ATT: US SC4 owners!!!

[6spdSC4]

I'm still having problems with the car. It shuts off when you mess with something electronic. It doesn't do it all the time but it has been doing it more and more reciently. I have asked before and been told it is more than likely a ground wire somewhere but I have not begun to check it. Does anyone know what else it could be? I need to get this crap fixed!

 

[Lextreme II]

Sounds like something and somewhere has a loose wire....... That is the hardest things.. none reproducable.

 

[Lextek]

Can you be more specific on the problems when you mess with something electronic?

 

[6spdSC4]

Alright so here's the deal: This is beginning to happen more and more frequently. When I start the car it starts and idles fine. I can basically tell that the car is going to act up when I go to shift into reverse. As soon as I press on the brake to shift I will see the dash lights dim a little bit. From there it gets worse. If I'm driving down the road and make any kind of sudden braking the lights will dim hard. If I have the radio on loud or windows down or something like that and brake hard and fast the lights,radio, ac will all cut out for a second or two. When it is at it's worst the car will actually shut off and refire by itself. One time the car actually died as I was driving down the road and never refired. I had to slap it in neutral and restart it. Also, this is the very weird part: If I see that it's going to do it I can sometimes shut the car off and restart it and it will run fine. This doesn't happen all the time but I've noticed that it does work sometimes.

SIDENOTE: Anyone know where you charge your AC on a US spec? I know you normally charge on the High pressure but I was reading my buddy's Chilton for his little Honda Civic and it says in huge bold letters to charge on the low. I tried to recharge mine a few months ago on the high but the pieces we had from the kit didn't fit on the high pressure valve just like we did on my buddy's civic before we read the maual. Any thoughts?

 

[Lextek]

OK, Im not there to see the car but here goes! Remove your battery and the tray under the battery. You will see where the ground cable bolts to the body on the side of the frame. Remove the bolt and inspect for rust or corrosion on the cable "eye" that the bolt goes through. If there is corrosion take a wire brush and clean it off. Clean the bolt also.And the frame area that it bolts to. Do the same on the engine block where the ground cable terminates. If the cable has a considerable amount of green corrosion or the cable looks bad enough, replace it. This is fairly common on the SC and it shows up in ways like you described. Leaky batteries are the most common cause. You may notice a lot of white stuff under that battery tray. Smile if you see this and think how simple it was to fix, and prevent. Always flush the battery tray and battery with water when cleaning the engine.

A/C... ALWAYS charge from the LOW side only. There is a reason you could not fit the charge hose on the high fitting. If you are using a small can of freon, it can burst if connected directly to the high side. Be careful!!! The low side is on the compressor manifold. There is another by the passenger side firewall for checking the health of your Evaporator Pressure Regulator.

If you need a ground cable, let me know. I can get the OEM stuff cheaper than you can and shipping it does not cost that much!

 

[6spdSC4]

You are the man! Too bad I'm working right now, otherwise I'd be outside in the garage fixing it instead of typing this! On stock SC's there is a pressure cap sticking out of the rad. cover, I don't remember if this is the high or the low, do you know off hand? I tried putting the hose on that one and it didn't fit, I'm kind of excited to think that I was just a dumbass and putting it on the wrong one. $14 bucks later and nice cold A/C in Florida would make me a VERY VERY happy man! How many cans should it take? I was thinking two since it's not fully empty.

 

[Lextreme II]

Lexteh,

That is where experience comes in. Lexteh have 16 years of experience with Lexus and was a Master Diagnostic Tech for the Dealer. He knows what he is talking about. When r u coming to LA California. I need your help. Got a short somewhere too.

 

[Lextek]

The high side is the one sticking out of the plastic shield in front of the radiator as you said. Just a note! If you are adding freon, it has leaked somewhere. You have not said what year SC this is, so Im not sure if you are on R-12 or R134a?

Dont get too excited because the freon you install may come out as fast as you put it in. We can troubleshoot that later. Lets get the electricals in working order first, then work on other issues. The A/C could get quite a bit more technical...

 

[Lextek]

Lextreme,

I dont get to L.A. very often. What short do you have?

 

[6spdSC4]

It's a 1995 and I guess it's been converted to R134a. I was a little sad to hear you say I have a leak somewhere. I was kinda hoping that my car was just older and it ran out!

 

[Lextek]

You may have a leak somewhere. If the A/C is not cooling, we have an issue of some kind. If it cools a little, we are probably dealing with a low freon issue. The '95 was 134a from the factory.It should hold about 2lbs, there is a yellow sticker under the hood that will give the spec. Charge to the max weight.

It will lose some over time and that's normal. If it is just low and you dont have to continue to install freon, that's great! Your SC's weakest link in the A/C is the evaporator. You will need a full system and a refrigerant leak detector to do it right! If you don't have the tools then I suggest taking it somewhere and have that part diagnosed. The tools are too expensive to use once or twice!