Transmission slipping? or....
 

Over the past few days I noticed a weird problem. Sometimes when I stop at the light for instance sometimes just slow down the car acts like its in neutral, sometimes I have to go to N then D a couple of times to start going again.

This happens sometimes and sometimes it runs normally. When I give it gas it will rev up then go all at once.

anybody know what this could be? is my transmission bad? at first I thought I needed a fuel flush but I dont think it would rev up like that.

Ideas?

- Kal

solenoids may be on the way out perhaps?

isnt that something to do with the starter? this problem occurs only when m on first gear. and it happens more often when over drive is on.

do you always have it on overdrive? and the solenoids i believe is what sends the signal to switch gears, correct me if im wrong...

It used to be on OD all the time, I switch it off until I hit the highway. still does it but not as much. As for the solenoids I dont know exactly how they function thats just what i heard my pops mention one time.

I went to the transmission shop they told me i gotta come back and spend around a buck to run a diagnoses. Asked him what he thinks from experience told me hard to tell.. I think he just wants me to pay him. did this happen to anybody before?

have you checked the fluid level on the dipstick? low fluid can do that.
solenoids are on the transmission themself and are responsible for shifting the gears when they get the right signal from the ecu. don't hear about these going out as much as the trans itself, torque converter going bad is another possibility.
check the fluid first. if not youre gonna have to make the shop test it and if you get it rebuilt make sure you get a warranty. you could also replace with a used one if the trans is the problem but thats more of a DIY than a shop thing.

I checked the dipstick this afternoon the fluid seemed to be there, I will recheck tomorrow as well, if i dont reply back tomorrow its due to exams all day.

Is that guy price for the engine checkup is right? I will be checking other shops too whenever I get a chance but how does a buck sound reasonable?

I double checked fluid this afternoon, theres enough fluid, dark as hell though imma have to change it tomorrow or monday.

Today while driving with 2 stock wheels (back) I encountered another strange thing, while backing up the car just switched off as if I was driving the stick and didnt give enough gas. Happened again while at the light (with all stock wheels on) when I stopped, switched to N then back to D because light turned green.

I noticed that when im stopped and I shift to 2 and start driving I face no problems, goes, shifts to second gear then I shift to D and drive normally. Also this problem happens more often while OD is on. I am starting to believe its something to do with either 1)gas reach to the engine or 2)torque converter (as sometimes theres a lot of torque and some other times low torque)

Does that help diagnose the problem?

Yeah, swap a manual!

Just kidding, I had this problem with my 1jz swap. I did swap a R154 in, but came up with the info needed to get the auto working.

Speed sensor 1 (3 wire) comes from the trans, and goes to the dash ->

Dash sends out Speed2 (2 wire) that the ECU uses for reference to shift.->

ECU then uses Trans selector switch to reference what gear the car is in. ->

Based on that info, the ECU then adds power to the solenoids in a specific order.->

S1= ON S2= OFF = 1st Gear
S1= OFF S2= ON = 2nd Gear
S1= ON S2= ON = 3rd Gear
S1= OFF S2= OFF = O/D

This is the loop that the ECU uses to control the Trans.

I would get under the car, and check out the Trans harness, make sure there are no shorted wires, etc.

The solenoids don't usually go bad, but the solder on them does, so the Pan has to come out to fix if so.

Thanks for the info dude, my dash isnt all that and my speedometer is bust... only works after driving the car for a while, sometimes decides not to do that either. The RPM needle yesterday didnt move when I started the car, but then worked normally. Dash got to go. but it cant possibly be the reason can it?

I will get those checked out and post my results.

On a side note I AM saving up for manual swap forget all that auto crap ;)

Usually, whenever a car acts like it's in neutral at idle when you're revving (and you can feel it engage in drive when you go from N to D) then your clutch pack is done.

Hmmmm that makes sense too. How do I check the clutch pack? how do I replace it and where do I get it from? I checked online with no luck.

I'd suspect a transmission rebuild would be in order in that case. Either that or find a good condition second hand unit out of a wreck or here on the forum.

Could you please elaborate? Do I have to change the whole transmission or take it apart and change some parts and put it back together?

http://www.gottransmissions.com/blog...on-clutch-pack

You would have to take it all apart. I wouldn't even bother if it's gotten to that point.

You might end up better off taking it to a transmission shop (reputable) and spending $70 on a diagnostic to know for sure, it may not be anything serious but more than likely it is.