Ls400 1995 - Trac Off + Engine Light Blinking, Loss Of Power, Car Shak

[arnaudfabs]

Hello,

First i would like to say that i am not a mechanic and that English is not my first language, so please bear with me :)

4 month ago it all started. I went to get gas at a random gas station and my LS 400 started to act out. Trac off light is constantly blinking. Engine light was already on when I bought it 2 years ago and it was certainly a glitch. Now, it happens that it blinks, sometimes when the car really runs bad. and sometimes it just stays on.

So, when it acts out, here are what happens:

1. I have very low power when i push the gas pedal
2. There is a click sound sometimes the first minutes I drive the car coming from the engine
3. The gears jump so does the whole car
4. The car shakes when i am at a red light on D, less on neutral but still shakes a lot.
5. I am starting to get some gas smell inside the car.
6. While driving, i feel like the engine is struggling so much at times like it needs air if it was a human being.

I read on this forum that it might be the spark plugs, the wires, maybe the gas filter but i a not sure at all.

I really need to know what is happening and if someone can help me with some more information with the info i shared. I wish not to go to a repair shop not prepared. i love this car :) A surgeon sold it to me 2 years ago and it had been well maintained and it is a very clean car.

Thank you a lot!

[steveuk]

Sounds like your only firing on 4 cylinders, if so this will do your cats no good.

Common failure is the drivers side ignition coil opposite the battery tray.

Would be a good idea to have the engine codes read first as this will point you in the right direction.

[arnaudfabs]

Steveuk:

Thank you for your reply. Firing means that it could be the spark plugs?

Thanks

[Exhaustgases]

http://www.lexls.com/tutorials/intro/codereading.html

You need to do this read the code thing first and tell us what it says. There is also a connection port on the engine driver side up front of the intake plenum, in front of the egr stuff.

You can use a bent paper clip to connect the proper terminals. You don't need a fat wire like in the picture.

[arnaudfabs]

Here is what the repair shop wanted to fix for $3,480

http://img4.imagetitan.com/img.php?image=12_3c42d6b5-d832-480a-ba5c-98c67eb4e92d.jpg

[Exhaustgases]

Since it is likely a 95 you have, maybe its an OBD2 you need a code reader or go to an Oreilly's or Auto zone and they can check it for you for free.

This is the first step to trying to fix it.

But since it is running so bad, I would look at things like the coils and distributors first. It could be as simple as a goofed up rotor or a coil that came unplugged. Maybe rent or buy the code reader, when using it the engine is not suppose to be running.

[arnaudfabs]

i went to autozone 2 months ago and they told me i had 30 codes showing up, i asked to have them they would not print them for me - it had 4 cylinders issues. I went to the repair shop 5 days ago, they did not give me the codes but the parts that need replacement (see attached picture in previous reply). Since then i have decided to teach myself mechanic and will buy an OBD2 reader.

I have changed my air filter this morning and also removed the MAF sensor and cleaned it with MAF sensor cleaner, car shakes less but still really struggles with power. Also, when the car was running, i removed the MAF sensor electrical plug and it shut down the car which means (according to videos i watched) that the MAF sensor is working and the repair shop wanted to charge me $500 to replace it... i will teach myself and do everything myself.

[Exhaustgases]

On some electrical items it is not a good idea to disconnect stuff when there is power applied. Like when taking out ecu's and removing things from the dash like radio and climate control, you always want to disconnect the battery.

I'm not sure about your year car, but on the older generations you can not clean the Air meter unit, any cleaning will ruin it.

You need to check the items I mentioned above. Also you could do this test as well. He does the test near the end.

https://www.youtube.com/watch?v=VG3EZJlyjl8

The test will show if the coils are connected and working and if the ignitors are good. If both ignitors and coils pass then check distributors and caps. Also cam position sensor will be suspect.

When was the timing belt done? The ecu could be an issue too, also engine mechanical. Its a process of elimination.

And you mentioned maybe bad gas, could be that or water in it, you really need to rule out the gas thing too.

Is that gas still in it ?

[arnaudfabs]

It started with bad gas i think 3 months ago. Since then car never ran good again.

I do not know about the timing belt, i will have to check on the repair records the previous owner left me. They always serviced the car very well since 1995.

I will watch the video and come back to the forum tomorrow and do the test in between if i am able to :)

the car is fairly low mileage (144,500) for a 1995 car i think?I got it 2 years ago with 134,000

Thanks for your help Bob!

[Exhaustgases]

I don't know the 95's as well as the older ones, but another thing to just change because they do seem to go bad and cause a bunch of problems. Is the Engine coolant temperature sensor, they don't cost a lot and you can change it while checking the distributors. And of course don't just do it yet till the igniter test hopefully that fails on one and you find the problem. To change the temp sensor you have to deal with the spark plug wires as its under and on the passenger side.

[sha4000]

Yes plz get a code reader. The 95 is OBD2. Once you have the codes post them up here and we'll try to figure out what's really going on

[arnaudfabs]

Ok, sorry i was on another lexus forum... I found the problem. I accessed the ECU and removed it. Opened it and saw the notorious capacitors leaks. Cleaned the acid on the board and put back the ECU in the car. it's been 5 days now. Car runs so smoothly i just can't believe it!

See thread there: http://www.clublexus.com/forums/ls-1st-and-2nd-gen-1990-2000/807090-ls400-1995-shaking-loss-power-smoke.html#post9308622

And very usefull info about the capacitor here: (luckily i did not have to replace them "for now")

http://www.clublexus.com/forums/ls-1st-and-2nd-gen-1990-2000/656360-all-my-crazy-lexus-issues-solved-ecu-leaking-capacitor.html