Coolant Loss And Rough Idleing

[killerFatty]

Yeaterday I sea-foamed my car and pulled all the spark plugs an sprayed a little seafoam into the cylinders. Last night on my way home I turned on my heater and got cold air. I was shocked, but since it was raining I didn't look at anything when I got home. Today when I checked on her, she was out of coolant. Nothing in the resivour. So I filled it up and a few hours later I checked the leval again and took it for a spin and let it warm up. It never stopped heating up and got very near the red mark on the temp gauge before I got back home. I checked the coolant and there was none left. Also on the cold start it was idleing kind of rough. I heard a few missfires and it was vibrateing quite a bit. After I drove it a little this behavior quite and the idle returned to normal. I haven't done any real diagnosis yet because it has been raining, but I have always had a slight small tiny coolant leak. Like I would lose about a half inch in the resivour evey 2 months. Nothing like this. Also when I open the hood and rev it the coolant comes in bubbles back into the resivour. It has done that since I can remember and I never thought anything of it untill now. I hope it's not a head gasket... which I think it might be. Any advice would be very helpful. I plan on checking the oil and seaing if it looks like chocolate milkshake and maybe doing a compression test of all cylinders as well as trying to locate the coolant leak. I am thinking of haveing a shop do a pressure test on the coolant system to find the leak, but what do you guys think I should do???

[landar]

Yeaterday I sea-foamed my car and pulled all the spark plugs an sprayed a little seafoam into the cylinders.

Please do elaborate on the Seafoam into the cylinders. How did you do that? And why?

[Brett in AK]

If you're lucky it will only be a blown headgasket. Since this has been going on for quite awhile it may have turned into something more serious. Hopefully it will not be a cracked block or head. What was the purpose of pulling the spark plugs and "seafoaming" the cylinders? Hope it works out for you, but I'd be prepared to get the checkbook out and start practicing writing BIG numbers! :(

[maxed_out]

Anybody know how bad a job replacing the head gaskets are? I dont need one, and hope I never do but I'm curious????

[killerFatty]

Anybody know how bad a job replacing the head gaskets are? I dont need one, and hope I never do but I'm curious????

13.7 Hours plus $70 for each gasket. That includes cleaning carbon and making all neccessary adjustments.

I simply pulled out the spark plugs and cleaned them off. Then before replaceing them I squirted a tiny bit of seafoam into the cylinders. I have sea foamed my car before and only got positive results. It drove fine before so I don't see how it could have had any previous damage to the head gasket. Thats why I am not sure what happened.

[killerFatty]

UPDATE. I just checked my car and after a cold start this morning it ran fine right off the bat. I pulled it into my driveway and checked the oil and it looked fine. NO MILKSHAKE. YYAAA!! But the coolant was leaking from the lower front of the engine about where the water pump is. Also there was a rattling noise from the inside of the engine. It was coming from the front half and it didn't sound like a knocking rod so I am thinking it might be the water pump making a noise. Any ideas. BTW I am at 95K miles on this T/B and Water pump. Should I just replace the TB and water pump?... if I can find the money.

[lexfourcam]

good to hear that its not the head gasket,but i would highly reccommend to get a new timing belt and water pump asap. you dont want to burn her up. probably should change the pulleys because one of them could have a bad bearing.

[curiousB]

You might want to do a cylinder leak down test too be sure. I had a ford V6 blow a head gasket a few years back, symptoms were lost coolant and some misfiring. If compression won't hold then indicates problems with gasket or valves. This sounds more water pump related but it might give you peace of mind doing this test.

[killerFatty]

do you mean just compression pressure test the cylinders?

[eatingupblacktop]

Sorry to hear about your troubles Killer, especially so soon after your bangup. If the car's idling/running smoothly now, then unbalalnced compression isn't your prob. Did your low coolant level warning light come on? How is the temp now? In addition to all the suggestions you've received so far, you could pull any DTC's you might have. Could check your coolant temp sensor. Also check your overflow tank to see if any coolant has escaped through there. Any smells? Noisy w/p or noisy idler means a t/b service in your future. You really should nail the location of the leak and noise before starting to replace anything. Throwing parts at a prob without determining the issue is like pi$$ing in the wind - you never hit anything because the wind takes it away! :P Do you know whether the last service used oem? Keep an eye out for any smoke which would indicate a shreading t/b.

[VBdenny]

If a headgasket had blown you would be seeing a lot of white smoke from the exhaust. I kind of doubt that is the problem and be glad if it isn't. In addition to problems mentioned by others is the fact that when a head gasket fails, anti-freeze/coolant often leaks into the motor oil. Coolant is highly corrosive and if it mixes with your oil, your engine is done. Maybe not right way but the damage to the bearing has been done and it just takes awhile for problems to manifest themselves. After watching several videos of people Seafoaming their engines on youtube, it seems most people really rev the engine hard while in Park which isn't that good for them. I would never even consider using Seafoam after watching that.

Get a engine stethescope and do a little listening just be carefull not to get caught on a belt or anything. Spend some time and figure out where you can safely place the sensor.

[curiousB]

do you mean just compression pressure test the cylinders?

They're similar. Leakdown test is just with the engine not running and crankshaft in a position that for the cylinder under test the valves are fully closed. Then you pump up pressure of cylinder through an adapter hose assembly. The key is to see how fast the pressure drops once you pump it up. That is an indication of leaking rings, valves, or head gasket...

[killerFatty]

I just took it to my local shop. It continued to loose coolant along the way, but it didn't over heat because it was only about 2 miles away. It ran nice and strong the whole from start up untill I turned it off. They are taking a look at the water pump and that is my main suspect too. There isnt any excessive exhaust smoke. No codes or lights either. No coolent warning light which made me upset when I found out there was no coolent left in the block, radiator, or resivour. What triggers that light to come on anyway?

[91LS400Lexus]

No coolent warning light which made me upset when I found out there was no coolent left in the block, radiator, or resivour. What triggers that light to come on anyway?

Does that light come on when you turn on the ignition? If so, the bulb is good and it may be a faulty sensor. My 1991 LS400 was the opposite... the light (low coolant) always stayed on (99.9% of the time), yet the coolant was full. It was a bad sensor - I am suprised the light hadnt burned out already. Since I had the temp gauge, I never worried about it. It was like this even before I bought it.

Sorry to hear about your misfortune. Hopefully its not the headgaskets... this is pretty rare on an LS400. I had a clanking start up from the water pump area... turned out to be the fan bracket bearing. If you do have a new water pump installed, I would recommend replacing the fan bracket as well if its never been changed. Mine went out at 221K. They may last longer though... my old 1990 LS400 had almost 280K (had 215K when I got it) and it never needed one AFAIK. Its just when they do need it, you have to take it down almost to the water pump/t-belt to replace. Mine was $60 parts and I knew a Toyota mechanic... charged $125 labor.

[killerFatty]

Problem is fixed!! To the tune of a new TB and water pump. I got the tensioners replaced too as well as the distributer caps and rotors. The noise and leak was coming from the water pump and the coolant inlet housing had a leak too. It feels great to have it fixed and no longer have to worry when my TB was going to go. It had 97K miles on it so it was a bit over due.

[91LS400Lexus]

Does that light come on when you turn on the ignition? If so, the bulb is good and it may be a faulty sensor. My 1991 LS400 was the opposite... the light (low coolant) always stayed on (99.9% of the time), yet the coolant was full. It was a bad sensor - I am suprised the light hadnt burned out already. Since I had the temp gauge, I never worried about it. It was like this even before I bought it.

Did they change the fan bracket bearing I mentioned above, or had it been replaced before? I had a clanking start up from the water pump area... turned out to be the fan bracket bearing. When one does have a new water pump installed, I recommend replacing the fan bracket as well if its never been changed. Mine went out at 221K. They may last longer though... my old 1990 LS400 had almost 280K (had 215K when I got it) and it never needed one AFAIK. Its just when they do need it, you have to take it down almost to the water pump/t-belt to replace. Mine was $60 parts and I knew a Toyota mechanic... charged $125 labor.