augi Posted October 11, 2009 Report Share Posted October 11, 2009 I have a 99 z34 that I just bought a couple of months ago and while driving it home that day, I came to the realization that it doesn't have overdrive . It shutters slightly going from 1-2 if I baby it, but under normal and hard acceleration, it's just fine. Thanks for any help. Quote Link to comment Share on other sites More sharing options...
carkhz316 Posted October 11, 2009 Report Share Posted October 11, 2009 Rebuild time, most likely in order. No overdrive or TCC lockup? (just making sure) Quote Link to comment Share on other sites More sharing options...
augi Posted October 11, 2009 Author Report Share Posted October 11, 2009 TCC lockup? The torque converter works fine if thats what you mean. Quote Link to comment Share on other sites More sharing options...
carkhz316 Posted October 11, 2009 Report Share Posted October 11, 2009 Yeah, what I mean is the Torque Converter Clutch locking up? It usually does in 3rd gear, but sometimes in overdrive (but obviously in this case, it probably wouldn't in OD) Quote Link to comment Share on other sites More sharing options...
augi Posted October 12, 2009 Author Report Share Posted October 12, 2009 al right... please bare with me as far as spelling and grammer as i am posting this with my cell phone. to give a bit more insight, the car is running down the interstate at 70 mph at 3000 rpm... ill put it into od and it revs up a bit like the tcc unlocks runs for a minute at 3500, then the tcc locks again and it goes back down to 3000 andthen when i let off the gas... it drops to 1000rpm. hit gas again and it revs all the way back to 3000 rpm and goes again. on D it just stays around the rpm its already running at. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 12, 2009 Report Share Posted October 12, 2009 it does sound like 4th gear is NOT engaging. the ECM tells the TCC to engage early when you have the selector in D and will not attempt to go above 3rd. so it sounds like its locking in 3rd, but when you attempt to get it in 4th, the ECM tells the TCC to unlock while it attempts to shift it... and it fails, so it stays in third and locks the TCC again... Â any codes? Quote Link to comment Share on other sites More sharing options...
augi Posted October 12, 2009 Author Report Share Posted October 12, 2009 that makes sense... but what would cause no 4th gear? i havent flushed the tranny yet because of yhis problem. the trans fluid is red... no signs of being burnt or anything like that. no there arent any codes Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 12, 2009 Report Share Posted October 12, 2009 could be a bad shift solenoid or some other internal problem. maybe even just a cut wire, i'm not sure. i'm looking through alldata but i'm not finding any info to see if the solenoids are NO or NC... that could rule out those if i had the info on them... Â did you ever ask the previous owner about it? Quote Link to comment Share on other sites More sharing options...
carkhz316 Posted October 12, 2009 Report Share Posted October 12, 2009 ^Depends on what gear you're in. Shift solenoids should be off for 2nd, but then 1-2 solenoid for 1st, 2-3 on for 3rd, and both on for OD, something like that. I'm a little foggy, its been awhile since I've had one apart. And usually I just replace stuff and fix whats broken in front of me, and not as much diagnosis. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 12, 2009 Report Share Posted October 12, 2009 with a 4t60e: Â SOL A SOL B TRANS GEAR ----- ----- ---------- 1 1 1 0 1 2 0 0 3 1 0 4 Â not sure how different a 65e is... Quote Link to comment Share on other sites More sharing options...
carkhz316 Posted October 12, 2009 Report Share Posted October 12, 2009 I'm pretty sure it's the same. Oops. I was wrong about default. It's 3rd instead of 2nd for Limp mode. Quote Link to comment Share on other sites More sharing options...
Dark Ride Posted October 13, 2009 Report Share Posted October 13, 2009 I have the same problem in my lumina except that it never attempts to shift to 4th, ever. I've just been driving it in 3rd, but I sure would like to figure it out. I was thinking that it might be solenoid A, but if it was I wouldn't have 1st gear right? Quote Link to comment Share on other sites More sharing options...
Crazy K Posted October 13, 2009 Report Share Posted October 13, 2009 I have the same problem in my lumina except that it never attempts to shift to 4th, ever. I've just been driving it in 3rd, but I sure would like to figure it out. I was thinking that it might be solenoid A, but if it was I wouldn't have 1st gear right? 95? no. There have been two answers  one member determined that his car would not go into overdrive because of the Neutral Safety Switch. The PCM did not get the right info from it to think the car was in O/D, apparently.  Another thing it could be is FAILSAFE MODE. The car will not engage the TCC or O/D if it thinks the tranny is overheating. Adding an auxiliary transmission cooler to the car has alleviated that problem. (first person to object gets cock punched) One trick to try: with the car at speed when the O/D should be working, turn the key off, and right back on. This resets the computer and may restore function as the PCM stays in FAILSAFE MODE until the next ignition cycle, even if the transmission has cooled back down. BTW, FAILSAFE MODE gives you 1st, 2nd, and 3rd gears only, with a normal shift pattern for those gears. Quote Link to comment Share on other sites More sharing options...
Dark Ride Posted October 13, 2009 Report Share Posted October 13, 2009 The lumina Does lock-up the TCC though, so I don't think it's in failsafe. I belive that the neutral safety switch was replaced with a known-good unit. Quote Link to comment Share on other sites More sharing options...
Crazy K Posted October 13, 2009 Report Share Posted October 13, 2009 "known good" doesn't mean good. I recommend removing it, opening it ans inspecting the innards, (easy to do) and then grease it up with dielectic grease. Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted October 13, 2009 Report Share Posted October 13, 2009 I thought failsafe mode only gave you 2nd and 3rd? Quote Link to comment Share on other sites More sharing options...
Crazy K Posted October 13, 2009 Report Share Posted October 13, 2009 I thought failsafe mode only gave you 2nd and 3rd? You are talking about LIMP FAILSAFE mode, which is when the PCM fails completely to command the transmission. If you were to unplug the tranny connector, you would be in LIMP FAILSAFE Mode. Not sure what else could cause it, though in theory a disagreement on an OBD II car between the tranny FDR and PCM FDR is supposed to. Quote Link to comment Share on other sites More sharing options...
Galaxie500XL Posted October 13, 2009 Report Share Posted October 13, 2009 Check the codes, see if it's giving a P740. If so, the TCC isn't engaging properly. The transmission will be inhibited to go into overdrive, you'll stay in 3rd gear. My '95 LQ1 Cutlass does this once the transmission temp goes above 179 degrees...time for a rebuild. Quote Link to comment Share on other sites More sharing options...
Crazy K Posted October 13, 2009 Report Share Posted October 13, 2009 Check the codes, see if it's giving a P740. If so, the TCC isn't engaging properly. The transmission will be inhibited to go into overdrive, you'll stay in 3rd gear. My '95 LQ1 Cutlass does this once the transmission temp goes above 179 degrees...time for a rebuild. does that light the check engine light? scanners are hard to find for obd 1.5... Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted October 13, 2009 Report Share Posted October 13, 2009 Check the codes, see if it's giving a P740. If so, the TCC isn't engaging properly. The transmission will be inhibited to go into overdrive, you'll stay in 3rd gear. My '95 LQ1 Cutlass does this once the transmission temp goes above 179 degrees...time for a rebuild. does that light the check engine light? scanners are hard to find for obd 1.5... Â scanners are kind of rare.... but if you have a laptop and an ALDL cable, i've got you covered for reading it... Quote Link to comment Share on other sites More sharing options...
Dark Ride Posted October 13, 2009 Report Share Posted October 13, 2009 "known good" doesn't mean good. I recommend removing it, opening it ans inspecting the innards, (easy to do) and then grease it up with dielectic grease. Is there anyway to actually test it? Quote Link to comment Share on other sites More sharing options...
Crazy K Posted October 13, 2009 Report Share Posted October 13, 2009 "known good" doesn't mean good. I recommend removing it, opening it ans inspecting the innards, (easy to do) and then grease it up with dielectic grease. Is there anyway to actually test it? yes, if you have the pinout info and a voltmeter. But several that had no issues were BORKED when inspected. Quote Link to comment Share on other sites More sharing options...
Galaxie500XL Posted October 13, 2009 Report Share Posted October 13, 2009 Check the codes, see if it's giving a P740. If so, the TCC isn't engaging properly. The transmission will be inhibited to go into overdrive, you'll stay in 3rd gear. My '95 LQ1 Cutlass does this once the transmission temp goes above 179 degrees...time for a rebuild. does that light the check engine light? scanners are hard to find for obd 1.5... Â I've got an Actron CP9110 that does OBD 1.5...unfortunately, I'm a little far away from you. However, when I first got my car, I cross-checked what the 9110 told me by getting a free scan at an Advance Auto Parts store...so some newer scanners do work at least in a limited way. A P0740 will not light the "check engine" light, though. Â Â Â Quote Link to comment Share on other sites More sharing options...
carkhz316 Posted October 13, 2009 Report Share Posted October 13, 2009 You are talking about LIMP FAILSAFE mode, which is when the PCM fails completely to command the transmission. If you were to unplug the tranny connector, you would be in LIMP FAILSAFE Mode. Not sure what else could cause it, though in theory a disagreement on an OBD II car between the tranny FDR and PCM FDR is supposed to. Bad ignition switch could; Just throwin it out there; since trans solenoids get B+ from the ignition switch. Quote Link to comment Share on other sites More sharing options...
DavidHowell3633 Posted October 15, 2009 Report Share Posted October 15, 2009 Crazy K mentioned that my car's OD issue was solved by proper adjustment of the NSS. For me, once I adjusted it so I could start it in neutral it would also shift into OD. So, again- for me, it was not a case of a bad NSS, it was a case of adjustment. OD hasn't failed to lock up yet and it's been about 4 months. Good luck in any case. Quote Link to comment Share on other sites More sharing options...
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