Engine Problems!

[brandon green]

Ok...I bought this car for $580.00. A 1992 Lexus SC400 with 160,000 miles. Here are the problems...a leaking water pump. Then it overheats. No indications of blown gasket (milky or foamy oil). Once it overheated, it started idling crazy rough. It idles smooth when cold, then it goes rough once warm. Now, the battery is dying after one day of sitting. I just tried to jump it like usual (even though it has a new battery, it dies within a few days) and with the batteries attatched, it won't start. Well it won't hold an idle. It just dies. HELP!

[1992LexusOwner]

About the water pump leaking, you will have to tear nearly all the front of the engine off to get to the water pump. While you are in there I would replace the thermostat, timing belt, timing belt tensioner, 2 pullies, idle tensensioner, drive belt, caps, rotors, wires and plugs, change the oil, seafoam it, to help maybe with the idling issue a little, and replace with new air filter. Make sure you put fresh antifreeze in there too. You will not have to pull the radiator. Also inspect the upper and lower radiator hoses for cracks and wear.

The overheating maybe from the water pump not pumping 100% through the block. Could be a faulty thermostat?

The rough idling could be a vaccuum leak, leaking injector (s), dirty throttle body, crank position sensor bad, theres 2, TSP going bad or not adjusted right. Start at these few simple things.

Battery issue could be the alternator is going bad, not keeping the battery charged while running. Most of the common problems with the alternator going bad is from a leaking power steering pump or resevoir, its directly over the alternator. Keep a close eye on it. Known to cause problems with the SC. If you need the links for the timing belt replacement and for the power steering replacement, let me know, and good luck!

[Tomj8]

Ok...I bought this car for $580.00. A 1992 Lexus SC400 with 160,000 miles. Here are the problems...a leaking water pump. Then it overheats. No indications of blown gasket (milky or foamy oil). Once it overheated, it started idling crazy rough. It idles smooth when cold, then it goes rough once warm. Now, the battery is dying after one day of sitting. I just tried to jump it like usual (even though it has a new battery, it dies within a few days) and with the batteries attatched, it won't start. Well it won't hold an idle. It just dies. HELP!

You may have multiple gremlins at work, since there is no apparent connection between the idling problem as you describe it and the battery issues. The difference in engine idle between cold start and warm engine may point to the fuel injection control module which is designed to automatically adjust the fuel rich for engine start and cold running, then automatically readjust to a leaner mixture when the engine reaches normal operating temperatures. The mixture differences between cold running and normal operating temperature can be detected in exhaust emissions, and since emissions are monitored by the ECU it can't be completely ruled out as a potential bad actor either. As for the battery, be absolutely certain the new battery isn't defective! It's rare, but it happens. If it's OK, there is a significant short circuit somewhere in the system that is draining the battery. Try charging the battery to full and leaving the positive cable disconnected over night, then hook up the positive cable next day and see if the battery starts it. If it does, the automobile wiring or an electrical component has a significant short. Have you checked the alternator to see if it is charging as it should? Even shorted diodes in the alternator can drain your battery!

[LEX_MAN]

If i was you i would pull the engine and rebuild everything.I know it sounds crazy,but since you got so many problems its not worth fixing one thing and guessing about everything else.

Pull the engine,take off the alternator and get it tested.

Then clean the radiator,install new waterpump,and while you there check the head gasket,timing belt,plugs,valves etc...

I have a blown head (sc300) but my oil was fine.The car overheated few times.I tore it appart and discovered white crap under my valve covers.

[eatingupblacktop]

You can start emptying your pockets into what sounds like a money pit and hope you get the car up to spec before you run out of cash. Or you eat the $580 you spent and get a better car that's worth the investment of your time and money. As Lexman says, it's going to be one thing after another. So, if you've got plenty of cash and nothing better to do with your time, you'll certainly become familiar with the car. In the end, I'm not sure that the total cost won't be higher than if you just bought a car in better condition.

[LEX_MAN]

You know what? 160,000 miles is not a lot of miles for the 400,i still think theres plenty of hope....just check the body for rust,if theres minimal,just try to spend less money on parts,dont get the parts from stealership...Exept the head gasket,thats important.

If you do all the work your self it will be a lot cheaper,kinda like 70% off :D

[brandon green]

That sounds very promising. The previous entry discouraged me into wanting to get rid of it. The body is in great shape. No rust. It drove decent for awhile. Just that constant drip and battery problem. Once I cleaned the engine compartment out, the altenator acted a little bit better. But I was a little confused as to what the drip actually was. It being red and all...I thought it was transmission fluid. I realized it was coolant after I changed the transmission fluid and oil change and ran outa choices in fluid color. I realized it was outa coolant when it overheated. Every since then, the idle has been terrible. And now when it starts...as soon as it gets warm the idle is so low it dies out. So I'm hoping that it needs new plugs, a water pump, and all the accessories that goes along with that change. I can start there I guess. I want to do it myself...but I'm still trying to figure out where the plugs are on this thing. Anymore opinions I would love. Thanks in advance.

You know what? 160,000 miles is not a lot of miles for the 400,i still think theres plenty of hope....just check the body for rust,if theres minimal,just try to spend less money on parts,dont get the parts from stealership...Exept the head gasket,thats important.

If you do all the work your self it will be a lot cheaper,kinda like 70% off :D

[UCF3]

Anti-freeze is also red in colour. have you checked your level lately.

It almost sounds like the biggest problem is the cooling system. have you swapped the water-pump and swapped the fluids yet.

The battery could just be bad also. Try this, swap it with one of Jags, and see if you're able to run with it for a day or two.

[1992LexusOwner]

Let me help more about the fixing the water pump and changing all the things I mentioned in the first reply, including changing the plugs. Go to www.lexls.com... Look on this website for every step of the way for everything you need to do basically with hand tools on this car. But keep in mind, its for a LS400, not a SC400, but the motor and transmission is the same. Find the timing belt replacement and print off all the pages. Maybe 30 pages... It gives step by step instructions... even the torques for all the screws. Make sure you read the directions... Also make sure you have plenty of room to work, lots of stuff to be taking off. Take your time... You can do it !!!! Save you hundreds of dollars. The only thing different is the removal of the radiator... You DO NOT have to pull the radiator.... The last thing is, if you get to the crank pulley and cant get it off with an impact, slide a socket over the head of the bolt with the longest ratchet you have, preferrably a 1/2 inch or larger, and slide on a cheater bar over the ratchet. Wedge the cheater under the frame of the car somewhere, and bump the starter. DO NOT crank the car. Just BUMP IT !!! It will make your life alot better.. Its like cutting butter, and its old school method. That crank pulley has 182 foot pounds of torque... Thats alot. Also remember to make sure the ratchet is in the loose mode and NOT the tight mode, after you slide the pry bar over the ratchet. Good Luck and let me know how it goes if you decide, if you need help.... you know where to find me...

[1992LexusOwner]

I found the link for you... www.lexls.com/tutorials/engine/timingbelt.html

[brandon green]

Thank you so much for your help. People like you make this website what it is. I will be taking on the challenge soon. I just drove the Lexus up the street and around the corner and it died at the enter section. The battery went bloop!.....the alternator is shot. My wife brought my other car up to me and I attempted to jump the lexus. But when I let off the gas...it died over and over again. Tow truck?....we'll see soon. I'll give it another shot in about and hour. Also....there's a light odorless smoke the emits from around the engine....kinda out of the black plastic attatchments on the front and side of the engine. So much stuff to fix....it seems.

I found the link for you... www.lexls.com/tutorials/engine/timingbelt.html