car was in first. Then at the same time that I left off the gas (to try and allow it to "shift" ) the ses light shut off. It hasnt come back on since. I ordered a data log cable today so hopefully later this week I will be able to scan for a couple codes and maybe even makes some logs so I can see if i find the problem.
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I got my data cable today so I could actually see what is going on. After rescanning my system there turned out to be no new codes. (just the a/c system one which I expected and the EGR fault which must have been the trigger of the light I saw). The EGR wouldnt effect my trans in some backwards way would it??
Anyone have a good suggestion for trans monitoring software? Using Datamaster I was able to kinda watch what its active gear is suppose to be at cetain speeds and with cetain slip rpm and rpm16. I can email anyone the file if they can read it better than I. The active gear moves from D1 to D2 even though the rpm gauge doesnt change and you cant feel any shift. Then once you let some pressure off the gas pedal the active gears goes from d2 quickly into d3 and then into d4. Anyone have any insight?
Anyone have a good suggestion for trans monitoring software? Using Datamaster I was able to kinda watch what its active gear is suppose to be at cetain speeds and with cetain slip rpm and rpm16. I can email anyone the file if they can read it better than I. The active gear moves from D1 to D2 even though the rpm gauge doesnt change and you cant feel any shift. Then once you let some pressure off the gas pedal the active gears goes from d2 quickly into d3 and then into d4. Anyone have any insight?
Are you sure your even making the 2-3 shift and are not actually allways skipping it, Heres and idea put the car in manual 2 does it ever shift from 1-2 or just stay in first ?
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Well I just took it out for a spin. Just leaving it in second gear I couldnt feel the 1-2 shift ever. But I could shift down to first so I know it is still there. I could start out in first though and then when I shifted to second it would still stay in first until I let a little pressure off the gas..
