jammey97 Posted March 6, 2003 Report Share Posted March 6, 2003 Hey all, Just got a '91 Lumina Z34 for dirt cheap. Noticed that the automatic transmission is always starting out in 2nd gear. Manually selecting first gear doesn't make any difference (aside from preventing upshift to third). All other gears shift and feel fine. Any ideas? Comments? Flames? Thanks in advance for any input. Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted March 6, 2003 Report Share Posted March 6, 2003 That is strange. So, your sayin, you can floor it from a dead stop and it wont shift till like 70mph? Will it event take off in second?? I thought it might just die, cuz the gear is only 1.6:1 for second. Anyway.....have you changed the fluid lately?? Always, do that first if you have a tranny prob. That will usually clear things up. But, if not, that sounds pretty fatal to me. Like a rebuild would be in order cuz the 1st gear clutch is shot or something Robby BTW: Welcome!! Quote Link to comment Share on other sites More sharing options...
jammey97 Posted March 6, 2003 Author Report Share Posted March 6, 2003 Fluid/filter change is the first thing on my todo list. Just thought I'd ask and see if anyone had encountered this before. Yea it does take off in second though there's not much power till it reaches 20mph or so. Stomping on the throttle doesn't downshift from 2nd at all. I'd imagine that is giving the torque converter one heck of a workout. I have noticed that when I shift into gear from Neutral, Reverse or Park, it does go into 1st gear for about half a second, then goes right into 2nd gear. Quote Link to comment Share on other sites More sharing options...
jammey97 Posted March 6, 2003 Author Report Share Posted March 6, 2003 OK fluid and filter changed, still no 1st gear =/ If it's electronically controlled, could there be a relay somewhere that's burned out? Or perhaps stuck on? Quote Link to comment Share on other sites More sharing options...
Redfox340 Posted March 6, 2003 Report Share Posted March 6, 2003 Well, it could be the Control Valve Assembly according to my service manual. Says the cause is by a stuck 1-2 shift valve; to CVA is located inside the tranny underneath the side pan cover... and won't get better with time. You might want to get it looked at; have pics from service manual if needed. page numbers: (reference) 4T60-E-35 = auto tranny dignostics 4T60-E-8 = CVA removal repair 4T60-E-53 = CVA repair / dissasembly - RedFox340 Quote Link to comment Share on other sites More sharing options...
jammey97 Posted March 7, 2003 Author Report Share Posted March 7, 2003 Damn... not what I wanted to hear. =/ If it is the CVA, is it safe to assume that would require removal of the tranny to fix? Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted March 7, 2003 Report Share Posted March 7, 2003 But if you have a 91 Z34, then you have the regular 4T60 right?? It is not electronically controlled, so, your 1st gear switch or solenoid maybe faulty. Heres an easy way to check. On the front of the trans, (like the face of it close to the actual front of the car), close to where the engine and trans meet, there is a 5 prong plug. This plug controls, TC lock up, 1st gear switch, 1st gear solenoid, 4th gear switch, 4th gear solenoid. Pull this connector. If you pull it and you get 1st gear back, then your 1st gear solenoid or switch is possibly to blame. Now, if you pull it, you WILL NOT have any torque converter lock up, just so you know. I would pull that connector and see what happens. If that doesnot do, what Redfox 34 said is probably it. If you do have the 4T60, then the computer WILL NOT throw codes for the tranny. If you have the E version it will Robby Quote Link to comment Share on other sites More sharing options...
jammey97 Posted March 7, 2003 Author Report Share Posted March 7, 2003 Well according to the HUGE lettering on the tranny pan, it's a 4T60-E Perhaps the pan isn't origional? I always assumed that all Lumina Z34's with auto had electronic transmissions. Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted March 7, 2003 Report Share Posted March 7, 2003 If the pan says that, then you have the 4T60-E. I wasnt sure when the E was used, obviously in 91 lol. Anyway, run your engine codes and see what comes up. That might give you a starting point. But, yeah Redfox 34 is on the probable problem. Yeah Im pretty sure you would need to drop it to fix that. I would just do a rebuid on it while I was at it. Oh.....they make a shift kit for the 4T60 and 4T60E, that can only be installed during a rebuild. If you do rebuild or have to take it apart, inquire about that. Robby Quote Link to comment Share on other sites More sharing options...
jammey97 Posted March 7, 2003 Author Report Share Posted March 7, 2003 Just did the SES light diagnostic, just keeps repeating code 12 so no errors. Guess I'll have to make more room in my garage for this project. Any ideas where I can get my hands on a shop manual for it? Right now all I've got is the Chilton book, which is rather sparse when it comes to transmissions. Btw, thanks for all the info/help Robby and Redfox. Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted March 7, 2003 Report Share Posted March 7, 2003 Advance Autoparts or Autozone had manuals on transmissions. I dont know if they have one on GM FWD trannies, but I think they would, they are very common. Check there for a manual. Glad we could help......if you need antything else let us know, were more than happy to help you out! Hope you get ir working soon, Robby Quote Link to comment Share on other sites More sharing options...
patgizz Posted March 7, 2003 Report Share Posted March 7, 2003 all dohc auto cars got the 4t60-E check ebay for the service manual, they go there CHEAP. get the factory one. also if you can, find the 91 dohc service manual supplement. my book says for 2nd gear start to check: control valve assembly for stuck 1-2 shift valve 2nd clutch housing and drum for hot spots from band slipping. going to guess its #1. if reverse works then we can rule out the "A" shift solenoid and the wiring to it. this solenoid controls the 1-2 shift valve. therefore i'd venture an educated guess that the valve itself is stuck. Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted March 7, 2003 Report Share Posted March 7, 2003 all dohc auto cars got the 4t60-E Thanks for the info! Robby Quote Link to comment Share on other sites More sharing options...
Redfox340 Posted March 7, 2003 Report Share Posted March 7, 2003 Damn... not what I wanted to hear. =/ If it is the CVA, is it safe to assume that would require removal of the tranny to fix? Looks like it, since the tranny side pan must be removed and you've got to go about one layer down to get to the CVA. Sorry to tell you bad news on your first thread, but hopefully you can nip this thing in the butt before it goes worse. Best of luck, and sorry... I hate telling newbies bad news on their W-Body. - RedFox340 Quote Link to comment Share on other sites More sharing options...
JS91Z34 Posted March 7, 2003 Report Share Posted March 7, 2003 I heard the 4T60-E trans was a bad one. What I dont get is why would chevrolet put supposedly a bad design trans behind one of most powerful V6's(3.4L DOHC motor). I drive a 91 Z34 with a 4T60-E with just over 164,000 miles on it. I have not had a problem yet. The motor has been replaced though. Quote Link to comment Share on other sites More sharing options...
jammey97 Posted March 7, 2003 Author Report Share Posted March 7, 2003 Sorry to tell you bad news on your first thread, but hopefully you can nip this thing in the butt before it goes worse. Best of luck, and sorry... I hate telling newbies bad news on their W-Body. Ah well, to be honest I can't say I'm all that surprised. And bad news is better than not knowing at all. Any ideas what kind of cost would be incured getting a local shop to fix this? Quote Link to comment Share on other sites More sharing options...
ismellrealbad Posted March 7, 2003 Report Share Posted March 7, 2003 mine's 4T60-E paired to 3100 w/67k mi. everything shifts smooth as hell even on hard cornering. the only complaint i have is a slow-ass reaction time to flooring. can take almost 2 seconds sometimes to downshift a gear. god knows when the fluid was changed if ever. it still has its nice pink color and is up to level. The spark plugs must have never been changed. i pulled one and theres almost no tip. with i get $12 to blow and some time ill change it. i showed it to my dad he said he doesnt even know how the car is running if all them were like that (i only pulled one). Quote Link to comment Share on other sites More sharing options...
Whiskey River Posted March 7, 2003 Report Share Posted March 7, 2003 Any ideas where I can get my hands on a shop manual for it? Right now all I've got is the Chilton book, which is rather sparse when it comes to transmissions. Here is a link to ebay for the 1991 shop manual. It only shows book one but that covers a complete transmission tear down. http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2406451757&category=6760 Quote Link to comment Share on other sites More sharing options...
Redfox340 Posted March 7, 2003 Report Share Posted March 7, 2003 Any ideas where I can get my hands on a shop manual for it? Right now all I've got is the Chilton book, which is rather sparse when it comes to transmissions. Helm Inc. <http://www.helminc.com> is got the best, IMO, since they've workede with and certified by GM and ASE. These books are used at the dealership and other high quality automotive repair shops... check the site, there run a little steep on the price, but it's worth it when you want to know where something is and what could be wrong! You're looking for the "shop manual"... best of luck! - RedFox340 Quote Link to comment Share on other sites More sharing options...
patgizz Posted March 7, 2003 Report Share Posted March 7, 2003 unless the shop can possibly get the side cover off with the trans in the car(i dont see how) you are basically going to get hit pretty hard because tranny removal isnt easy. Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted March 7, 2003 Report Share Posted March 7, 2003 The side pan can come off with the tranny in the car. Robby Quote Link to comment Share on other sites More sharing options...
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