As we all know, one of the weak spot of the J is the transmission, w/ no external tranny oil cooler, the oil run thtough the radiator and back to the tanny, since the radiator don't do a very good job on cooling the oil and something the passage is simply clog in the radiator, causing the short life of a many J transmissions. To prevent that to happen, a regular flush and an external cooler is recommended by many. Since my car has a little over 100k miles, i do have the usual jerk when the car shift from 1st to 2nd gear, after i drain and refill it like 3 times(w/ ~1k miles of driving in between) it usually goes away after a few miles of driving, when the tranny oil warm up. But after ~$65 and an hour of work putting the cooler in, the jerking feeling seem to be getting worse I think the cooler is just doing too good of a job, it keep the fuild from warming up. Of course the jerking is getting smaller with more distance, but i can still feel it in a longer period of time compare to no cooler. What can i say, at least i know the cooler is working and the tranny is going to last longer. A trade off, i guess. Droping the pan and replacing the filter would be next. Anyway here are a few pics

Its very possible the trans isnt heating up as fast as it used to...

One of the Q guys had the same thing and they replaced the temp sensor and it worked really nicely.

zerothread/173956

Interesting, soldering a resistor inline to fool the TCU. After looking into the FSM, the pin(#33) they use for the temp sensor is the same on the J and the Q, i'll go do a resistance test with the sensor in the car. Again, Thanks

I used the two pin(33 & 35) on the TCU harness to test the resistance og the fluid temp sensor, and the resitance came to 0.6 k ohm (it was taken in the morning, have not driven the car for a least 10hrs) , according to the FSM the valve should be 2.5k ohm - 0.3k ohm, from cold to hot, with the 0.6k ohm from the test, i'm pretty sure that i need a new temp sensor, but for now, i am going to put in a inline resistor like the Q45 guy, and hope it would fix it. Now the question is, i went to radioshacks trying to get a 1.5k ohm resistor, but there are 1/4 watt, 1/2 watt, and 1 watt resistor to choose from. I ask the guy that work there and he said it is important to know what watt do i need and said if i put iin a wrong watt resistor, i will blow something up, either the sensor, TCU or something else. Now can anyone tell me which one should i get, the 1/4 watt, 1/2 watt, or the 1watt resistor? Help, please.

NismoChi,

From what I remember from Electronics course.

You need to measure the voltage on the resistor and then calculate now much wattage it has on it with a formula: W = U^2/R where ^2 is the power of 2. U voltage on the resistor and R the Ohms. Then just multiply it by factor of 10 just to be on the safe side and then take a standard value close to the calculated. Like 1/8, 1/4, 1/2, 1, 2 watts. This should be the value for you. Hope this will help

NismoChi wrote:I used the two pin(33 & 35) on the TCU harness to test the resistance og the fluid temp sensor, and the resitance came to 0.6 k ohm (it was taken in the morning, have not driven the car for a least 10hrs) , according to the FSM the valve should be 2.5k ohm - 0.3k ohm, from cold to hot, with the 0.6k ohm from the test, i'm pretty sure that i need a new temp sensor, but for now, i am going to put in a inline resistor like the Q45 guy, and hope it would fix it. Now the question is, i went to radioshacks trying to get a 1.5k ohm resistor, but there are 1/4 watt, 1/2 watt, and 1 watt resistor to choose from. I ask the guy that work there and he said it is important to know what watt do i need and said if i put iin a wrong watt resistor, i will blow something up, either the sensor, TCU or something else. Now can anyone tell me which one should i get, the 1/4 watt, 1/2 watt, or the 1watt resistor? Help, please.

hey, chek this out.. its adjusting your tps.

http://forums.f31club.com/phpB...t=413

The normal voltage range is 0.5 volts to 1.5 volts.

driftkaztik wrote:hey, chek this out.. its adjusting your tps.

http://forums.f31club.com/phpB...t=413

Hey you know what the funny thing about your post is, i am not sure if you were asking me to try adjusting my TPS to fix the 1-2 gear shifting problem. Or you meant they are adjusting "MY" TPS in that pic. As a matter of fact, they were, that is a pic i took on my car when i was rebuilding my 88 Z31 Turbo, I post that pic a while ago to show a member (on this Forum, i think) where the TPS is located.Any, I went out again this morning to do the resistance test using a ohm meter, the resuld is telling me the Fluid temp sensor is in fact bad, so i am going to buy a 15k ohm resistor to trick the TCU. Still not sure which one to get, 1/4, 1/2, or 1 watt, can someone do the math for me, please. i am not good at that.

Heres my math.

1.5^2/600 (.6k ohms = 600ohms) = .00375 x 10= .0375 =~.04

1/8 would be the closest.

Nismo measure the voltage between the 2 pins that you did (with ignition ON) and let me know the voltage.

Thanks man, i'll do that but it''ll likely be tomorrow, cause the battery in my muti-meter went dead, i need to get a new one first. But the resistor value is 0.4k ohm after been sitting all night.

nismochi... sorry didnt know, someone posted it on the m30 club and it has worked for many.

sorry for showing you your own picture!! ahha

I installed one in my J30, but not because I had any problems. Yeah, I heard the q's trannys go out because it over heats. Honestly, I don't see a difference since the J motor and tranny isn't as big as the q.

Is there any way to put a kind of thermostat or thermal valve inline. So the ATF only flows through the cooler when hot??

daltonnnn wrote:I installed one in my J30, but not because I had any problems. Yeah, I heard the q's trannys go out because it over heats. Honestly, I don't see a difference since the J motor and tranny isn't as big as the q.

You wont notice a difference..... but it is doing good!

shortlid wrote:Is there any way to put a kind of thermostat or thermal valve inline. So the ATF only flows through the cooler when hot??

you cant do that because otherwise it would starve the trans for fluid.