well i recently have been encountering a bit of a problem. for some reason my trans tends to shift hard from 2nd to 3rd. This usually happens when i drive it on a cold start in the morning, but after about 20 mins of driving it doesnt do it anymore.

When it slips, it will be driving normally until 3K rpm in 2nd, then when it goes to shift to 3rd, the rpms lag and then jump to 3500rpms and then finally shift into 3rd. it also feels quite rough when this happens. Once again, this only happens when i first start the car in the morning and dies down in roughness after about 20 minutes.

Forgot to add, i am no longer boosting. The only mods i have now are a CAI, Header, and full exhaust. I also have the Hayden trans cooler still on. The slipping began about 2 weeks after i stopped boosting i believe.

 

Could be damage. But before you think that, when's the last time you drained the trans fluid?

Also are you using the correct fluid from Toyota? I suggest two drain and fills (since this is the poor mans way of getting rid of the fluid without using a machine to vacuum it out, which is bad for the trans). For 2007+ I believe it's WS fluid, check your dipstick.

Another thought is to unplug the battery, let it sit for 20 minutes or more, then reconnect the battery, and see if the slipping still occurs. The auto trans on the tC can learn and does learn driver behavior, unplugging the battery causes it to lose its memory and revert to standard settings.

another idea i just had was the cooler. If the cooler for the trans was over-cooling the trans, the fluid wouldn't warm up to its operating fluid temps, and that could cause harsh shifting as well which would take a longer amount of time to warm up, hence the 20 mins later it shifts fine.

 

HHmm ive found it reboost sloved

 

I'm having similar symptoms on my '05. Started happening right after we had a cold front, and now it's gone away as it's warmed up. At 100K I dropped the pan and put in a new trans filter, along with new ATF. Now that it's no longer dipping into the 40's at night I haven't had any issues with morning cold start slipping.

 

yes, it did actually start slipping when it was cold, and it gets worse as it gets colder.

 

sorry to "tread jack" but my issue is similar and did not want to create a new tread...and I dont know if I am just noticing something that is normal but feels "weird" to me and I never paid attention to it...

Background on the car:
I live in PA, so for the past 2 or 3 months it been cold, snow, and freezing temps

2005 Scion TC. Auto. Used. 100,000 / 10 yrs warrantee.

Currently 80,335 Trans Flush at around 65K

Mods –
DC header, 2.5 Spipe, custom exhaust all 2.5" (Magnaflow high cat, 22”magnaflow resonator high flow, and SRS exhaust), Injen CAI. Other mods but not related to engine such as suspension, body, interior...

Ok about a month or 2 ago, the car was acting funny; basically the car idles high. When I would give it gas, it would act as if the MAF was defected, it would bug out and stall, did it to me 3 times. If I let it sit, the idle would drop to like 300rpm and it would act like it wants to stall, then the RPM would shoot up to like 1000rpm and go back and forth.

I had it towed to the dealership the same day this happen…they check it no codes, no “issue” diagnosis maybe bad gas. 2 other friends said the same thing. Before this, the car had no issue. So I let it sit in my driveway for about 5 hrs running burning gas. Next day I re-filled my gas and everything seems fine.

About a month ago or so I had a throttle body clean. When I got the car back from the dealer that day, the car idle was at 1000-1200. It was weird, I drove off the dealership, got to a red light and out of no where the RPM shot up to about 1500 and the car jumped forward (scary). So I drove about ¼ mile, and it kept doing it, when at a complete stop the RPM would just shot up to about 1200 or 1500 and stay there. When driving and placed the car into neutral, the car rpm would fluctuate between 500 to 1200 and it would just isolate back and forth back and forth.

Immediately I returned to the dealership, I was informed that maybe the throttle body was stuck open so they were going to recheck it. Tech checked it and said that he reset the ECU, sometimes after cleaning the throttle body, the system don’t register that the throttle was clean so the ECU needs to be reset. Car seem fine after that.

Didn’t really see the RPM shoot up.

Recently with all the snow and really cold days, for example, all last week (Feb 12-19) no lie, the car temp gauge did not go past the first line right after the letter C. My digital Temp gauge read a temp of 115-130 MAX! preaty sure that colder temps makes the car idle high. For a whole week, the car did not heat up.

The idle RPM was closer to 900, car fells as if its accelerating even though its in P, or as if its in D but i'm holding the brake and accelerating at the same time. Then I noticed that when I drive, depending on the speed the car feels as if you dropped it from D to 2.

This is what is happening now: If I accelerate to 50 continuously, then I let go of the gas, when the car reaches 40mph the car honestly feels as it drops into N. The exhaust sounds quieter, and the RPMs drop off, if at 42mph the RPM were at 1400 the RPM at soon as you reach 40mph they drop to 900 then shoot back up to 1200, that quick drop again feels as if the car shifted into Neutral, then shifted back to gear.

If you are doing 30 or 40 or 50 and you press the break to decelerate to 0, at 5pmh mark the car feels as if you shifted from D to 2. There is a kick as if something is pulling you back, you hear the RPM shot up and then drop off again.

Yesterday, Friday February 25, 2011 the car heat up to 190 but not higher. Normal temp for the car is about 198-212, most time around 202. The shifting issue was still there, but the car idle at around 700.

Since I got my Scan gauge about 6 or 7 months ago, I noticed that normal idle both at P or at D or at N is between 640-740 normally is 668 (digital reading).

Ultimately, I don’t know if my transmission is going bad, if my exhaust is causing some type of back pressure to cause this (doubt it), feels as if 3rd gear to 2nd is stuck and 2nd to 1 is stuck too.


Am I crazy? Thanks Guys!

 

If you mean that its seems not to be shifting when its cold its supposed to do that. It tends to hold the car in 2nd gear for a while untill the engine temp gets up to operating temp.

 

do you think it is normal for the car not to reach operating temperature and remain at the first line of the temp gauge for a whole week? any other day the car reaches the middle between C and H in the temp.

So its normal for the car to hold 2nd...then drop into neutral (feel like goes into N) then go back into gear? and feel that change in RPM from 1400 to 900 back to 1200 at around 40mph? how come it only happens at around 40pmh and 5mph?

Thanks for all your help and anyone else that can provide some feedback

 

Sorry I didnt look at the dates on the post I was answering the other post.

But to answer your question no that doesnt sound normal at all. idk where to even start at I want to say its gotta be something in the trans. if the trans was going bad the trans would slip alot. I dont think you have a engine problem.

 

Thanks. Update>

went to AC NJ, was bored and hungry went to the Borgata buffet! geat food. 50 mile trip, the digital temp gauge did not go past 140 degrees. The needle did not go past the middle between the First line and 2nd line. Idle heavy at 1000rpm. Both ways, cruise control 65 mph RPM steady at 2399rpm.

when I got home. Temp at 150. Let it sit in my driveway for a while and it reached 180. Idle seem to be more around 670rpm (almost normal). The "up and down shift" of rmp at 40 and 5mph still occurs.

 

sounds normal to me, esp if everyone is saying this is happening during cold days. Basically the tranny temp is supposed to reach a certain point before it can shift into 3rd, you can check the dealer on this one.

 

Thanks, maybe is just crazyness on part. My first car died exacly at 100,000 weird as hell...my car now (TC) is paid for, 80k on it and still hae 5 yrs 100,000. so plenty of time left...just want to make sure if something is wrong, i can get it looked at and replaced under warantee...my crazyness also comes about because Team Toyota in PA, kept telling me that there was nothing wrong with my caliper but the front right was frozen...as soon as I hit 36K and my regular warantee expired, they admitted that I needed a new caliper and refuse to do it under warantee...So far Falkner Toyota in PA has treated me like a king...they check any issue I have for free and have always treated me wih respect...

Thank you all for your help and ideas...

 

Update...feels like its getting worst - car at dealership being checked out...should have a diagnosis by tomorrow...will post on Weds...Wish me luck...if anything hope warantee covers it...

 

I will be looking forward to your update today.

Anyway, i live in chicago and its been extremely cold here too. When it was below 20 degrees, my car acted very strange also. not to thhat extent but it didnt run good at all. im not boosting my automatic tc anymore (put the kit in my manual tc so its all back to stock. I had a VERY rough idle, and i was told to clean the MAF. and that made a hella difference.

also, yea the trans will stay in 3rd gear when its cold. and it may shift a bit rough. mine shifted really rough because i also had a trans cooler, so it took forever to even get the fluid to a liquid state from a peanutbutter mixture lol. but yea, i wanna hear what the problem is from the dealership, thats crazy. sounds like you got your hands full!

 

Ok got the car back:

Diagnosis: Thermostat had a hole through the ruber seal, causing the car to run to "cold" since the car could not regulate and increse temp to reach temp needed for optimal performance. Basically it was open 24/7

Due to this, the car was running at a higher RPM since the car is basicallly "cold" all the time.

Since the Thermostat was replace the car iddles at 640 and has reach temp of 190 (still a bit cold here)

so far so good.

Tech stated what most of you said here regarding RPM and gears. He stated that at 4th gear is all motor and the shift between 4th and 3rd seems "rough" because the car is running so cold, the car didnt want to go into 4th in the first place. He said I felt the shifts and drop in RPMs more because the car was running at a higher RPM and was ideling higher due to thermostat issues.

Since the replacement one, car shifts smoothly. SInce the car idles at a lower RPM, you dont feel the drop and increase in RPMs as before (previoulsy stated above)...its a lot more smooth now...

Any questions let me know.

Tech explained to me the gear ratios, and at what speeds you reach each gear...

Good luck to all and thanks for the info...

 

i get similar issues with my 05, especially in the morning when i dont "warm" up the car i would drive and it would stall and i can see the rpms shot up its scary and the car feels like its going to expode hahah idk at least im not the only one ;) with the issue

 

Good Luck Sako...

 

np my philly buddy, side note i work in philly lol what part of philly are you from

 

I work by Route 1 / City Line Ave at the Department of Veteran Affairs! GOV WORKER

I live in south Philly, by Tony Lukes. 2nd and Oregon

Your in the area you can treat me out to eat...all homo...

Question:
After changing the thermostat I started reading articles regarding engine temperatures. My car was running "cold" because the thermostat remained open, circulating coolant.

I saw that TRD and other companies sell Thermostat that raise or lower the operating temperature...Understandable to lower temp for track purposes and so on, the car did feel a bit more powerful at a lower operating temperature since RPMs were always high...

but why would someone buy a thermostat that would raise the operating temp of the car? what performance gains can you get from a car that is running hot? or
are those made for people that live in way colder areas?

Thanks for entrataining my stupid questions...

Thanks