4howard

My check engine light came on a few days ago, went to oreilly and got it scanned, P0420 came up, catalytic converter inefficient Bank One something like that.

I looked up some other threads but it appears this code is very ambiguous. I know one thing for sure is, my LS400 is a bit louder than it should be which leads me to think its a leak/bad gasket. I'm also getting HORRIBLE mileage, ie 200 miles per tank. Could it also be an oxygen sensor?

Guess I'm going to have to take it to the dealer but would like to know what to expect so I don't get ripped off so thanks for any replies in advance.

My check engine light went on at about 90k miles on my 95 LS400, and its been on ever since. It was diagnosed at times as an oxygen sensor and at other times as the catalytic converters. Over the next 60k miles I have replaced the oxygen sensors and a leaky exhaust pipe and mufflers, but not the converters. Car runs good and sounds good, and gets good gas mileage, about 350 miles to the tank, combined city highway.

One thing for sure, the dealer consistently ripped me off, my local mechanic has been reasonable and reliable. Good luck.

The LS400. Great car, lower mileage. Simple choice.

I have a similar problem. My driver window goes down randomly when I unlock the door with the key. It will sometimes go down when I unlock and open the door from the inside. There does not seem to be a definite set of conditions that cause the window to just go ahead and roll itself down. I asked for help on this some time ago and no one had any suggestions except that I should use the remote to unlock the door. My remote does not work. So now at least I know that since you have a similar problem using the remote, the remote is not the problem.

There are some interesting threads on the Corvetteforum regarding sludge in the radiator. It seems that when certain types of antifreeze are mixed together they can form sludge. One of the the posts also goes on to describe a case where the antifreeze was mixing with the engine oil and creating more sludge.

Now I am not a mechanic, but it would seem to me that something just got into your newly cleaned oil pan to create all that sludge. Ruling out the local neighborhood vandals, that would leave only gasoline, rainwater, or coolant, that could possibly gain access to the inside of your engine. My feeling is to always try the lowest cost shots first. Flush the radiator, replace with the proper coolant, Lexus specifies its particular type of coolant, make sure you bleed all the air out of the system and pressurize it, and then see if you get the sludge again. Also, take a look at what comes out of the radiator. MY 95 LS has 150k miles on it, and the engine runs smooth as silk, no reason yours should not either.

Good Luck.

Remotes can be found on eBay. Prolly cheaper than an ECU.

Don't they need to be programmed or something? Or does the sender need to be matched with the receiver under the hood?

Now what?

Use the remote. Ditch the keys.

That stopped working about 10k miles ago. :cries:

1995 Lexus LS400: When I turn the key in the driver door lock and unlock the door, the window rolls down about three seconds later. Has anyone out there had this problem, and if so, do you know the fix?

Seems to me that it might be a "feature". Are you by chance, turning the key twice (or more)? Some models were programmable to do special tricks when you turned the key several times.

Jim, 1990LS400 is an expert on dredging up model features. Maybe he will chime in.

Nope not it.

Anybody out there have a clue?

I believe what we are collectively trying to say is that the ECU is being fooled into thinking you are holding the key (when you really are not). It is probably a switch issue (sticking or bouncing contacts) or chafed wire in the door. I think you will have to remove the panel to do some further investigation. You may try cleaning or replacing the door switch.

I think it is not a switch issue. I opened the lock on the passenger side door, which when turned unlocks all four doors, and the driver's side window rolled down. Now what?

Anybody out there have a clue?

I believe what we are collectively trying to say is that the ECU is being fooled into thinking you are holding the key (when you really are not). It is probably a switch issue (sticking or bouncing contacts) or chafed wire in the door. I think you will have to remove the panel to do some further investigation. You may try cleaning or replacing the door switch.

Sounds like a plan. Was hoping not to have to take off the door panel. Thanks.

1995 Lexus LS400: When I turn the key in the driver door lock and unlock the door, the window rolls down about three seconds later. Has anyone out there had this problem, and if so, do you know the fix?

Seems to me that it might be a "feature". Are you by chance, turning the key twice (or more)? Some models were programmable to do special tricks when you turned the key several times.

Jim, 1990LS400 is an expert on dredging up model features. Maybe he will chime in.

Thanks for the response, I am familiar with the window roll down feature. In fact this car was purchased new by my Dad in 1995, and I remember thinking how cool it was to be able to roll down the window with the key. But this is rolling down after one turn to the right and release. Today it rolled down at some point I cannot identify, I came back to the car and found the window open.

As a test I turned the key once to unlock the door, quickly opened the door with my other hand, and then quickly locked the door with the door open. The window did not roll down.

Anybody out there have a clue?

1995 Lexus LS400: When I turn the key in the driver door lock and unlock the door, the window rolls down about three seconds later. Has anyone out there had this problem, and if so, do you know the fix?

why are you reposting the same question? This has been discussed thoroughly in your prior thread.

http://us.lexusownersclub.com/forums/index.php?showtopic=67323

Maybe because she has not found a mechanic who agrees with the advice she got on the forum. Maybe she's waiting to see if anyone actually did change the water pump. The problem with this repair is finding a mechanic willing to fix the heat without selling any parts or hours of labor.

I have had this problem in my 95 LS400 and finally seem to have it solved. First you need to be sure that the correct coolant is in the system. Then you must be sure all air is bled from the system. The mechanic who finally got this right put the car on the lift with the front tilted up, so that the air would be forced forward. Then the system was checked for air leaks, one troublesome point is the connection to the overflow tank. With the system properly filled and pressurized, I now have heat. It took one expensive and futile trip to the Lexus dealer, and two trips to the local service station who finally took the time to work this out with me, to get it right. You should know this is a common problem, it comes up on the forum all the time.

Good luck.

I have found two causes of problems with my heat in my 95 LS400. One cause is the use of the wrong type of engine coolant. Lexus specifies a particular type of coolant which is different than other cars. The other cause I've had is that the system needs to be pressurized and all air bled from the system. One mechanic solved this by putting the car on a lift and lowering the rear of the car to force the air up and out. He called it burping the system.

As for the mileage, I can tell you that my 95 with 145,000 miles still gets about 18 city and 25 on the road.

hi everyone im new here...i recently bought an ls 400 ,that was working remarkably well for four month..but last night ,for no apparent reason the engine management light turned on,no weird noise and it just came out of the garage where i had a complete check of all fluids and leaks.. before i take it to the dealer i would like to know what kind of problem i could be facing here...steve 2006 help!!! thank you!

I have a 1995 LS400 with 144,000 miles. My check engine light has been lit for the past 55,000 miles. After a lot of money at the dealer, the light was out for about 50 miles and then came back on. I had my local guy check the car out and he said he suspected an oxygen sensor. We changed three but the fourth would not come out, it was too rusted in.

At any rate, the car runs great, I've replaced the y-pipe (or is it an x-pipe), cat, tuned up, etc. But I live with the light.

Greetings Gents and Ladies,

Started out on a 600 mile trip and found cold air blowing with the heater on.

Was going to cancel the trip, didn't want to get sick, drove 40 miles stopped

in a lube shop asked to use a hammer, tapped the area of the thermostat

heat worked okay for the trip.

Got to where I was going, purchased and put in a new 185 degree thermostat

and the heat worked okay.

Took a drive tonight, Saturday, and...NO HEAT...blowing cold again.

Gotta' return Monday...needless to say I'm baffled.

Anybody got any ideas?

PLEASE SAVE ME FROM A COLD RETURN TRIP!

Had the no heat problem in my 95 LS400. Make sure you have the coolant filled to the proper level. You will need to be sure there is no air in the system, on my car this required the car to be put on a lift with the front raised higher than the rear to force the air up and out of the radiator. Finally, make sure all the seals are tight - especially the one on the plastic overflow tank. If the gasket on the overflow cap is broken or cracked or missing, you could be getting air in the system. Good luck.

welcome to the club. i have never been able to resolve this. spent $2k at the dealer, worked for a bit, then zip. Had the coolant changed, system bled, burped, dont even remember what else. still cold except when traveling at consistent highway speeds. wish i had the answer...

I have had a similar problem for about four years on my 1995 LS400. When idling, or stop and go traffic, i get cold air. When I increase to highway speed, the air will gradually warm up and supply satisfactory heat.

After a $2000 trip to the Lexus dealer, the problem was solved for a few weeks. They claimed "my local service station" filled the cooling system with the wrong type of coolant. When I returned with the same problem two weeks later, they told me there was air in the system and that it had to be "burped". The dealer described a procedure where they raised the front of the car in order to force the air out of the system. Winter ended, the problem returned the next season.

Each fall I bring the car to my local service station to bleed and burp the system as described by the Lexus dealer. The fix usually lasts a few weeks. I have never heard what the problem is caused by. :(

sorry about that blank.

I have a 95 with 130k and the car is good. I would recommend you fix the leaks and keep driving. My engine light has been on for the last 40k miles, I have been told to change the catalytic converters but that would cost $2000, or so they told me. The car passes emissions inspections so I just keep driving.

hey everyone. i'm new to the forums obviously. my '90 LS400 is starting to get a little older so i decided its time to join up and starting tackling problems before they get bigger.

i purchased the car in 2005 for $2,500 from a friend who was leaving the country. it had around 90k miles on it. yes i know it was as great deal! i've loved it ever since.

i've recently decided that its time to do a little work on the car to prevent major repairs. i have about $400 leftover in my budget for this month (it was a cheap month) and decided that I'd like to put it toward the car to try and prevent a $2,000 repair in the near future. it current has 130k miles on it. i haven't done too much work to it in the 4 years i've had it. the only major problem i've experienced in the past 4 years is replacing the alternator. it burned out when the plugs to the battery were lose and the alternator could not send the electricity back to the battery (or so i was told).

here is a list of the current problems i have and how i deal with them.

1. Radiator fluid leak. I was told awhile ago that I had a small leak and every so often I'll have my radiator light comes on. I usually just wait for it to come on and then I pour in more of my 'Toyota Red.'

2. Power steering fluid leak. Every so often I start to hear a suspicious noise when I first turn on my car and start turning my wheel as I'm driving. I just add some power steering fluid and it goes away for a couple months.

3. Antenna won't go up. I hear it trying to go up/down every time I turn my car on/off.

4. RPM gauge in dashboard doesn't work. The indicator just stays flat. I think maybe this is as simple as replacing a fuse?

5. Front windows struggle going up and down. I've had problems with this in the past. I'm not sure if whether there is anything stuck down there such as pine needles from a tree I used to park under, or if the electrical system is having issues.

6. Check engine light came on for about 10 mins about 2 months ago. Don't know if something is on its way out, or if it was simply a small, brief malfunction.

I can live with these issues, as I have been for a couple years. But I'd rather fix them if they are going to lead to bigger problems. I haven't done any 'real' maintenance to my car for a good amount of time. No real differential fluid flush. No transmission fluid flush. Etc etc. Basically I turn down any offers for additional services when I go to Jiffy Lube to get my full synthetic oil change, except my air filter when its looking dirty.

Honestly, I don't want to perform any unnecessary maintenance...but I want to take care of my car. I'd say I find mechanics fairly untrustworthy, but I know that I'm going to have to let them do what they need to do eventually. Before telling me to do something myself, take into consideration that I have no garage and I have no tools. However, I am willing to purchase (cheaper) tools and learn how to fix something if it will save me cash in the end.

My question is...where do I go from here? Do you recommend me going to get some sort of an inspection to figure out what problems I have and their severity? Is there some maintenance/fluid flushes/etc you would recommend I do immediately? What would be the best use of my $400? Is there anything you recommend I do myself?

Thank you very much for reading the post, and thanks even more for any advice. I really appreciate it.

Pete

When I stop my 95 LS400 at a light the air temperature from the heater begins to fall and becomes completely cold. At cruising speed the heat is fine. Coolant level is full and air has been bled. Help it's cold in there!