RB20 doesnt idle when warm, HELP!

[munkeijoe]

Hey guys, I have a 1990 240sx with a 1993 cefiro RB20 in it. did the whole swap from start till now, and theres this last problem that is occuring with the engine that is really frustrating.

When I start the car, I have to give it just a little gas, but once it starts, it will sit and idle. now, here is the weird part. when it gets up to operating temp or just starts to get warm, it starts to bog down and eventually, if I dont give it any gas manually, it will idle up and down, and then will die.

I checked the ECU codes and found out the Water temp sensor and Throttle position sensor are coming up as faulty. I ordered a new water temp sensor and that should be here next week.

Now, how can I check that the TPS is actually bad? when I adjusted idle it worked find for the small black plug youre supposed to unplug for the IAC adjust, but im guessing it involves the big gray plug for the ECU code situation?

And while I brought up the IAC, I remembered. When I turn my car off, I have to unplug the IAC at night cause it stays on. key out of ignition and everything, you can sit there and plug it in and unplug it, and you can hear the internal spring open and close. I took it off and made sure that the click noise I heard when I plugged it in was actually the spring opening up and it is.

What could be causing these problems? and How do I check if the TPS is bad? like what are the specific voltages its supposed to send, etc.

Also, on the water temp sensor, is it just a ground and a signal wire? or a power and ground? power and signal? Cause I took a power probe and just put it up to it and got a ground on one and nothing on the other?

Any help would be greatly appreciated. Also if you live in the northern California/Sacramento area and think you could come personally help, I will gladly pay you. I just desperately need this car running.

Like I said, any help would be appreciated. Thanks!

-Joe

[xxsptcuztomsxx]

All of the questions you have can be answered by spending some quallity time with the FSM. I belive the sensor testing questions would be in the troubleshooting section.