dmcclymo

[QUOTE=pogoism9;4121296]spiking needle can also be caused by air in the cooling system. Did you guys bleed it and properly refill the cooling system after install?[/Q


Yes. We have gone over the cooling system a few times.

jgscott

iTrader: (1)

I'm telling you. I had the exact same problem. When we check the coolant temp w/ a guage when it read peak hot, it was not hot at all ! I bled that system about 5 times and even had a pressure pump bleed. Did not reslove the problem. It will run fine until the temp gauge goes haywire. It's a ground wire. If your guy will drop the Tranny at no charge, you may see it then. Or it could be a ground else where, but like Steve said, look for a ground off the engine, that grounds to the engine. As soon as the ground was fixed my car ran perfect.

stevechumo

iTrader: (5)

Try this without removing the tranny to find the ground. You can do this at home. Make a ground wire with 14 gauge or bigger. Bigger is better & size does matter. The smaller gauge number means the wire is bigger. Make sure you use the wire terminal connectors on both ends so the inside tiny wires won't get loose.

Unbolt the last bolt from the tranny housing that mates to the engine. That bolt is 12mm. You don't need to remove the bigger 17mm bolt on the top. Connect the wire through that bolt and wrench that bolt back to the tranny housing tightly. Connect the other wire's end to the engine block or to the battery's negative. Disconnect the battery for 1/2 hr. and reconnect it back. Warm up the car for at least 5 minutes & drive it around a few blocks. Shut down the engine, turn it back on, drive again and see what happens. Good luck.

dmcclymo

Hey guys, I've been looking for this ground with no success. My mechanic said that he will have to drop the tranny as you said to find it. I really do not want to do that since I will have to pay additional labor because I took the car from the mechanic that did the swap because he had it for 3 weeks trying to figure out this problem.

Currently we cannot see any grounds on the tranny. The only grounds we see coming from the harness are bolted to the left and the right side of the head to the back of the engine. Space back there is really tight.

Jgscott, if possible please try to see if the shop that did your fix have more percise info on where exactly in the engine this wire comes from. Any help will be greatly appreciated. Thanks.

stevechumo

iTrader: (5)

You're lucky. I took this photo when I took off my SC400 tranny. I believe that's the ground wire mentioned. That's the only ground connected to the tranny.

jgscott

iTrader: (1)

Ok let me try to clear this up some.

1. I don't remember the wire being a Ground to the Tranny, it was a ground from a engine wire, to the engine, not tranny or the frame. It was behind the tranny on the back of the engine.

2. I'll try to see what shop notes they still have for you, when they resloved it on my car. Now you may have a different problem but..... you sure are going thru and having the same exact issuse I had. Another option might be to take it to Lexus, let them know what I said, and see if you can't get them to fix it for only a 1 hr labor charge ( $ 120 - 150 ?? ) .

3. If you can get someone to look at a detailed shop Book, look at the back of the engine wiring, engine wiring harness from the engine, and wiring from the ECU connector back to the engine. Look for a wire that connects into or screw grounds and " Grounds TO The Engine itself .

jgscott

iTrader: (1)

We must have been typing at the same time. Soon as I posted there was your pic LOL !

He needs a pic or Diagram of the wiring harness from the engine, and from the ECU. I know its the same but he needs to look from both ends for a wire that either plug connects, or screw grounds to the Engine itself behind the engine tranny match up. Not a Tranny Ground. From what I was told to pull the engine with the wire harness you don't even need to disconnect it. But some how people always do not realizing. .

jgscott

iTrader: (1)

Good Help Steve. Needs Bare pic with tranny out of way.

dmcclymo

Thanks for all your help guys. Between the info I got from you and Steve I am confident this thing will work itself out. I think tomorrow I will bring it to Lexus and hope they can take care of it in one hour like jgscott suggested. I will give them the info you guys gave so they will know what to look for. Thanks again and I will let you know how it goes.

jgscott

iTrader: (1)

Hey I talked with my Dealer that fixed my car today. Without going back and pulling the hand written notes they said it was a engine to engine " Back Ground Strap ". If you don't get it, ask someone to try to see if that is listed on the engine in the book. If not I'll ask him to pull the paperwork, but he could not until Mon because they were backed up with shop work.