auto trans stays at 2100rpm at 100 but not always...??

[jas98]

hi, sometimes but not always my auto seems to want to cruise at 2100 rpm at 100 and not engage the torque converter as when it does it goes down to 1800-1900rpm (which i think is about right?) now it only really does this if i give it half to 3/4 throttle when i go from 20ish to 100, and holds its at round 2100rpm for a while then sometimes but not always it will engage after a fair few k's and go back to normal rpm

what going on? trans still shifts gears fine, changed throttle postion sensor 3 times to see if it was that, leads and plugs are new etc...im guessing some valve in trans? no error codes, or maybe its common with the tourq converter? also trans fluid fine and full and changed it and filter a few weeks ago and still does it (been doing it for ages ) i got a MACE memcal but it was doing it before that was installed so it wont have anything to do with that

any one else had this problem?

cheers

[BlackVXGTS]

Sounds like you are having problems intermittent problems with your TCC (Torque Converter Clutch) lockup. Check out item 13 of 4L60E common problems. From your description, your trans hasn't reached the stage where you get no lockup, just a delayed lockup.

13. No TCC lockup: Brake pedal switches improperly adjusted (always on), TCC solenoid failed (easy fix in the pan), TCC clutch worn out (must remove trans and replace TC).

[Brett_jjj]

The auto trans will set an error code 67 (TCC clutch solenoid circuit fault) if the ECU commands the TCC to lock up and it doesnt do so for whatever reason, and seeing theres no codes being set,the problem is not likely to be in the transmission itself, otherwise a code would be setting. It might not be getting commanded to lock up in the first place when its supposed to... It could be a memcal or an ECU problem. Id check all the wiring and connectors etc, and if theres still no difference, then try another standard memcal or another complete ECU if the standard memcal makes no difference to the problem.

[hako]

Try disconnecting your battery for 30 seconds - this can sometimes clear glitches from the ECU that cause very strange problems. Try it and hopefully you'll be surprised.

[monkeys437]

This happens to mine but only when the car is completely cold. My street pulls out to a 100km zone and on a warm morning it takes about 500m for the revs to drop about 200RPM and the converter locks up. On a really cold morning it takes about 1.5ks for the same to happen. Its been doing it for years and never got worse so I'm not fussed by it but I'd be interested to know what causes it so I might look at getting it fixed if the problem gets worse.

[sircruisealotVS]

This happens to mine but only when the car is completely cold. My street pulls out to a 100km zone and on a warm morning it takes about 500m for the revs to drop about 200RPM and the converter locks up. On a really cold morning it takes about 1.5ks for the same to happen. Its been doing it for years and never got worse so I'm not fussed by it but I'd be interested to know what causes it so I might look at getting it fixed if the problem gets worse.

That's not a problem, it's just how the transmission works. It won't lock up the converter untill it's reached a set temperature within the transmission. Similarly to how you might notice on cold starts the auto trans will hold gears longer for a little bit.

[monkeys437]

That's not a problem, it's just how the transmission works. It won't lock up the converter untill it's reached a set temperature within the transmission. Similarly to how you might notice on cold starts the auto trans will hold gears longer for a little bit.

Ok good to hear. Thanks for clearing that up!

[hako]

The OP's problem sounds a bit different: now it only really does this if i give it half to 3/4 throttle when i go from 20ish to 100, and holds its at round 2100rpm for a while then sometimes but not always it will engage after a fair few k's and go back to normal rpm
This is an intermittent problem - if it was related to the trans oil temp it would not fluctuate as once it was warm enough it would stay that way. I'd still try the battery disconnect.

[jas98]

ok thanks guys, some really helpfull info ther, i will try disconnection battery and cleaning electrical connectors etc, i dont think its the memcal as it did it with the stock one as well as the MACE one (which makes car go goo lol) however could well be teh ECU

i might change the auto oil again in near future and change the torque converter solenoid for good measures

its got a fairly large auto oil cooler on it and a corvette servo so all other gears etc change correctly (cars done a little over 160 000 k's) does it when hot and cold

i was told a while ago that it could be a valve in teh trans thats aparantly common with these types of autos to not lock up the converter somtimes and to fix it you install a corvette servo, but im not too belivable as the auto place was trying to sell me a shift kit etc


thanks all

[sircruisealotVS]

The OP's problem sounds a bit different: now it only really does this if i give it half to 3/4 throttle when i go from 20ish to 100, and holds its at round 2100rpm for a while then sometimes but not always it will engage after a fair few k's and go back to normal rpm
This is an intermittent problem - if it was related to the trans oil temp it would not fluctuate as once it was warm enough it would stay that way. I'd still try the battery disconnect.

Yup, i was only commenting on monkeys post (which is why i quoted his post to avoid confusion), which is definately temp related, not the OP's.
That being said i wouldn't completely rule out temp being an issue with Jas98's problem - but not with the trans being too cold. When the trans is too hot it will delay converter lock up too. Auto transmission, particularly electronically controlled ones are a strange beast.

[jas98]

yeh im thinking temp related to, i no the correct way and best way is to fix whats broken, however ive herd some good things about some additives,maybe give it a go? and see how it turns out? some say they fix torque converter lock up problems although this would be a marketing technique saying it will do one thing but do absolutely nothing in the end, ive used i think it was "lucus" branded stuff before, thick stuff but it did stop some leaks and helped me trans in me old vn i had

also mabe its the solinoid playing up or sticking? and is this the one for these trans? 2004R 700R4 700 4L60E 4L65E NEW LOCK-UP SOLENOID KIT | eBay

thanks

[jas98]

ok update, if i put the trans in 3rd then switch it back to 4th (D) it locks up straight away, only really doesnt lock up converter if i put foot down, but locks straight away if i quickly switch to 3rd then D.....any ideas?

[hako]

Can you re-phrase that update....I'm probably dumb but I don't really get the hang of it......my initial response is that it will never lockup unless you are at a steady (more or less ) speed for a few seconds.

[jas98]

sorry was typing fast

basically while cruiseing at 100 (driving in D) touqe converter doesnt always lock but if i move the selector to 3 then back to D, when it goes back into D after doing this the converter is locked straight away otherwise if i dont do this it stays at 2100rpm for like ages or untill i stop then go again, could it be a sticking valve in teh gear box? im gonna head down to trans place and ask em however they will probly say it needs recoing when its probly something simple

[scott-95]

power/eco button?...

[hako]

I suppose it could really be caused by the throttle position sensor as well, or the speed sensor or one of a dozen things...I think if it was a sticky solenoid it would throw a code but I'm only guessing. Does it do it when CC is on?